Our latest publications

• Tondeur, Jo; Howard, Sarah K.; Bucchiarone, Antonio; Scherer, Ronny & Braak, Johan van (2026). How we study what we study: A methodological review of 50 years of educational technology research. Computers & Education. ISSN 0360-1315. doi: 10.1016/j.compedu.2026.105760. Full text in Research Archive Show summary

  Research in educational technology has been extensively mapped in terms of what has been studied, but far less attention has been paid to how it has been studied. This paper reports a methodological review of fifty years of research in Computers & Education, covering a corpus of 5,516 articles published between 1976 and 2026, with the principal findings based on the post-1996 full-text corpus. Using an AI-assisted analysis, applied to full texts and abstracts, we traced the evolution of research paradigms, approaches, and methods across the journal's full publication history. The principal findings are based on the post-1996 full-text corpus. Pre-1996, full-text machine-readable files were not available for analysis. Analysis of pre-1996 abstracts was possible and are included to provide context for trends observed post-1996. The findings show that quantitative approaches and questionnaire-based data collection have constituted the field's sustained methodological centre of gravity. Within this dominant pattern, two shifts stand out: 1) the rise of systematic reviews as a recognised approach, and 2) a computational turn. The range of methods used in research has grown steadily, suggesting a gradual broadening of the field's repertoire. These patterns are only visible across multiple decades. Findings reveal that quantitative dominance is not a recent development but a persistent structural feature, and that the computational surge is better understood as a second wave following a peak in the mid-2000s. These findings have implications for what kinds of knowledge educational technology research is equipped to produce. The study argues that understanding a field's methodological history is a prerequisite for extending it.

• Sixtus, Elena; Lonnemann, Jan; Yan, Song; Li, Peng & Göbel, Silke Melanie (2026). Language-dependency of the left-digit effect in number line estimation and the role of number word inversion. Scientific Reports. 16(1). doi: 10.1038/s41598-026-54579-w. Full text in Research Archive Show summary

  Abstract Language plays a critical role in shaping cognitive processes. The present study focuses on the impact of language-dependent number representations, specifically examining the effects of number word inversion and the left-digit effect across different linguistic groups. Number word inversion is a phenomenon where in certain languages, such as in German, spoken two-digit numbers start with the unit preceding the decade (e.g., for 91, literally “one-and-ninety” rather than the Arabic numeral order “ninety-one”). Previous studies employing various numerical tasks indicate that the inversion effect—where the unit digit exerts a disproportionate impact on how the total magnitude of a two-digit number is perceived—influences children’s performance. This study addresses the inversion effect in adults by comparing German-speakers to English- and Mandarin-speakers in a number line estimation task. Linear regression slope analyses of estimated positions conducted across decades identified the inversion effect, demonstrating that German-speakers provided comparatively higher estimates for numbers with larger unit digits compared to the other language groups. Additionally, the left-digit effect, which conversely is characterised by the smaller impact of the unit digit on perceived number magnitudes, became evident in all three language groups. This left-digit effect is further modulated by membership of a specific language group. The structure of Mandarin number words is discussed as a significant factor contributing to the pronounced amplification of the effect. Our findings suggest that language plays a pivotal role in persistently shaping the cognitive processing of numbers.

• Schwitzgebel, David; Falck, Andreas; Decroix, Jérémy; Strickland, Brent; Papeo, Liuba & Wittenberg, Eva (2026). Encapsulation of the visual perception of social events from semantic priming. Journal of Experimental Psychology: Human Perception and Performance. ISSN 0096-1523. 52(8), p. 1000–1013. doi: 10.1037/xhp0001438. Full text in Research Archive Show summary

  Social event cognition draws on both higher level semantic processes and lower level mechanisms in visual perception. However, the interaction between these levels has not yet been precisely characterized. The present article investigates whether the visual perception of social events is encapsulated from the direct, top-down influence of semantic information. To test this, we leverage a phenomenon reflecting the visual perception of social relations: the two-body inversion effect. Across a series of experiments conducted on French-speaking participants (N = 373), we identified a novel semantic priming effect: Verbs (as opposed to nouns) selectively enhance responses to socially relevant stimuli. However, the two-body inversion effect itself was not influenced by this priming effect, suggesting that the visual perception of social events is encapsulated from higher level semantic processes.

• Carson, Alexis Christine; Zidan, Mahmoud; Olstad, Emilie Willoch; Gervin, Kristina; Galesloot, Tessel E. & Scholte, Iris [Show all 9 contributors for this article] (2026). Genetically Informed Research Designs in Perinatal Pharmacoepidemiology: A Methodological Overview. Drug Safety. ISSN 0114-5916. 49(7), p. 761–773. doi: 10.1007/s40264-026-01647-9. Full text in Research Archive Show summary

  Despite the widespread use of medications during pregnancy, ethical and methodological barriers to clinical trials make observational studies necessary for evaluating medication safety in this population. Observational studies are prone to biases that often limit their validity due to the lack of randomization; integrating genetic information through discordant sibling designs, polygenic scores, and Mendelian randomization can address several confounding issues. However, application of these three approaches in perinatal pharmacoepidemiology has been limited. Complementing traditional designs with these genetically informed research designs can tackle common biases and strengthen causal inference. This paper focuses on applying genetically informed research designs to child outcomes in perinatal pharmacoepidemiology by reviewing various methods, discussing their strengths and limitations, and examining their application to date, as well as considerations for implementing them in future research. Such considerations include the availability of genetic data, the complexity of integrating genetic data with existing epidemiological data, and selection of appropriate genetic instruments for analyses. Incorporating causal inference in perinatal pharmacoepidemiology can ultimately contribute to enhancing safe medication use during pregnancy.

• Ystrom, Eivind (2026). Editorial: When children also shape the family environment. JCPP Advances. 6(2). doi: 10.1002/jcv2.70136. Full text in Research Archive Show summary

  Family research in child and adolescent mental health has often been framed as if influence runs mainly from adults to children. Bjørndal et al. provide a timely corrective. Using longitudinal network models that separate within‐person from between‐person associations, they show that adolescent mental health difficulties and family dynamics are interrelated over time, and that emotional symptoms may precede later hyperactivity/inattention and sibling problems. Their findings also point to reinforcing loops within the family system, particularly between low family support and negative feelings towards the family. This matters because family members are not merely environmental exposures; they are genetically correlated social environments, and children can shape parental and sibling dynamics as well as be shaped by them. Distinguishing between variables with stronger outgoing and ingoing influence may help refine which intervention hypotheses should be prioritized, and which should be discarded or treated more cautiously.

• Hoyos, Lucía de; Schlag, Fenja; Jahagirdar, Sanjeevan; Corfield, Elizabeth Claire; Allegrini, Andrea G. & Admiraal, Danielle [Show all 95 contributors for this article] (2026). Genome-wide analysis of social behaviour across social domains, reporters and developmental stages: a meta-regression approach. Nature Human Behaviour. doi: 10.1038/s41562-026-02551-z. Full text in Research Archive Show summary

  Social behaviour is a heritable trait linked to well-being and mental health, yet it varies across social context, including social domains, informants and development, which may shape its underlying genomic architecture. Here, we conducted a genome-wide meta-regression meta-analysis of social behaviour from infancy to early adulthood, studying ~500,000 repeated measures in European-ancestry cohorts ( N  = 73,321). We modelled heterogeneity in single-variant associations across social domains (low prosocial behaviour and peer/social difficulties), multiple informants (parents, teachers and self-reports) and ages (2–29 years), identifying 6 associated loci, including variation within CADM2 ( P  = 2.51 × 10 −9 ). Single nucleotide polymorphism-based heritability ranged from 2% to 7%, and the genetic architecture comprised 4 factors reflecting differences in either social domains or informants. Polygenic scores ( N  = 16,305) accurately predicted contextual variation in independent cohorts, with some cross-ancestry transferability. Context-specific patterns of genetic correlations, particularly when estimating the developmental onset of associations, offer opportunities to disentangle shared trajectories linking social behaviour with later-life and mental health outcomes.

• Donolato, Enrica; caviola, sara; masi, alice; Lervåg, Arne & Melby-Lervåg, Monica (2026). Attitudes and emotions in the context of mathematical learning: A systematic review and meta-analysis of intervention studies. Educational Research Review. ISSN 1747-938X. doi: https:/www.sciencedirect.com/science/article/pii/S1747938X26000540. Full text in Research Archive
• Dolean, Dacian; Lervåg, Arne & Melby-Lervåg, Monica (2026). The Effectiveness of a Language ComprehensionIntervention on the Language, Reading, and Writing Skillsof Socioeconomically Disadvantaged Students. Reading Research Quarterly. ISSN 0034-0553. 61(3). doi: 10.1002/rrq.70123. Full text in Research Archive Show summary

  This pre-registered randomized controlled trial tests the impact of a language comprehension intervention on the language and literacy of 448 upper elementary Roma and non-Roma students from socioeconomically disadvantaged communities. The students from the intervention group participated in 132 language comprehension intervention sessions (designed by a research team) which focused on Tier 2 vocabulary instruction and development of expressive language skills. The control group received language instruction designed by their classroom teachers. The effects were statistically significant immediately after the intervention and 8 months later on the words taught during the intervention, and on the listening and reading comprehension of stories which included taught words. The effects on the standardized vocabulary were statistically significant immediately after the intervention only for the students with weaker initial standardized vocabulary. There was also a significant main effect on standardized vocabulary 8 months after the intervention. There were no statistically significant effects on standardized tests of word reading, written composition, listening and reading comprehension. When controlling for compliance, results showed the same pattern, but with slightly larger effect sizes. Monolingual Roma and non-Roma students improved at a similar rate on most measures, but the effects were significantly smaller for bilingual Roma students on vocabulary and listening comprehension tests which included taught words. Thus, language comprehension interventions targeting socioeconomically disadvantaged students can have limited positive effects on the language and literacy development. Future studies should examine whether more comprehensive interventions targeting broader aspects of children's lives might have more profound effects.

• Hagen, Åste Mjelve; Rogde, Kristin; Lervåg, Arne; Melby-Lervåg, Monica & Norbury, Courtenay Frazier (2026). Long-term prognosis of low language proficiency in children: Report. Cochrane Database of Systematic Reviews.
• Patsis, Panagiotis; Campos, Diego G. & Scherer, Ronny (2026). Educational inequality across countries: An integrative data analysis of TIMSS 2023 data. Studies in Educational Evaluation. ISSN 0191-491X. 91. doi: 10.1016/j.stueduc.2026.101683. Full text in Research Archive Show summary

  Socioeconomic disparities in educational achievement remain a central challenge for education systems. This study examines cross-national variation in the relation between socioeconomic status (SES) and Grade 8 mathematics achievement, using data from TIMSS 2023. Employing an integrative data analysis approach, we estimated within-school, between-school, and contextual SES effects for 43 countries and applied random-effects meta-regression to examine system-level moderators. Results show that SES is a consistent predictor of achievement within schools, while between-school SES effects were substantially larger, indicating pronounced compositional inequalities. The pooled contextual SES effect was large (ES2 = 0.85, 95% CI [0.74, 0.95]) and highly heterogeneous across countries (τ² = 0.11; Q(42) = 642.40, p < .001), ranging from negligible in Nordic systems to very large in more stratified systems. Random-effects meta-regression analyses revealed that income inequality and between-school segregation strongly predicted contextual SES effects, whereas higher levels of democratic governance were associated with weaker effects.

• Schwaba, Ted; Sullivan, Margaret L. Clapp; Akingbuwa, Wonuola A.; Ilves, Kerli; Tanksley, Peter T. & Williams, Camille M. [Show all 138 contributors for this article] (2026). Robust inference and correlates from genetic associations with personality. Nature. ISSN 0028-0836. doi: 10.1038/s41586-026-10992-9. Full text in Research Archive
• Demange, Perline Aline Delle; Nivard, Michel G.; Torvik, Fartein Ask; Eilertsen, Espen Moen; Cheesman, Rosa Catherine Gillespie & Nordmo, Magnus [Show all 9 contributors for this article] (2026). No evidence of parental mental health influencing children’s academic achievement: a within-family study. European Child and Adolescent Psychiatry. ISSN 1018-8827. doi: 10.1007/s00787-026-03100-9. Full text in Research Archive Show summary

  Children of parents with psychopathology generally perform less well in school than their peers. Parental symptoms might not, however, account for their lower achievement, as other familial factors might contribute. To examine the role of parental symptoms, we analyse data from 9,000 families in the Norwegian Mother, Father, and Child Study (MoBa). Parents reported their symptoms of anxiety, depression, ADHD, eating disorders, and alcohol use disorder during pregnancy and during their child’s childhood. Children in 5th grade (aged 10) completed nationally-standardised tests of mathematics, reading comprehension, and English (as an additional language). Comparing children who are cousins (children-of-siblings design), we controlled for unmeasured factors shared among family members that confound the relationship between parental mental health and children’s academic achievement. We found small associations between greater parental symptoms and lower scores in reading and mathematics (− 0.060 ≤ β ≤ −0.013). However, these associations were no longer significant when comparing cousins whose parents differ in mental health. Results suggest that parental symptoms do not exert a direct, clinically meaningful effect on children’s academic achievement. Although non-significant, associations with parental symptoms measured close to the child’s academic test are less attenuated than those measured during pregnancy. Notably, comparison between the overall MoBa sample and the children-of-siblings samples suggests ascertainment differences that hinder strong generalisations. Our findings underscore the importance of quasi-experimental family designs in identifying modifiable targets in intergenerational health and education research. Supporting parental mental health is crucial but its direct effect on children’s achievement may be smaller than often thought.

• Bright, Joanna K.; Ahmadzadeh, Yasmin I.; Oginni, Olakunle; Viding, Essi; Leve, Leslie D. & Neiderhiser, Jenae M. [Show all 11 contributors for this article] (2026). Triangulating evidence for genetic and environmental components of associations between parental behaviours and aggressive behaviour in children. Nature Communications. 17(1). doi: 10.1038/s41467-026-75095-5. Full text in Research Archive Show summary

  Parenting behaviours are often linked to childhood aggression, but many studies fail to account for shared genetics or test directionality. Using family-based designs, we control for genetic confounding and examined bidirectional effects across two samples. First, we apply a children-of-twins/siblings design in the Norwegian Mother Father and Child Cohort Study which uses genetic relatedness between family members to separate genetic and environmental components of parent-child associations. Second, we use longitudinal models in the USA-based Early Growth and Development Study, an adoption sample where parents and child are not genetically related, enabling estimation of parent-child associations without genetic confounding. Across both studies, we find evidence for genetic and environmental transmission between parenting and child aggression. We show significant child-to-parent effects on inconsistent discipline in both samples. In the children-of-twins analysis, the association between positive parenting and child aggression is shown to be due to shared genetics, where no statistically significant association is observed in the adoption sample. These findings build on the growing body of literature showing genetic influences on both aggression and parenting behaviours, whilst underscoring the value of triangulation.

• Bond, Tom A.; McAdams, Tom A.; Warrington, Nicole Maree; Hannigan, Laurie; Eilertsen, Espen Moen & Ayorech, Ziada [Show all 12 contributors for this article] (2026). Parental body mass index and offspring childhood body size and eating behaviour: A structural equation modelling analysis in the Norwegian Mother, Father and Child Cohort Study. PLoS Medicine. ISSN 1549-1277. 23(6). doi: 10.1371/journal.pmed.1005094. Full text in Research Archive Show summary

  Background The intergenerational transmission of obesity-related traits could propagate an accelerating cycle of obesity, if parental adiposity causally influences offspring adiposity. The extent to which intergenerational obesity associations are due to such causal effects, as opposed to genetic confounding (inheritance), is unclear. We aimed to establish whether associations between parental peri-pregnancy body mass index (BMI) and offspring birth weight (BW), BMI until 8 years of age, and 8-year-old eating behaviour are due to genetic confounding. Methods and findings Data were from the Norwegian Mother, Father and Child Cohort Study, a prospective population-based birth cohort born between 1999 and 2009 at 50 out of 52 hospital maternity units in Norway. We compared the strength of the associations of maternal pre-pregnancy BMI versus paternal BMI during pregnancy, with offspring outcomes including birth weight and BMI assessed between age 6 months and 8 years of age, and appetite-related eating behaviour traits assessed at age 8 years via the Child Eating Behaviour Questionnaire (CEBQ), adjusting for potential confounders including parity, parental/grandparental language group and parental age, smoking, education and income). We then used an extended children of twins structural equation model (SEM) to quantify the extent to which associations were due to genetic confounding. Up to 85,866 children (51.3% male) were included in linear regression models, whereas SEM models included up to 50,999 children. Maternal BMI was more strongly associated than paternal BMI with offspring BW, but the maternal-paternal difference decreased for offspring BMI after birth. Greater parental BMI was associated with obesity-related offspring eating behaviours. SEM results indicated that genetic confounding did not explain the association between parental BMI and offspring BW, but explained the majority of the association with offspring BMI from 6 months onwards. For 8-year BMI, genetic confounding explained 79% (95% CI [62, 95]; p = 1.9 × 10−12) of the covariance with maternal BMI and 94% (95% CI [72, 113]; p = 2.7 × 10−14) of the covariance with paternal BMI. Limitations of this study include selective recruitment and attrition, potential bias due to parental assortative mating, and that findings may not generalise beyond high-income country settings with high obesity prevalence. Conclusions We found strong evidence that parent–child BMI associations may primarily be due to genetic confounding. When considered alongside prior evidence, this finding may argue against a strong causal effect of maternal or paternal adiposity on childhood adiposity via intrauterine or periconceptional mechanisms.

• Bjørndal, Ludvig Daae; Hegemann, Laura Elizabeth; Pettersen, Johanne Hagen; Corfield, Elizabeth Claire; Hannigan, Laurie & Yilmaz, Zeynep [Show all 14 contributors for this article] (2026). Investigating Relationships Between Genetic Risk, Childhood Maltreatment, and Eating Disorders in Women. Biological Psychiatry: Global Open Science. 6(5). doi: 10.1016/j.bpsgos.2026.100761. Full text in Research Archive Show summary

  Background Genetic and environmental factors contribute to eating disorder risk, yet their interplay is poorly understood. We examined whether childhood maltreatment and polygenic scores for anorexia nervosa (PGS-AN) and binge-eating broad (PGS-BEB) are associated with eating disorders. We also examined the interactions between childhood maltreatment and PGSs in predicting eating disorders. Methods This nested case-control study used data from up to 63,989 mothers in the MoBa (Norwegian Mother, Father and Child Cohort Study). Mothers reported on their own experiences of 4 childhood maltreatment types: long-term humiliation or degradation, threats to self or someone close, physical abuse, and sexual abuse. Diagnoses of AN, bulimia nervosa (BN), binge-eating disorder (BED), purging disorder (PD), and binge-eating spectrum disorders (BESP) were obtained using self-report data from 5 time points and population health registers. Results The prevalence of AN, BN, BED, PD, and BESP was 2.19%, 4.15%, 10.39%, 0.60%, and 12.96%, respectively. All childhood maltreatment types were strongly associated with elevated eating disorder likelihood (with odds ratios [ORs] ranging from 1.71 to 3.29) as were eating disorder PGSs (with ORs ranging from 1.05 to 1.31). There were no multiplicative interaction effects between childhood maltreatment and PGSs. Small additive interactions were observed between PGS-AN and PGS-BEB and degradation/humiliation for BN and BESP in exploratory analyses. Conclusions Eating disorder PGSs and childhood maltreatment are associated with higher odds of eating disorders. Furthermore, we found tentative evidence of small additive interaction effects between polygenic liability and childhood maltreatment, suggesting that their combined influence further elevates the risk of some eating disorders.

• Wechsler, Daniel L.; Eilertsen, Espen Moen; Ahmadzadeh, Yasmin I.; Cheesman, Rosa Catherine Gillespie; Adamo, Nicoletta & Hannigan, Laurie [Show all 8 contributors for this article] (2026). Direct and Indirect Genetic Effects on Child ADHD Traits in Early and Mid-Childhood: Trio Genome-Wide Complex Trait Analyses in a Large Norwegian Birth Registry Cohort. Behavior Genetics. ISSN 0001-8244. 56(4), p. 184–193. doi: 10.1007/s10519-026-10273-1. Full text in Research Archive Show summary

  Genetic variants in family members may exert environmentally mediated indirect genetic effects on children’s attention-deficit hyperactivity disorder (ADHD) traits. We set out to quantify the indirect genetic effects of parents’ genotypes on children’s ADHD traits as measured in early and mid-childhood. We analyzed data from genotyped trios of children, mothers, and fathers of European ancestry from the Norwegian Mother, Father and Child Cohort Study (MoBa) birth cohort. Child ADHD data were available for analytic subsamples of 12,374 trios at age 5 (children 50.5% male), and 12,714 trios at age 8 (children 50.9% male). We quantified direct genetic effects of children’s genotype and indirect effects of mothers’ and fathers’ genotypes on children’s ADHD traits at each age. Differing patterns of direct and indirect genetic effects were observed in early and mid-childhood, with predominantly maternal indirect genetic effects on ADHD traits at age 5, and roughly equal direct genetic effects and maternal indirect effects on ADHD traits at age 8. However, large standard errors hindered confident inference as to the relative importance of specific effects, and model fit comparisons ultimately favored models with no indirect genetic effects at age 5 and 8, as well as no direct genetic effects at age 5. We do not find clear evidence of indirect genetic effects of maternal or paternal genotype on child ADHD traits at ages 5 and 8, nor direct genetic effects on child ADHD traits at age 5. While previous findings of indirect genetic effects on ADHD subdomains at ages 3 and 8 broadly support the plausibility of indirect genetic effects operating on total ADHD scores at ages 5 and 8, it appears that indirect genetic effects on overall ADHD trait magnitude may be more difficult to estimate with precision than subdomain-specific effects.

• Ulitzsch, Esther; Nestler, Steffen; Johnson, Sverre Urnes; Snuggerud, Therese Ruud & Lüdtke, Oliver (2026). Capturing Heterogeneity in Levels, Variability, and Couplings across Persons and Time with a Hierarchical Time-Varying Coefficient Formulation of the Multivariate Normal. Psychometrika. ISSN 0033-3123. doi: 10.1017/psy.2026.10125. Full text in Research Archive Show summary

  Time-varying coefficient modeling (TVCM), which represents regression coefficients as smooth functions of continuous time, provides a flexible framework for uncovering complex patterns of change in levels and associations in intensive longitudinal data. However, conventional TVCM remains limited to investigating directional effects across individuals. By introducing a TVCM formulation of the multivariate normal distribution, the present study extends TVCM to explore change in undirected associations (couplings) and variability, thereby broadening its utility for psychological research. We discuss three versions of this approach: an aggregate-level model and two hierarchical versions capturing interindividual differences in unfolding change, either via person-specific intercepts accounting for onset differences or through fully person-specific coefficient functions smoothed via partial pooling. To illustrate the proposed developments, we apply them to six weeks of intensive longitudinal data from 16 anxiety patients undergoing therapy and examine unfolding changes in the level and volatility of nervousness and threat monitoring, their coupling, as well as between-person heterogeneity in each of these. We further show how inspecting first-order derivatives of the coefficient functions supports identifying periods of stability and change. Finally, we discuss extensions incorporating person-level characteristics to explain heterogeneity in patterns of change and predict outcomes.

• Porneso, Ralph; Havdahl, Alexandra; Eilertsen, Espen Moen & Ystrom, Eivind (2026). Longitudinal genome-wide analysis reveals putative non-additive loci in trait development. Cell reports. 45(8). doi: 10.1016/j.celrep.2026.117840. Full text in Research Archive Show summary

  Complex traits emerge from reciprocal interactions among genotype, environment, and developmental processes. Yet, standard genetic models assume purely additive effects, potentially obscuring non-additive effects. Here, we introduce a longitudinal log-linear variance and genotype-by-time model to detect associations from within-individual variation departing from additivity, i.e., putative non-additive effects. Applied to early growth (infant length and BMI) and cognitive traits (math and reading) of 45,000 to 65,000 individuals, we report 76 lead putative non-additive loci that are enriched 16-fold for cis-regulatory interactions. Of the 76, 6 overlap prior interaction studies (anthropometric) and only 3 loci overlap prior genome-wide association study (GWAS) (cognitive). Accounting for scale effects and linkage disequilibrium (LD), we observe that additive effects are correlated with putative non-additive effects, i.e., “effect pleiotropy.” These results are consistent with non-additive genetic contribution to trait development, which may partly be absorbed by effects estimated under standard GWAS parameterization that assumes strict additivity.

• Rayner, Christopher; Hannigan, Laurie; Badini, Isabella; Demange, Perline Aline Delle; Ofstad, Sverre Berg & Ystrøm, Eivind [Show all 7 contributors for this article] (2026). Quantifying and adjusting for selection biases in the Norwegian Mother, Father and Child Cohort Study using population-wide individual-level registry information. International Journal of Epidemiology. ISSN 0300-5771. 55(4). doi: 10.1093/ije/dyag122. Full text in Research Archive Show summary

  Background Selective participation in research studies hampers researchers’ ability to draw valid and generalizable inferences from analyses. Quantifying and adjusting for selective participation are desirable but can be challenging given the paucity of data for non-participants. Methods We used individual-level information from population registers to predict baseline and continued participation in the Norwegian Mother, Father and Child Cohort Study (MoBa). Inverse probability weights were computed from logistic regression models with elastic-net regularization. We predicted selective participation and attrition in 296 987 mothers, of whom 29% returned the first MoBa questionnaire and 12.5% returned a follow-up questionnaire 8 years later. To quantify bias, we computed sample characteristics and exposure–outcome associations in the target population and stratified samples. To compare approaches for adjusting for bias, we computed weighted sample estimates by using three sets of weights. Results Unweighted sample estimates were systematically different from target-population values, indicating bias due to selective participation. Baseline participation weights substantially reduced the impact of selection bias on mean values by 93% and associations by 75%. Attrition weights reduced attrition bias on mean values by 78% and associations by 50% but were less effective for reducing participation bias (22% and 14% respectively). Conclusion In this sample, characteristics and effect estimates are substantially different from target-population values. Participation weights were relatively effective at reducing bias due to selective participation but attrition weights were not. Estimates from studies that use attrition weights may still contain non-negligible selection bias—particularly if the baseline sample is not representative of the target population. Future studies should prioritize opportunities for deriving sampling weights for participation as well as attrition.

• Hagen, Åste Marie Mjelve; Rogde, Kristin; Lervåg, Arne Ola; Melby-Lervåg, Monica & Norbury, Courtenay Frazier (2026). Long-term prognosis of low language proficiency in children. The Cochrane library. doi: 10.1002/14651858.cd015268.pub2. Full text in Research Archive Show summary

  Background Low language proficiency (LLP) affects up to 10% of children, depending on how it is defined, and is a known risk factor for academic and social difficulties. Despite growing awareness, there is limited consensus on the long‐term consequences of LLP across quality of life domains. This review synthesises evidence from longitudinal cohort studies to evaluate long‐term risks associated with LLP identified between ages four and eight, with follow‐up from age 12 onwards. Objectives To examine the long‐term outcomes of children aged four to eight years with low language proficiency (LLP), in terms of language, literacy, and quality of life across five WHO domains (physical, psychological, independence, social relationships, and environment). Search methods CENTRAL, MEDLINE, Embase, PsycINFO, ERIC, and 17 other databases were searched without language or date restrictions. In addition, reference lists were checked, citation searching was conducted, and study authors were contacted to identify additional studies. The most recent search was completed in March 2025. Selection criteria We included prospective or retrospective longitudinal cohort studies that identified children with LLP between ages four and eight years and assessed outcomes at age 12 or older. Studies could include comparison groups or single‐cohort designs. LLP was defined either using standardised diagnostic criteria (≤ –1 SD on normed language measures, encompassing ~10–15% of the population) or clinical judgement by qualified professionals. Data collection and analysis We extracted data on language, literacy, and World Health Organization (WHO) quality of life domains and used robust variance estimation (RVE) meta‐analysis models, including hierarchical and correlated effects models. Effect sizes were reported as Hedges' g or risk ratios (RR), with Grading of Recommendations, Assessment, Development and Evaluation (GRADE) applied to each outcome domain. We conducted sensitivity and moderator analyses and assessed small‐study effects. Main results We included 80 studies; 72 contributed to meta‐analyses across 15 independent cohorts (≈ 28,828 participants). Studies were published between 1982 and 2024 and conducted in Europe and North America. Risk of bias, assessed across study participation, attrition, and outcome measurement, varied; only three studies were at low risk across all assessed domains, with study attrition most frequently rated as moderate or high. Language outcomes showed large adverse associations in long‐term follow‐up (145 effect sizes; 11 cohorts; Hedges’ g = –1.36, 95% Confidence Interval (CI) –1.80 to –0.92; moderate certainty). Literacy outcomes were similarly affected (86 effect sizes; 7 cohorts; g = –1.12, 95% CI –1.28 to –0.96; high certainty). Physical outcomes were reported in only one study and could not be meta‐analysed; evidence was insufficient to draw conclusions. Psychological outcomes showed moderate adverse associations (91 effect sizes; 7 cohorts; g = –0.50, 95% CI –0.80 to –0.19; moderate certainty), with risk ratio analyses indicating lower probability of favourable psychological outcomes (RR = 0.53, 95% CI 0.42 to 0.67). Independence outcomes showed smaller and more uncertain associations (17 effect sizes; 2 cohorts; g = –0.59, 95% CI –1.35 to 0.18; low certainty). Social relationship outcomes showed moderate adverse associations (35 effect sizes; 6 cohorts; g = –0.64, 95% CI –1.35 to 0.07; moderate certainty). Environmental outcomes showed large but imprecise adverse associations (23 effect sizes; 5 cohorts; g = –1.10, 95% CI –1.47 to –0.73; moderate certainty). Across domains, sensitivity analyses supported the robustness of findings, although degrees of freedom were often low due to the limited number of independent cohorts. Where binary outcome data were available, risk ratio estimates were directionally consistent with continuous outcomes but frequently imprecise. Authors' conclusions Early low language proficiency (LLP) is consistently associated with substantial long‐term language and literacy difficulties. LLP is also associated with poorer psychological well‐being and social relationship outcomes later in life, with moderate certainty of evidence. Associations with independence outcomes are smaller and more uncertain, reflecting limited data and low certainty. Environmental outcomes, including education, employment, and societal participation, show large adverse associations, although estimates are imprecise due to the small number of contributing cohorts. Physical health outcomes remain under‐researched. Taken together, these findings indicate that childhood LLP is not a transient delay but a marker of enduring developmental vulnerability, underscoring the need for sustained identification and support across developmental stages. Further high‐quality longitudinal studies are needed, particularly in under‐represented outcome domains.

• Krätschmer, Ilse; Hegemann, Laura Elizabeth; Hofmeister, Robin J.; Corfield, Elizabeth Claire; Mahmoudi, Mahdi & Delaneau, Olivier [Show all 14 contributors for this article] (2026). Separating direct, indirect, and parent-of-origin genetic effects in the human population. Cell Genomics. 6(7). doi: 10.1016/j.xgen.2026.101277. Full text in Research Archive Show summary

  We introduce JODIE, a genetic joint modeling approach that estimates how DNA loci influence human traits by partitioning genetic effects into four components: direct effects (from a child’s alleles), indirect maternal and paternal effects (from parents’ alleles), and parent-of-origin (PofO) effects (dependent on parental transmission of alleles), while uniquely accounting for assortative mating. We analyze 30,000 child-mother-father trios from the Estonian Biobank and the Norwegian Mother, Father, and Child Cohort, focusing on height, body mass index, and childhood educational test scores. We find direct effects to be the largest contributor to trait variation, but combined, indirect parental and PofO effects are similarly substantial. We support our results by within-family genome-wide association testing and identify 276 independently associated DNA regions with a complex interplay between direct, indirect, and PofO effects. By joint modeling, we show that direct, indirect, and PofO effects collectively shape human phenotypic variation across loci genome-wide.

• Veletić, Jelena; Steinmann, Isa & Nilsen, Trude (2026). Teacher job satisfaction: International stability over 16 years and associations with school climate changes. Teaching and Teacher Education : An International Journal of Research and Studies. ISSN 0742-051X. 181. doi: 10.1016/j.tate.2026.105670. Full text in Research Archive Show summary

  In response to growing international attention to teacher retention and workforce sustainability, organizations such as UNESCO have identified teacher shortages as a major policy issue, with declining job satisfaction as a potential contributing factor. Using data from TALIS cycles 2008‒2024, this study investigates (1) if average teacher job satisfaction has changed internationally over the past 16 years, and (2) if teacher job satisfaction changes are associated with changes in school climate at the country level. Such associations with school environmental factors could help explain changes in job satisfaction. Utilizing country-fixed effects regression, the analyses account for time-invariant between-country differences and isolate international and country-specific trends. The results indicate that internationally, teacher job satisfaction increased between 2008 and 2013 and remained relatively stable thereafter. Improvements in certain aspects of school climate, especially relationships between students and teachers, are associated with increasing teacher job satisfaction at the country level.

• Romero, Sandra; Georgiou, George K.; Altani, Angeliki & Protopapas, Athanassios (2026). Examining the Serial Advantage in Fluent and Dysfluent Readers. Dyslexia. ISSN 1076-9242. 32(3). doi: 10.1002/dys.70033. Full text in Research Archive Show summary

  We examined how the relation between serial and discrete reading/naming rate reveals cognitive processes that underlie reading fluency success and failure. Our sample included 87 children scoring above the 35th percentile (fluent readers) and 36 scoring below the 16th percentile (dysfluent readers) on a word‐reading fluency test. All children were in Grade 3 and had adequate reading accuracy (standard score above the 25th percentile). The experimental tasks included serial and discrete reading of one‐syllable, high‐frequency words and serial and discrete digit naming. The results showed that all children performed better in the serial than the discrete naming/reading tasks. The fluent readers outperformed the dysfluent readers in all tasks. Moreover, among the fluent readers, serial reading was best predicted by serial naming. In contrast, serial reading was best predicted by discrete word reading among the dysfluent readers. Overall, the findings indicate that among readers with adequate accuracy, differences in fluency are associated with whether multiword reading aligns more strongly with serial naming or with individual word recognition, suggesting that dysfluent performance may reflect greater reliance on item‐by‐item processing and reduced efficiency in coordinating processing across successive words.

• Edvoll, Maud Clemson; Folstad, Siri Hausland; Eftedal, Nikolai Haahjem; Poornikoo, Mehdi; Fang, Yuan & Ystrøm, Eivind [Show all 11 contributors for this article] (2026). A Norwegian curriculum reform: Effects for 10th graders’ academic performance. Studies in Educational Evaluation. ISSN 0191-491X. 89. doi: 10.1016/j.stueduc.2026.101616. Full text in Research Archive
• Brodeur, Abel; Mikola, Derek; Cook, Nikolai; Fiala, Lenka; Brailey, Thomas & Briggs, Ryan [Show all 347 contributors for this article] (2026). Reproducibility and robustness of economics and political science research. Nature. ISSN 0028-0836. 652, p. 151–156. doi: 10.1038/s41586-026-10251-x. Full text in Research Archive Show summary

  Science aspires to be cumulative. Reproducibility efforts strengthen science by testing the reliability of published findings, promoting self-correction, and informing policy-making1. Computational reproductions, whereby independent researchers reproduce the results of published studies, are an essential diagnostic tool2–10. Such efforts should have greater visibility11–16. However, little social science reproduction and robustness has been conducted at scale10,13,17–23. Here we reproduced original analyses and conducted robustness checks of 110 articles that were published in leading economics and political science journals with mandatory data and code sharing policies17,18. We found that more than 85% of published claims were computationally reproducible. In robustness checks, our reanalyses showed that 72% of statistically significant estimates remain significant and in the same direction, and the median reproduced effect size is nearly the same as the originally published effect size (that is, 99% of the published effect size). Additionally, 6 independent research teams examined 12 pre-specified hypotheses about determinants of robustness. Research teams with more experience found lower levels of robustness, and robustness did not correlate with author characteristics or data availability. Robustness checks and reproduction of analyses with existing and updated data based on 110 articles in economics and political science journals with data and code-sharing requirements found high levels of&nbsp;robustness and reproducibility and determined that robustness was not dependent on author characteristics or data availability.

• Teo, Timothy; Scherer, Ronny; Fung, Artemis Sze Kok & Fung, Cynthia Sze Ling (2026). Factors Associated with Students’ Adoption of Artificial Intelligence Technology in Tertiary Education: A Meta-Analytic Review. Educational Research Review. ISSN 1747-938X. doi: 10.1016/j.edurev.2026.100804. Full text in Research Archive Show summary

  This meta-analytic review synthesizes evidence on factors shaping post-secondary students’ adoption of artificial intelligence (AI) through a multilevel meta-analysis of 233 correlations from 32 studies (N = 16,977). A three-level model with correlated effects was identified as the optimal approach, yielding moderate positive weighted average correlations for individual (r = .57), contextual (r = .53), and technological factors (r = .50). No single category dominates adoption. Among specific predictors, usage intentions emerged as the strongest predictor (r = .64). Interestingly, perceived risks and trust showed weaker associations. Within the three broad categories of factors, the correlations exhibited large overall heterogeneity (I-squared >98%), which could be partly explained by the diversity of constructs and the students’ experience with AI. For practice, integration of AI should target specific constructs (e.g., learning objectives, intentions) and adapt to students’ experience levels. For research, the field over-relies on traditional technology acceptance models (e.g., TAM, UTAUT) and neglects AI-specific factors (e.g., anthropomorphism, ethics). Addressing this gap is important for advancing theory and evidence-based policy.

• Pietsch, Marcus; Eryilmaz, Nurullah; Strietholt, Rolf; Scherer, Ronny; Nascimento, Matheus Monteiro & Abels, Simone [Show all 7 contributors for this article] (2026). Endangering Just Sustainabilities: An IPD Meta-Analysis on the Social Stratification of Youth Environmental Attitudes in 65 Countries. Journal of Environmental Psychology. ISSN 0272-4944. 112. doi: 10.1016/j.jenvp.2026.103085. Full text in Research Archive Show summary

  This study examines global socioeconomic inequality in environmental attitudes among young people. Using novel data from an international study of nearly 700,000 individuals across 65 countries, we combine a two-stage individual participant data (IPD) meta-analysis with a machine learning (Meta-CART) approach to examine cross-national variation in inequality in environmental attitudes and its associations with the macrostructural dimensions of capacity, distribution, and institutional openness. Higher socioeconomic status (SES) is consistently associated with stronger environmental preservation attitudes in both primary and secondary school. However, the strength of this relationship varies across countries. Revealing a structural paradox, press freedom and gross domestic product (GDP) interact to moderate SES disparities: the largest gaps appear in nations with both high institutional openness and affluence. Contrary to expectations, GDP and academic freedom do not exert consistent linear effects. The results suggest that national conditions shape the social distribution of environmental attitudes and that institutional enablers of knowledge may reinforce environmental engagement among advantaged youth, challenging the equity aspirations of sustainability education.

• Zelihic, Dzan; Ziaka, Laoura; McMurray, Bob; Altani, Angeliki; Simonsen, Kristin & Protopapas, Athanassios (2026). Children's visual word recognition is hampered by adjacent stimuli. Cognition. ISSN 0010-0277. 274. doi: 10.1016/j.cognition.2026.106581. Full text in Research Archive Show summary

  Although skilled readers make use of information about words adjacent to the fixated word, developing readers are known to be limited in their uptake of parafoveal information, leading to the expectation that they may be entirely insensitive to the presence of adjacent stimuli. However, lack of benefit from nearby items does not imply that those items cannot negatively impact the recognition process. Here we report two experiments with 62 Norwegian children attending Grade 2 and 141 in Grade 5 using a modified version of the visual world paradigm with masked flanked visual word targets. Compared to a baseline condition with no flankers, we found that the presence of flanking words or unfamiliar-font strings interfered with lexical activation of the foveated target word; in contrast, strings of repeated symbols had no effect. The results were very similar for the two grades, except that the more advanced readers also exhibited an interaction of flanking condition with target word frequency, specifically, smaller frequency effects when flanked by words; these were interpreted as foveal load effects. The findings indicate that adjacent stimuli are to some extent simultaneously processed along with the foveated word and strongly interfere with it, from the earliest stages and throughout reading development. We propose that management of interference from adjacent words is a major factor modulating the development and expression of reading skill.

• Teig, Nani; Ye, Wangqiong; Caro, Daniel & April, Daniel (2026). Academic resilience of disadvantaged students in 58 countries: The role of early home learning activities and instructional clarity. Studies in Educational Evaluation. ISSN 0191-491X. 89. doi: 10.1016/j.stueduc.2026.101604. Full text in Research Archive Show summary

  Academic resilience refers to students’ ability to succeed academically despite socioeconomic adversity. This study investigates how early home learning activities and teachers’ instructional clarity interact to support disadvantaged students’ resilience in mathematics and science. Using data from 308,609 fourth graders across 58 countries in the Trends in International Mathematics and Science Study (TIMSS) 2019, resilient students were identified with both cross-national and within-country thresholds. Results show large variation across countries and subjects, with mathematics generally yielding higher resilience share than science. Pooled moderation analyses revealed compensatory effects: instructional clarity was especially beneficial for students with limited early home learning, while within-country analyses more often showed synergistic effects, where both supports reinforced one another. These findings underscore that resilience is context-specific and shaped by the alignment between home and school environments. Policymakers and educators should strengthen both supports individually while fostering their complementarity to enhance disadvantaged students’ resilience in mathematics and science.

• Fütterer, Tim; König, Lars; Campos, Diego Gonzalez; Scherer, Ronny; Zitzmann, Steffen & Hecht, Martin (2026). Fast-Track Your Abstract Screening: Mastering ASReview for Accelerating Abstract Screening and Evaluating Decisions From Automatic-Screening Methods. Advances in Methods and Practices in Psychological Science (AMPPS). ISSN 2515-2459. 9(2), p. 1–36. doi: 10.1177/25152459261442150. Full text in Research Archive Show summary

  Research syntheses, such as systematic reviews and meta-analyses, are crucial for synthesizing research to support evidence-based decision-making. However, the abstract-screening phase, during which researchers evaluate titles and abstracts for inclusion, is highly time-consuming and often results in cognitive biases and fatigue. To address these challenges, machine-learning-assisted tools, particularly those using active learning, have gained prominence. One such tool is Active Screening Review (ASReview), an open-source software for semiautomating title and abstract screening in systematic reviews. ASReview incorporates user feedback to prioritize relevant studies, reducing screening time and improving efficiency. Despite its potential, many researchers remain uncertain about integrating ASReview into their workflows and making evidence-based decisions regarding the tool’s configuration, training, and stopping criteria. In this tutorial, we provide a step-by-step guide to using ASReview, including practical examples from psychological research. We demonstrate the software’s application in two use cases: screening unlabeled abstracts using active learning and verifying results from automated-screening methods. In the tutorial, we also offer evidence-based recommendations for selecting stopping rules to balance sensitivity and efficiency. We also outline strategies for prescreening, data-set preparation, model setup, and progress monitoring to ensure that researchers can maximize the tool’s benefits while maintaining scientific rigor. By offering evidence-based guidance at each stage of the process for practitioners without coding skills, in this tutorial, we aim to help researchers harness artificial-intelligence-aided screening to enhance the quality and efficiency of research syntheses across disciplines.

• Widding-Havnerås, Tarjei; Demange, Perline Aline Delle; Zachrisson, Henrik Daae; Borgen, Nicolai; Ystrøm, Eivind & Elwert, Felix (2026). Estimating returns to education using the genetic lottery. Proceedings of the National Academy of Sciences of the United States of America (PNAS). ISSN 0027-8424. 123(15), p. 1–10. doi: 10.1073/pnas.2537049123. Full text in Research Archive Show summary

  Does more schooling cause higher lifetime earnings? Social scientists have long sought to determine the economic returns to schooling given its importance to individual life chances and public policy. Prior estimates are limited by unobserved confounding in observational studies and the focus of popular quasi-experimental studies on increases in schooling at only one particular age. Genotyped data offer an opportunity to address unobserved confounding and to estimate the returns to an additional year of schooling at any age by using quasi-randomly assigned genetic variants related to education as instrumental variables [Mendelian randomization (MR)]. We analyze comprehensive Norwegian population registries with career-long earnings data and genotyped data from the Norwegian Mother, Father and Child Cohort Study (MoBa). We employ three identification strategies for triangulation: ordinary least squares (OLS) with covariate-adjustment, sibling and twin fixed-effects models, and MR. Estimated returns to schooling are 8.0% in MR (N = 109,800) and 6.3% in sibling-MR (N = 18,666). Extensive sensitivity analyses suggest that MR results are robust even to large potential violations of MR assumptions, including pleiotropy. MR estimates somewhat higher returns than OLS for the full population (5.9%, N = 1,255,604) and fixed-effects models for siblings (5.3%, N = 966,976) or monozygotic twins (3.2%, N = 2,630). The estimated internal rate of return to schooling exceeds opportunity costs of education as proxied by the market interest rate. The lifetime returns to schooling are positive and substantial across all models.

• Chegeni, Razieh; Nes, Ragnhild Bang; Cheesman, Rosa Catherine Gillespie; Ayorech, Ziada; Ystrøm, Eivind & Røysamb, Espen (2026). Direct and indirect parental genetic effects on offspring susceptibility to internalizing problems across development. Nature Mental Health. 4, p. 754–765. doi: 10.1038/s44220-026-00619-3. Full text in Research Archive Show summary

  Internalizing problems, including symptoms of anxiety and depression, are common in childhood and adolescence and are linked to adverse long-term outcomes. Although both child genetic variants and parental genetic influences contribute to these problems, the specific direct (child) and indirect (parental) genetic pathways involved remain unclear. We applied multi-polygenic score models using elastic net regression to identify key genetic predictors of depressive and anxiety symptoms at ages 8 and 14 in 9,314 parent–child trios from the Norwegian Mother, Father and Child Cohort Study. We included 90 polygenic scores (PGSs) for the trio, along with their respective interaction terms. Predictive accuracy improved with age, with models explaining up to 2.7% of the variance in depression and 1.2% in anxiety. Key predictors included child attention deficit hyperactivity disorder, cognitive skills and well-being spectrum PGSs; maternal PGSs for smoking and cognitive skills; and paternal well-being spectrum PGSs. These findings underscore the value of incorporating diverse parental genetic traits to understand intergenerational risk transmission and developmental changes in child mental health.

• Ofstad, Sverre Berg; Tan, Tony & Andersson, Björn (2026). Comparing the difficulty of elective subjects in high school using a population-based Norwegian registry. Scandinavian Journal of Educational Research. ISSN 0031-3831. doi: 10.1080/00313831.2026.2648976. Full text in Research Archive Show summary

  When grade point averages (GPAs) are used for admission into tertiary education, there is an implicit assumption that any two identical GPAs convey the same level of academic competency. However, this assumption does not hold when students are free to choose elective subjects and there are differences in their difficulty and dimensionality. In this study, we utilized item response theory to examine dimensionality and difficulty of 11 elective subjects in Norwegian high school, while accounting for self-selection bias, using data from 21,666 third year students. Our results show that the GPA is best represented as a multidimensional construct. Additionally, we demonstrate that the selection bias in observed subject grade averages for electives conceals considerable differences in difficulty levels. Hence, the GPA of Norwegian high school students does not only reflect academic competency but also the decisions made regarding which elective subjects to take.

• Pettersen, Johanne Hagen; Eilertsen, Espen Moen; Hegemann, Laura Elizabeth; Hannigan, Laurie; Lund, Ingunn Olea & Johannessen, Pia Myklebust [Show all 12 contributors for this article] (2026). Intra-familial dynamics of mental distress during the Covid-19 lockdown. Translational Psychiatry. 16(1), p. 1–9. doi: 10.1038/s41398-026-03876-z. Full text in Research Archive Show summary

  Lockdowns and social restrictions imposed in response to the Covid-19 pandemic intensified the proximity and reciprocal exposure among members of nuclear families. It is unclear how variation in mental distress during this period is attributed to potential influences of family members. This study used genetic data from adolescents (n = 4 388), mothers (n = 27 852) and fathers (n = 25 953), to disentangle the contributions of parent-driven, child-driven, and partner-driven components to mental distress during the first two months of the Covid-19 lockdown. Separate models also included adolescents’ non-pandemic mental distress as outcomes (n = 13 484). Trio genome-wide complex trait analyses separated two types of genetic components; direct–how an individual’s genotype is associated with their own mental distress, and indirect–how an individual’s genotype is associated with the mental distress of family members. A trio polygenic score (PGS) design was used to investigate associations of specific genetic liability factors with mental distress, and whether these changed over time (PGS×time). Results suggest that family-level genetic factors contribute to mental distress; variance components capturing indirect genetic effects accounted for 10% of adolescent mental distress (mother-driven), 2–3% of maternal (partner-driven), and 5% of paternal mental distress (child-driven). Mothers’ depression and ADHD PGS were positively associated with fathers’ mental distress. No PGS×time interactions were found. Direct genetic effects accounted for 9–10% variance in mental distress across family members, partly explained by genetic variants associated with anxiety, depression, ADHD and neuroticism. These findings highlight the importance of family dynamics and emphasize the potential value of including family members in mental health interventions.

• Ye, Wangbei & Ye, Wangqiong (2026). Do school quotas improve rural access to elite high schools? Evidence from a county-level city in China. International Journal of Educational Development. ISSN 0738-0593. 123. doi: 10.1016/j.ijedudev.2026.103571. Full text in Research Archive Show summary

  This study examines the effects of a high school quota allocation policy in a county-level city in China, focusing on its role in promoting educational equality while maintaining academic quality. We combined quantitative data from standardized Grade 8 examination results of 2320 students across all eight middle schools in the county with qualitative interviews conducted with education bureau officials, principals, and teachers. Quantitative analyses included independent-sample t tests, an equity-efficiency framework, and regression discontinuity design (RDD), while thematic analysis of interviews provided contextual insights into local practices and policy implementation. Three key findings emerged. First, substantial rural-urban disparities in student performance persist. Urban students outperformed their rural peers, and girls scored higher than boys in Chinese and English, though gender differences in mathematics and physics were not significant. Second, the 70% quota policy modestly expanded opportunities for rural students to enter elite high schools, but gains were uneven across schools and shaped largely by enrollment size rather than education quality. Third, the policy safeguarded academic standards, as admission scores remained stable and RDD confirmed that admitted students were academically stronger than those just below the cutoff. Overall, the policy improved access without reducing quality, yet its contribution to educational equality remains partial and uneven. The study offers new evidence on how quota allocation operates in county-level settings, providing useful insights for policymakers and educators in China seeking to reduce rural-urban disparities and strengthen the design of future quota reforms.

• Chaulagain, Ashmita; Widding-Havnerås, Tarjei; Elwert, Felix; Markussen, Simen; Lyhmann, Ingvild & Halmøy, Anne [Show all 8 contributors for this article] (2026). Effect of pharmacological treatment of attention–deficit hyperactivity disorder on contacts with child welfare services. British Journal of Psychiatry. ISSN 0007-1250. doi: 10.1192/bjp.2026.10554. Full text in Research Archive Show summary

  Background: Children and adolescents with attention–deficit hyperactivity disorder (ADHD) have a higher likelihood of contact with child welfare services (CWS). Evidence on whether pharmacological treatment of ADHD reduces such contact is limited. Aims: To estimate the causal effect of pharmacological treatment of ADHD on CWS contact. Method: In this quasi-experimental study, we used nationwide registry data covering all individuals aged 5–14 years and diagnosed with ADHD during 2009–2011 in Norway. We used linear probability models and instrument variable analyses to estimate the associations and causal effects of pharmacological treatment on CWS contact up to 4 years after diagnosis. As instrument variable analysis uses natural variation in treatment decisions between clinics as pseudo-randomisation, estimates inform effects for children and adolescents at the margin of treatment, i.e. patients whose treatment is more influenced by variation in treatment practice, e.g. due to less severe or atypical symptom presentation. Results: A total of 5930 children and adolescents aged 5–14 years were diagnosed with ADHD between 2009 and 2011 (mean (s.d.) age 10.1 (2.4) years; 4380 males (73.9%)). Instrument variable analyses showed a reducing effect of pharmacological treatment on the use of supportive interventions by 11.9 percentage points (95% CI: −20.12, −3.80) and out-of-home-placement by 3.30 percentage points (95% CI: −6.44, −0.15) at 2-year follow-up. This corresponds to the numbers needed to treat estimates of 8 and 30, respectively. Conclusions: Pharmacological treatment of ADHD reduces CWS contact among children and adolescents at the margin of treatment, lowering the probability of receiving supportive interventions and out-of-home placements. Findings suggest that medication reduces behavioural symptoms, which may improve the family coping mechanism and reduces the need for CWS involvement.

• Qin, Qi; Cheesman, Rosa Catherine Gillespie; Eilertsen, Espen Moen & Ystrom, Eivind (2026). Children's psychological traits and educational performance: How schools and residential areas moderate how individual traits translate into academic outcomes. JCPP Advances. p. 1–15. doi: 10.1002/jcv2.70100. Full text in Research Archive Show summary

  Abstract Background The extent to which children's psychological traits influence their educational performance is thought to depend on the fit between the individual and their developmental context. However, this assumption has yet to be empirically tested on a population scale. This study examines how neurodevelopmental, mental health, and personality traits interact with latent environmental contexts to enhance, maintain, or mitigate their educational performance. Methods Using the Norwegian Mother, Father and Child Cohort Study (MoBa), we estimated the association between 16 developmental traits and grade point average (GPA) in 26,875 children across environmental contexts in 2131 primary schools, 1075 middle schools, ~14,000 neighborhoods, 1471 districts, and 347 municipalities. Results Across the developmental traits, the effect on GPA ranged from −0.286 to 0.220. However, these effects varied substantially across environmental contexts (SD 0.022 to 0.090). Trait‐by‐context interactions were detected in primary schools (2 traits), middle schools (6 traits), neigbourhoods (0 traits), districts (3 traits), and municipalities (1 trait), respectively. Moderation magnitudes were largest for neurodevelopmental traits in primary schools. On average, the effects of ADHD and communication difficulties were −0.252 and −0.193. However, these effects differed substantially across primary schools with SD 0.090 and 0.070, implying b  < −0.370 and b  < −0.282 in 10% of schools. For average children, primary schools explained 0.504% of middle school GPA. Similarly, the effect of depression and extraversion was dependent on middle‐school environments ( b  = −0.128; SD = 0.058 and b  = 0.024; SD = 0.022). Moreover, schools and districts with high GPAs tended to express lower detrimental effects on children's developmental traits. Conclusion Schools and residential areas function as educational catalysts, enhancing or mitigating the influence of developmental traits. High‐performing environments compensate for psychological challenges, whereas lower‐performing contexts exacerbate difficulties. Because the study integrated multiple traits and contextual levels, the analyses were exploratory and data‐driven, and the findings should be interpreted as hypothesis‐generating. These results suggest a need for both context‐sensitive and individually tailored educational interventions.

• Göbel, Silke Melanie; Landerl, Karin & Lervåg, Arne Ola (2026). Longitudinal Predictors of Conceptual Understanding of Arithmetic Principles. Journal of Numerical Cognition. 12. doi: 10.5964/jnc.19523. Full text in Research Archive
• Zelihic, Dzan; Kyriakidou, Stefania; Ziaka, Laoura; McMurray, Bob & Protopapas, Athanassios (2026). Interference from adjacent words in visual word recognition. Journal of Memory and Language. ISSN 0749-596X. 149. doi: 10.1016/j.jml.2026.104761. Full text in Research Archive Show summary

  Recent findings show that lexical activation is slower when words are surrounded by other words, as they always are in natural reading. Here we focus on the proposal that this is due to direct interference from adjacent words that are processed in parallel. In three experiments using a flanked masked visual word adaptation of the visual world paradigm with adult skilled readers, we probed the spatial conditions for interference. Target words were flashed at fixation for 75 ms flanked by other words before being masked; we studied gaze shifts to the image (out of four displayed) corresponding to the target. We found that interference increases with proximity and is asymmetric (stronger from the right side). In the third experiment we included an image for one of the flanker words and we obtained direct evidence for lexical activation of the right-side flanker. Intriguingly, the strong asymmetry of lexical activation stands in contrast to a much weaker asymmetry in overall interference, indicating that different levels of representation are differentially involved in the online interactions among adjacent words. In all, we take our findings to constitute strong evidence for distributed attention around fixation differentially affecting diverse word processing stages, calling for a reconsideration of word recognition models that posit independent processing of individual words. The findings also suggest that the masked flanked visual word visual world paradigm is relevant for the study of attentional allocation during reading.

• Valstad, Mathias; Eilertsen, Espen Moen; Ayorech, Ziada; Cheesman, Rosa Catherine Gillespie; Demange, Perline Aline Delle & Eftedal, Nikolai Haahjem [Show all 8 contributors for this article] (2026). Indirect genetic effects of siblings. Journal of Child Psychology and Psychiatry. ISSN 0021-9630. doi: 10.1111/jcpp.70130. Full text in Research Archive Show summary

  Background Within-family designs are increasingly used to decompose genotype–trait associations into direct and indirect genetic effects. Many such designs, including trio designs or within-sibship designs, assume an absence of sibling indirect genetic effects. Methods We expand two well-known molecular genetic within-family designs, one variance component (genome-based restricted maximum likelihood) and one trait-based (structural equation modeling with polygenic indices), to estimate sibling indirect genetic effects, along with direct genetic effects. We link the Norwegian Mother, Father, and Child Cohort Study (MoBa) to Norway's national education database to model genetic effects on national standardized testing results at ages 10, 13, and 14, and on parent-rated attention-deficit hyperactivity disorder (ADHD) symptoms at ages 3 and 8 in up to 15,971 genotyped and phenotyped siblings. Results Estimates of direct and indirect genetic effects from the genome-based restricted maximum likelihood and the structural equation modeling with polygenic indices approaches converge, albeit with the variance component estimates typically an order of magnitude greater than the trait-based estimates. We observe no indirect genetic effects of siblings on educational performance at any age, and only slightly negative indirect genetic effects of siblings on ADHD symptoms at age 3. We argue that the latter effect might reflect parental contrasting ratings. Conclusions The results suggest that within-family models of educational performance are unlikely to be drastically biased by an assumption of absent sibling indirect genetic effects. Combining trait-based analyses with variance component analyses can benefit understanding of indirect genetic effects, especially when the effects are not specific to a particular mechanism.

• Valstad, Mathias; Eftedal, Nikolai Haahjem; Yang, Tianfang; Kvarstein, Elfrida Hartveit; Reichborn-Kjennerud, Ted & Ystrom, Eivind [Show all 7 contributors for this article] (2026). The epidemiology of personality disorders in Norway: a nationwide patient registry study. Social Psychiatry and Psychiatric Epidemiology. ISSN 0933-7954. doi: 10.1007/s00127-026-03083-7. Full text in Research Archive
• Eilertsen, Espen Moen; Eftedal, Nikolai Haahjem; Cheesman, Rosa Catherine Gillespie; Ayorech, Ziada; Ebeltoft, Joakim Coleman & Sunde, Hans Fredrik [Show all 9 contributors for this article] (2026). Multivariate maternal effects across the internalizing–externalizing spectrum in childhood: results from the Norwegian mother, father, and child cohort study. Journal of Child Psychology and Psychiatry. ISSN 0021-9630. p. 1–13. doi: 10.1111/jcpp.70111. Full text in Research Archive Show summary

  Background From a functionalist perspective, parenting behaviors have adaptive functions and are partly expressions of genetic variation. Maternal genes that have effects on children are often referred to as indirect maternal genetic effects. Indirect genetic effects provide a means for measuring the role of parenting without the need for specifying the relevant parental behaviors. We studied indirect maternal genetic effects to address both the importance and commonality of parenting across the internalizing–externalizing spectrum of behavior problems in childhood. We further addressed how indirect genetic effects impact our understanding of direct genetic effects if not accounted for. Methods Utilizing data from the Norwegian Mother, Father, and Child Cohort Study (MoBa), our analyses involved 42,423 children and their mothers. Both pedigree and genotype data were used to infer genetic relationships. We applied multivariate latent variable models to distinguish indirect maternal genetic effects and direct offspring genetic effects on seven measures of internalizing–externalizing behaviors. Results Our findings indicate significant maternal genetic influences, explaining 7%–18% of the variance across internalizing–externalizing behaviors. A general maternal effect common across behaviors could adequately account for most of the variability. The analyses further indicate that direct child genetic effects appear smaller and more complex when indirect maternal genetic effects are modeled simultaneously. Conclusions By summarizing the effects of parenting with indirect maternal genetic effects, we show a substantial contribution of parents with respect to internalizing–externalizing behaviors in childhood. Although parenting is multifaceted, the effects of parenting are general and can succinctly be described as a single common dimension. Further, our study demonstrates that direct genetic effects appear smaller and more complex when maternal genetic effects are accounted for, highlighting the confounding potential of parental effects in understanding the role of genetic differences in child psychopathology.

• Loui, Sofia & Protopapas, Athanassios (2026). Orthography and semantics in processing morphologically complex Greek words. Language, Cognition and Neuroscience. ISSN 2327-3798. doi: 10.1080/23273798.2026.2634796. Full text in Research Archive Show summary

  Previous studies have shown that the recognition of morphologically complex Greek nouns and verbs is facilitated by morphologically related primes, both derivational and inflectional, and at both early and late stages of processing. This raises the question of whether such facilitation reflects genuine morphological processing or merely similarity in form and/or meaning. To address this issue, we examined the effects of orthographic and semantic similarity on the processing of morphologically complex Greek words during visual word recognition. Using a primed lexical decision task with short and long stimulus onset asynchronies (SOAs), we found no facilitation by orthographically or semantically related primes at short SOA, whereas at long SOA, semantically related primes produced significant facilitation. These effects were smaller than previously reported morphological effects. Overall, the results suggest that morphological facilitation in Greek cannot be fully explained by orthographic or semantic overlap but reflects early, explicit morphological processing mechanisms.

• Koršňáková, Paulína; Qadri, Tahira Ali & Ye, Wangqiong (2026). The European sustainability competence framework (GreenComp) in light of TIMSS 2023 data. In Hastedt, Dirk; Koršňáková, Paulína & Ranđelović, Branislav M. (Ed.), Educating Pupils for Environmental Sustainability in Europe. Springer Nature Switzerland. ISSN 9783032147257. p. 53–86. doi: 10.1007/978-3-032-14725-7_3. Full text in Research Archive Show summary

  International large-scale assessments offer valuable opportunities to review educational outcomes from a sustainability competence perspective. This chapter builds on the conceptual overview of the European Commission’s GreenComp framework by examining how data from the Trends in International Mathematics and Science Study (TIMSS) 2023 context questionnaires relate to the four GreenComp competence areas. Latent class analysis is employed to classify grade four students into distinct profiles of sustainability engagement: Highly Engaged, Moderately Engaged, and Less Engaged. These profiles are interpreted in relation to the GreenComp framework and examined across TIMSS 2023 European education systems. Gender differences are also explored alongside analyses of the perceived roles of parents and teachers, confirming the significant part that both groups play in shaping students’ pro-environmental behaviors and sustainability engagement. Cross-national variation observed in the distribution of the profiles reveals how sustainability competences are shaped by diverse curricular, cultural, and socioeconomic factors. While TIMSS offers valuable entry points for examining sustainability engagement, limitations include item coverage, the cross-sectional nature of the data, and sample scope. The chapter concludes by underscoring the importance of integrating competence-based sustainability frameworks like GreenComp into future international assessments to enable more comprehensive and policy-relevant monitoring of sustainability competences.

• Severinsen, Yvonne; Ystrom, Eivind; Eftedal, Nikolai Haahjem; Nygaard, Egil; Bekkhus, Mona & Viana, Karine Porpino [Show all 9 contributors for this article] (2026). Determinants of Parental Emotion Socialization Behaviors: Insights From a Large‐Scale Population‐Based Family Study. Scandinavian Journal of Psychology. ISSN 0036-5564. 67(4), p. 953–971. doi: 10.1111/sjop.70082. Full text in Research Archive Show summary

  ABSTRACT Parental emotion socialization behaviors (ESBs) are essential for child development and are typically understood as influenced by factors related to three domains: the parent, the child, and the family context. However, it remains unclear how parents' childhood experiences with ESBs should be represented within these conceptual frameworks. Addressing the complexity of ESBs, the present study examined predictors across three theoretically derived domains and additionally included parents' recollected ESBs as a parent‐level factor. Questionnaire data were collected from a large population‐based cohort of Norwegian mothers and fathers ( n  = 4207; 2460 mothers) with children aged 3 to 13 years ( M  = 7.4 years). Supportive and non‐supportive ESBs were examined separately through hierarchical regression models incorporating parent, context, and child factors. The three domains collectively accounted for 28% of the variance in supportive ESBs and 29% in non‐supportive ESBs. The results clearly emphasized parental factors, with parent gender and recollected ESBs being the most influential predictors. Other parent factors, such as perceived parenting stress, alcohol use, and the personality traits agreeableness and openness, also showed unique effects across both types of ESBs. Among contextual factors, education, income, and country of birth predicted non‐supportive ESBs but not supportive ESBs. Child age and birth order were linked with supportive ESBs, whereas only child age predicted non‐supportive ESBs. Findings highlight the importance of parent characteristics, particularly gender and recollected emotion socialization from the family of origin, in predicting current parental ESBs beyond contextual and child‐related factors.

• Braak, Dieuwer Ten & Borgen, Nicolai Topstad (2026). How associations between executive function and early academic skills may have been missed: A quantile regression approach. Early Childhood Research Quarterly. ISSN 0885-2006. 75, p. 201–213. doi: 10.1016/j.ecresq.2025.12.009. Full text in Research Archive Show summary

  This study uses residualized quantile regression modeling to investigate how aspects of executive function (self-regulation and working memory) differentially predict mathematics, vocabulary, and phonological awareness for children with various levels of these skills. This approach addresses the limitations of traditional linear regression, which overlooks variations in associations at different points in the skill distribution. The study utilized longitudinal data from 243 children (Mage = 5.79, 49% female), assessed in kindergarten and first grade. Self-regulation was measured with the Head-Toes-Knees-Shoulders task, and working memory with the Digit Span. The quantile regression findings indicate rather stable associations between self-regulation/working memory and mathematics for children across the mathematics proficiency distribution, largely reflecting traditional linear coefficients. However, traditional linear regression misses out on important associations with vocabulary and phonological awareness. That is, working memory predicted vocabulary specifically at the low end of the distribution across kindergarten and first grade, while both working memory and self-regulation’s predictive power for phonological awareness shifted from the high end of the distribution in kindergarten to the low end in first grade. The study highlights the importance of considering that executive function’s involvement in academic skills may fluctuate depending on the specific aspect of executive function, the child's developmental stage, and the type of academic skill. Quantile regression provides a nuanced understanding of these relationships, revealing that traditional linear regression may miss critical information. The findings suggest that interventions targeting executive function may be specifically beneficial for children who struggle with language and literacy skills, particularly in first grade.

• Scherer, Ronny; Campos, Diego G.; Fütterer, Tim & Siddiq, Fazilat (2026). Unraveling gender disparities in teachers’ technological pedagogical and content knowledge: A large-scale meta-analytic review. Educational Research Review. ISSN 1747-938X. 50. doi: 10.1016/j.edurev.2026.100765. Full text in Research Archive Show summary

  This large-scale meta-analytic review investigates gender disparities in pre- and in-service K-12 teachers' Technological Pedagogical and Content Knowledge (TPACK) self-efficacy and performance. Synthesizing 915 effect sizes from 102 primary studies and 420 teacher samples (N = 681,745 teachers) in 70 countries via multilevel meta-analyses, we found small but significant gender differences favoring male teachers in TPACK self-efficacy (d = −0.17), particularly in technological knowledge (d = −0.31) and technological pedagogical knowledge (d = −0.14). However, no significant gender disparities were observed in TPACK performance (d = −0.08). Our findings revealed considerable heterogeneity in these effects across samples, studies, countries, measures, and over time, which could be partly explained by factors such as educational level, country-level gender inequality, and economic development. These results do not support male teachers’ advantage in all aspects of technology-related teaching competencies. Our meta-analytic review further implies that gender disparities in TPACK vary across contexts or over time.

• Ebeltoft, Joakim Coleman; Ystrøm, Eivind; Ayorech, Ziada & Eilertsen, Espen Moen (2026). Parental wealth and mental disorders in Norway (2006–2023): a nationwide registry-based study of 1.4 million young people. The Lancet Regional Health - Europe. 62. doi: 10.1016/j.lanepe.2025.101567. Full text in Research Archive Show summary

  Background Young people from families with low socioeconomic position have higher rates of mental disorders. However, wealth is underexamined despite large wealth inequity worldwide. Here, we aim to investigate the relationship between early life parental wealth and mental disorders in young Norwegians. Methods We conducted a population study of associations between early-life parental wealth and 17 diagnostic categories of mental disorders in 1.4 M children (7–12), adolescents (13–18), and young adults (19–24) observed 2006–2023. Ranked parental socioeconomic indicators at age 0–6 (wealth, income, occupation, and education) and mental disorder diagnoses (ICD-10 and ICPC-2) were obtained from Norwegian Tax, Employment, Education, and Control and Payment of Health Reimbursements registries. Estimates were derived from mean prevalences, generalised estimating equations, and sibling comparison designs. Findings Parental wealth represents a gradient in young people’s mental disorders across age, sex, diagnostic categories, and cohorts. The lowest wealth quintile demonstrated 87% [95% CI = 78–96%] higher 1-year prevalence than the highest quintile. In multivariable analyses, parental wealth was the strongest predictor of mental disorders relative risk in adolescents (1.83 [1.76–1.9]) and young adults (1.92 [1.8–2.04]), while wealth (1.53 [1.46–1.6]) and education (1.52 [1.45–1.6]) were the strongest predictors in children. Parental wealth has a significant within-family association with mental disorders (relative risks: children 1.57 [1.44–1.71], adolescents 1.34 [1.26–1.42], young adults 1.42 [1.31–1.54]). Interpretation Our study serves as a point of reference for understanding the relationship between parental wealth and mental health. Our findings establish early life parental wealth as a fundamental social gradient in young people’s mental disorders.

• Zhang, Lu & Andersson, Björn (2026). Likelihood ratio tests with marginal maximum likelihood using Laplace approximations and adaptive quadrature. Journal of Statistical Computation and Simulation. ISSN 0094-9655. p. 1–26. doi: 10.1080/00949655.2026.2616410. Full text in Research Archive Show summary

  Estimation of generalized linear latent variable models is typically done with marginal maximum likelihood (MML) estimation which requires approximation methods to compute integrals without a closed form solution. In applied settings, likelihood ratio tests are often used to test hypotheses regarding parameter restrictions. This study examines the properties of likelihood ratio tests when using approximate MML estimation. We consider first- and second-order Laplace approximations, along with adaptive Gauss-Hermite quadrature with varying numbers of quadrature points. In two simulation studies we perform likelihood ratio tests, varying data types (binary, ordinal, and count data), sample sizes, and the number of observed variables. The first simulation examines slope parameter equivalence, while the second focuses on group restrictions in multiple group models. Results indicate adaptive quadrature and second-order Laplace approximations provide reliable inference across most settings. Meanwhile, the first-order Laplace approximation generally works well except in some binary data cases.

• Chegeni, Razieh; Nes, Ragnhild Bang; Cheesman, Rosa Catherine Gillespie; Ayorech, Ziada Ng'ombo Laurel; Ystrøm, Eivind & Røysamb, Espen (2026). Parental direct and indirect genetic effects on offsprings’ internalizing problems across development. Nature Mental Health. doi: https:/www.researchsquare.com/article/rs-6862539/v1. Full text in Research Archive Show summary

  Internalizing problems are common in youth and linked to adverse long-term outcomes. While both children’s own genetic variants (direct genetic effects) and the genetics of their parents (indirect genetic effects) contribute, the direct and indirect genetic traits involved remain unclear. Here, w...

• Brodeur, Abel; Borgen, Nicolai T.; Borgen, Solveig Topstad; Gugushvili, Alexi; Emirmahmutoglu, Aysil & Gavrilova-Zoutman, Evelina [Show all 7 contributors for this article] (2026). Comparing Human-Only, AI-Assisted, and AI-Led Teams on Assessing Research Reproducibility in Quantitative Social Science. Proceedings of the National Academy of Sciences of the United States of America (PNAS). ISSN 0027-8424. 123(22). doi: 10.1073/pnas.2524747123. Full text in Research Archive Show summary

  Large Language Models (LLMs) such as ChatGPT are transforming how scientists conduct and validate research, offering promise as tools to improve scientific reproducibility. However, computational reproducibility and error detection remain expensive and labor-intensive. We experimentally test how collaboration between researchers and LLM assistants influences the reproduction of quantitative social science findings across different levels of AI autonomy. We randomly assigned 288 researchers to 103 teams working under three conditions: human-only, AI-assisted (using ChatGPT as a collaborative tool), or AI-led (ChatGPT operating with minimal human oversight). Teams reproduced published results from leading social science journals, detected coding errors, and proposed robustness checks. Human-only and AI-assisted teams achieved comparable reproduction rates (94% vs. 91%) and performed similarly on most outcomes, except human-only teams identified significantly more major coding errors. Both substantially outperformed AI-led teams, which achieved only a 37% reproduction rate, detected fewer errors across all categories, proposed weaker robustness checks, and required more time. This autonomous approach, however, likely represents only a lower bound of AI capabilities. Despite rapid model advances, expert human judgment currently remains indispensable for reliable empirical verification. While AI assistance did not degrade most outcomes, it provided no measurable advantages and was associated with reduced detection of major errors. However, the 37% autonomous reproduction rate indicates that AI could provide value in settings where scale or cost constraints preclude human review of papers, even though general-purpose LLMs offer no immediate advantages for human-supervised verification.

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• Smajlagic, Dinka; Sunde, Hans Fredrik; Valenza-Troubat, Noemie; Kelly, Kristen; Lyu, Xuanyu & Sapin, Emmanuel [Show all 12 contributors for this article] (2026). Estimating assortative mating using haplotype-specific polygenic scores across physiological, psychological, and social traits in the Norwegian MoBa Cohort. doi: https:/s3.amazonaws.com/ClubExpressClubFiles/971921/documents/BGA_2026_Final_Program_1883376854.pdf?AWSAccessKeyId=AKIA6MYUE6DNCQ7GISON&Expires=1790839847&response-content-disposition=inline%3B%20filename%3DBGA_2026_Final_Program.pdf&Signature=nfauyWIWzAanx8Du1HeYli1Hi0Q%3D. Full text in Research Archive
• Madhavan, Vaishnavi K; Demange, Perline Aline Delle; Ayorech, Ziada; Hottenga, Jouke Jan; Bartels, Meike & Ystrom, Eivind [Show all 8 contributors for this article] (2026). Bipolar Disorder and Education: Deciphering a Complex Relationship using Genetic and Sibling Differences. doi: https:/s3.amazonaws.com/ClubExpressClubFiles/971921/documents/BGA_2026_Final_Program_1883376854.pdf?AWSAccessKeyId=AKIA6MYUE6DNCQ7GISON&Expires=1790839847&response-content-disposition=inline%3B%20filename%3DBGA_2026_Final_Program.pdf&Signature=nfauyWIWzAanx8Du1HeYli1Hi0Q%3D. Full text in Research Archive
• Melby-Lervåg, Monica; Hagen, Åste Mjelve; Lervåg, Arne & Rogde, Kristin (2026). Tidlig innsats er ikke nok: Effekten av språkstimulering i barnehage er av begrenset varighet. [Journal]. FORSKNING.NO. Full text in Research Archive
• Ystrom, Eivind & Torvik, Fartein Ask (2026). How to study GxE in schools. Full text in Research Archive
• Ystrom, Eivind; Demange, Perline Aline Delle; Cheesman, Rosa Catherine Gillespie; McAdams, Thomas Andrew; Eilertsen, Espen Moen & Timpe, Clara Marie Fides [Show all 8 contributors for this article] (2026). Child Personality Polygenic Indices and Parental Distress: Evidence of Active Gene-Environment Correlations and Interactions from Parent–Offspring Trios. doi: https:/osf.io/fwaqp/overview. Full text in Research Archive Show summary

  Child temperament and personality are conjectured to affect parental distress, and there are findings supporting such transactions. Yet, to date, there is no evidence for such evocative gene-environment correlations using exogenous within-family offspring genetic variation. Using 30 000 parent–offspring genotyped trios from the Norwegian Mother, Father and Child Cohort (MoBa), we test how child personality polygenic indexes (PGIs) independently affect maternal and paternal mental distress across the life course (age 16-60). The second longstanding hypothesis is that such child-to-parent transactions are non-additive due to gene-environment interactions. We will reveal the scope of this by estimating the expansion of within-person-timepoint parental mental distress over child personality PGIs. The third longstanding hypothesis is that the evocative effect is dependent on the parental personality, or the “goodness-of-fit”. We will examine moderation by parental Big Five PGIs to test if the effect of a child’s personality on parent depression depends on the parent’s own personality predispositions. This genetically controlled approach provides a novel and robust test of child- evoked effects across the life course. Results for both mothers and fathers will be presented, highlighting the power of child PGIs as a new tool to reveal intergenerational influences on parental mental distress.

• Ystrom, Eivind (2026). Disentangling Direct and Indirect Genetic Effects on Complex Traits: Insights from Two Large-Scale Family Studies. doi: https:/bga.org/docs.ashx?id=1781704. Full text in Research Archive
• Ystrom, Eivind; Ayorech, Ziada; Bjørndal, Ludvig Daae; Timpe, Clara Marie Fides; Cheesman, Rosa Catherine Gillespie & Eilertsen, Espen Moen [Show all 8 contributors for this article] (2026). Child Personality Polygenic Indices and Parental Distress: Evidence of Active Gene- Environment Correlations and Interactions from Parent–Offspring Trios. doi: https:/bga.org/docs.ashx?id=1781704. Full text in Research Archive
• Ystrom, Eivind (2026). Da Mette og Helle ble gravide, ble de en snakkis blant helsepersonell. [Journal]. Aftenposten. Full text in Research Archive Show summary

  Dette er helt tilfeldig og ganske usannsynlig. Men de eneggede tvillingene Mette og Helle Bugge Bergsund (36) har selv fått hvert sitt par eneggede tvillinger i løpet av tre måneder.

• Ystrom, Eivind (2026). Are You Mostly Noise? Eivind Ystrøm on the Genetics of Personality. doi: https:/www.podbean.com/ew/pb-x24tj-1a9abb6. Full text in Research Archive Show summary

  Personality psychologists were doing behavior genetics way before it was cool. In this episode, Rafael and Aysu sit down with Eivind Ystrøm, personality psychologist at the University of Oslo, to talk about what personality actually is, how heritable it turns out to be, and why the field was so far ahead of the rest of the social sciences in taking genetics seriously. They also dig into one of the most provocative findings in the field: the so-called "gloomy prospect" — the idea that a large chunk of what makes you you may come down to essentially random, non-systematic events that even siblings growing up in the same household don't share. What does this mean for the search for specific environmental causes of personality? And more importantly — what is the mysterious mutation that Eivind thinks he may have?

• Ystrom, Eivind & Ivanova, Anna (2026). Do reproductive factors shape depression stability? Early menarche, endometriosis and PMS in longitudinal registry data. doi: https:/2026.ehps.net/wp-content/uploads/2026/08/ehps26_final_program_27_08-1.pdf. Full text in Research Archive Show summary

  Background: Menstrual and gynaecological conditions may increase depression risk, but it is unclear whether they relate to onset versus persistence. Methods: 85,637 women aged 14 to 72 from the Norwegian Mother, Father and Child Cohort Study (MoBa) contributed with 18,415,809 person-months of patient registry data (2006–2023) on primary-care depression diagnosis. Early menarche (before age 12), endometriosis, and Premenstrual Syndrome (PMS) was recorded by questionnaire. Log-binomial regression was used to estimate risk ratios (RR) for population average effects and conditioned on prior-month depression to additionally test condition*prior-depression (stability) interactions and condition*age interactions. Results: Depression was prevalent in 26.3% of women across the 18-year observation period and incident within 1.18% of the person-months. Early menarche, endometriosis, and PMS predicted higher depression risk RR=1.22 (95%CI 1.15-1.29), 1.19 (95%CI 1.04-1.36), and 1.68 (95%CI 1.61-1.75). Conditioning on prior month depression status, main effects were for early menarche RR=1.21 (95%CI 1.15-1.28), endometriosis RR=1.19 (95%CI 1.04-1.35), and PMS remained RR=1.70 (95%CI 1.63-1.77); indicating associations were primarily with transitions into depression rather than persistence. Early menarche RR=0.83 (95%CI 0.79-0.88), endometriosis RR=0.83 (95%CI 0.72-0.95), and PMS RR=0.59 (95%CI 0.56-0.61) all contributed to lower stability of depression. Furthermore, early menarche gave a diminishing risk for depression with older age. Conclusions: Early menarche, endometriosis, and PMS mark elevated depression burden. However, this appears to happen primarily through increased transitions into depression rather than chronicity. Hence, early age of menarche, endometriosis, and PMS may help identify women eligible for preventive mental health interventions rather than being fixed markers of life-course depression risk.

• Ystrom, Eivind (2026). No Link Between Acetaminophen in Pregnancy and Autism, a Study Finds. [Journal]. The New York Times. doi: https:/www.nytimes.com/2026/01/16/health/tylenol-autism-acetaminophen-study.html. Full text in Research Archive Show summary

  The review looked at more than three dozen studies and found no evidence that acetaminophen increased the risk of neurodevelopmental disorders in children.

• Ystrom, Eivind & Madsen, Ole Jacob (2026). Fritt hjemme, strengt på skolen. [Internet]. forskning.no. Full text in Research Archive Show summary

  Dagens foreldre skaper problemer på skolen, ifølge lærere. Professor mener vi overdriver effekten av foreldrestiler.

• Ystrom, Eivind (2026). Ny studie tilbakeviser Trumps Paracet-teori. [Internet]. tv2. Full text in Research Archive Show summary

  USAs president påstod at risikoen for utvikling av autisme økte ved mors inntak av paracetamol.

• Chen, Jianan & Braeken, Johan (2026). Traditional Progressive Tests with Stopping Rules from Computerized Adaptive Testing: Do Potential Advantages Outweigh Added Complexity? Full text in Research Archive
• Rønneberg, Vibeke; Amland, Tonje; Solheim, Oddny Judith; Lervåg, Arne; Melby-Lervåg, Monica & Ertesvåg, Sigrun K. [Show all 7 contributors for this article] (2026). Improving Reading And Mathematical Skills Through an Integrated Intervention: A Multi-site Randomized Trial. doi: https:/www.the-mcls.org/conferences/mcls-2026-padua. Full text in Research Archive
• Lervåg, Arne; Wang, Lei & Melby-Lervåg, Monica (2026). Developmental Dynamics between Reading Comprehension, Word Reading and Vocabulary in Norwegian Second to Third Graders. Full text in Research Archive Show summary

  Purpose — It is well established that language skills, such as vocabulary, are important precursors for word reading and reading comprehension. However, theories about reading development are not very specific about how different components impact reading during various developmental phases. This study examines the developmental relationship between reading comprehension, vocabulary, and word reading skills in an early phase of reading. Models, which separate variation within and between the children, and those that do not, are used. Method — 288 children, recruited 4 months after the start of formal reading instruction, were measured four times over 1.5 years. Different cross-lagged panel models were estimated to test the direction of influence between the development of reading comprehension, vocabulary skills, and word reading skills. Results — Models, separating within-person from between-person variation, clearly showed that changes in word-reading skills were associated with later reading comprehension skills. This was less clear in the models that mix up the within-person and between-person variation. Some, but fewer, dynamic relations were found for vocabulary and reading comprehension, and the ones found were in models that mix up the within-person and between-person variance. Conclusions — The findings provide important information about the developmental dynamics of reading in a relatively early phase of development. Further, the results inform us about the importance of choosing the appropriate model if we are interested in how a child’s reading skills develop over time.

• Donolato, Enrica; Wahl, Hedda Novang; Melby-Lervåg, Monica & Lervåg, Arne (2026). Math anxiety and math skills development in children: a longitudinal study on early predictors. Full text in Research Archive Show summary

  Introduction. Math anxiety and math skills are closely intertwined, yet their early predictors in childhood remain poorly understood. Previous research has identified cognitive and affective predictors of math performance, including intelligence and working memory (Amland et al., 2025), knowledge of mathematical symbols (Szczygieł et al., 2024), and general and math anxiety (Barroso et al., 2021; Caviola et al., 2022). Similarly, there is evidence that math anxiety is shaped by general anxiety (Szczygieł et al., 2024; Wang et al., 2014), working memory (Pellizzoni et al., 2022), and knowledge of mathematical symbols (Szczygieł et al., 2024). Despite extensive correlational evidence, few longitudinal studies have systematically examined cognitive and affective predictors of math anxiety and math skills in school-age children. Research Aims. The goal of this study is to examine children’s math anxiety and math skills development and identify their cognitive and affective predictors in a sample of children followed up from kindergarten to primary school. Materials and Methods. The sample consisted of 259 children (52% boys; M age = 5.5 years at project onset). At the first time point, during their final year of preschool, children completed assessments of cognitive abilities, numeracy skills, and general anxiety. From Grade 3 to Grade 6, children were assessed annually on math anxiety (Achievement Emotions Questionnaire–Math Anxiety; AEQ-MA), arithmetic fluency (Test of Basic Arithmetic and Numeracy Skills; TOBANS) and a mathematical reasoning (Word Problems subtest of the WISC-IV). Assessments were administrated individually in sessions of approximately 60 minutes during kindergarten or school hours. Results. Growth models are being used to examine math anxiety and math skills and to test early predictors of individual differences in growth. Final results from ongoing analyses will clarify the extent to which early cognitive, numeracy and affective factors contribute to changes in math anxiety and math skills in primary school. Discussion. These findings are expected to contribute to a better understanding of early factors that may place children at risk for unfavourable trajectories in developing math anxiety or poor math skills. The study has implications for early identification, highlighting how targeting foundational skills may support both math skills and mitigate math anxiety. Findings will further inform how these insights can be translated into educational practices to enhance young students’ successful math learning.

• Lervåg, Arne; Wahl, Hedda Novang; Donolato, Enrica & Melby-Lervåg, Monica (2026). The developmental dynamics between math anxiety and math skills: examining three theories. Full text in Research Archive Show summary

  Introduction. Math anxiety is consistently associated with poorer learning and achievement, yet the direction of this relationship remains debated (e.g., Namkung et al., 2019). Three primary theoretical models explain the link between anxiety and achievement. The reduced competency model suggests that weak math skills generate anxiety. The learning avoidance model proposes that anxiety leads students to disengage from practice and participation, thereby harming performance. The reciprocal model integrates both processes, proposing a cyclical relationship in which poor skills increase anxiety, which in turn further impairs achievement (Carey et al., 2016). Some studies using traditional cross-lagged panel models support reciprocal effects (Gunderson et al., 2018). However, newer Random Intercept-Cross-Lagged Panel Models (RI-CLPMs) control for stable individual differences, allowing clearer examination of within-person changes over time (Hammaker et al., 2015). One five-year study applying RI-CLPMs found that anxiety negatively predicted later math grades within individuals, whereas grades did not predict anxiety. Thus, whereas traditional CLPM findings favor the reciprocal model, RI-CLPM results align more closely with the learning avoidance model. However, this study relied on grades rather than standardized tests, and anxiety was not assessed specifically in testing contexts. Research Aims. The present study uses RI-CLPMs to examine whether developmental relations between math anxiety and achievement vary across anxiety types, providing a more nuanced understanding of how emotions influence children’s mathematical learning. Norwegian students were followed from Grade 3 to Grade 6, with two different measures of anxiety, class anxiety and test anxiety. Methods. Two hundred and fifty children's math anxiety and math word problem skills were tested annually over three years. Results. The results show that earlier higher levels of test anxiety were significantly related to poorer later math skills. For class anxiety, there was a significant relation in the opposite direction. Poor math skills were related to later math class anxiety. In this model, there was also some evidence of a relationship in the opposite direction, but sensitivity tests suggest this might be due to confounders. Further analyses also revealed that the effect of poor math skills on class anxiety was moderated by gender, with higher effect sizes for girls than for boys. Discussion. Support was found for all the above-mentioned three theories of this relationship, but the results suggest types of anxiety and gender might moderate the direction and strength of the relations between anxiety and math skills.

• Mangset, Marte; Olsen, Oskar Grannæs & Staven, Helle Dyrendahl (2026). Symbolic victory, material constraint. Full text in Research Archive
• Qin, Qi; Demange, Perline Aline Delle; Eilertsen, Espen Moen; Cheesman, Rosa Catherine Gillespie & Ystrom, Eivind (2026). How Schools and Neighborhoods Shape the Translation of Polygenic Personality Indices into Academic Outcomes. Full text in Research Archive Show summary

  The Big Five personality traits are robust predictors of individual differences in academic outcomes, yet the mechanisms through which they shape the outcomes remain unclear. Building on our prior work showing contextual moderation of non-cognitive polygenic indices (PGI), we hypothesize that personality traits likewise do not exert uniform influences across contexts. Instead, their effects on academic outcomes emerge through dynamic interactions with the social and economic environments in which individuals develop. Recent GWAS on Big Five personality traits enable the construction of PGIs that quantify the individual-level genetic propensities, and are largely independent of the environment and minimize reverse causality. Using data from ~32,000 trios in the Norwegian Mother, Father, and Child Cohort Study (MoBa) linked to national school and residential registries, we apply multilevel models to investigate how personality-related PGIs contribute to students’ grade point average (GPA), and how these associations vary across latent school and neighborhood contexts. We further test the extent to which the measured socioeconomic status aggregates at the school and neighborhood level interact with individual liability in personality traits. This work aims to provide a comprehensive framework for understanding how individual propensities for personality become developmentally expressed into academic outcomes within real-world contextual ecologies.

• Peng, Qiyuan; Rietveld, Cornelius A.; Ystrom, Eivind; Zachrisson, Henrik Daae; Havdahl, Alexandra & Cheesman, Rosa Catherine Gillespie (2026). Does Universal Childcare Affect Early Child Development? Full text in Research Archive
• Fang, Yuan; Ystrom, Eivind; Eftedal, Nikolai Haahjem; Edvoll, Maud Clemson; Folstad, Siri Hausland & Røysamb, Espen [Show all 10 contributors for this article] (2026). Socioeconomic Differences in Student Mental Health Following a Nationwide Curriculum Reform. Full text in Research Archive
• Torkildsen, Janne von Koss; Hagelund, Silje & Knoph, Rebecca (2026). What Does My Reader Need? Demonstrations of Audience Awareness in Sixth-Graders’ Written LEGO Instructions. Full text in Research Archive
• Torkildsen, Janne von Koss; Hagelund, Silje; Knoph, Rebecca; Jerijærvi, Camilla Bøen & Lervåg, Arne (2026). Gender differences in self-reported audience awareness in middle schoolers’ argumentative writing. Full text in Research Archive
• Knoph, Rebecca; Lawrence, Joshua; Kulesz, Paulina & Francis, David (2026). Task, learner, and word: A tripartite view of vocabulary assessment outcomes. Full text in Research Archive Show summary

  Purpose This study examines how vocabulary task format, learner proficiency, and lexical characteristics jointly influence assessment performance. While test development often assumes that the format of a vocabulary measure does not affect what is measured, we challenge this assumption by investigating whether synonym and definition identification tasks show different results for knowing a word, particularly for students at different levels of language proficiency. Method Over 6,000 linguistically diverse middle school students from an urban California district completed 50 synonym items and a randomly assigned 12-item definition form, with 20 target words overlapping across formats. Explanatory item response theory (EIRT) models extended random intercept models to include person-level predictors (ELL classification, grade, gifted participation, socioeconomic status, reading comprehension) and item-level predictors (task type, frequency, complexity, proximity, polysemy, diversity). These models estimated main and interaction effects, capturing variability in both student ability and item difficulty across tasks and proficiency levels. Results Students were generally more accurate on synonym than definition items, but this advantage disappeared for Limited English Proficient (LEP) learners. Words with many meanings and broad contextual use were easier, especially on synonym tasks, suggesting that flexible meaning representations aid identifying semantic relationships. Conclusions Vocabulary task format interacts systematically with both learner proficiency and lexical features, indicating that assessment outcomes depend on how knowledge is elicited and for whom. The findings challenge linear conceptions of vocabulary “depth” and highlight the importance of designing and interpreting vocabulary measures that account for task effects and learner diversity.

• Knoph, Rebecca; Hagelund, Silje & Torkildsen, Janne von Koss (2026). What Does My Reader Need? Audience Awareness in SixthGraders’ Written LEGO Instructions. Full text in Research Archive Show summary

  Purpose: Audience awareness is central to effective writing, requiring writers to anticipate readers’ needs and misunderstandings (Bereiter & Scardamalia, 1987; Hayes, 2012). Failures to support and consider readers have contributed to catastrophic consequences, including fatal radiation explosions linked to technical instructions that failed to anticipate user interpretation (Leveson & Turner, 1993). This study examines how Norwegian sixth-grade students demonstrate audience awareness through reader supports when writing LEGO-based procedural texts for real readers (though low-stakes), and whether these demonstrations differ by writer gender.Method: Seventy sixth-grade students wrote instructions for a specific peer to build a six-piece LEGO figure using only the written instructions, ensuring genuine communication. Three researchers independently coded texts for reader supports indicating audience awareness using a deductively-developed, inductively-refined rubric with seven categories: reader connection, adaptation, emphasis, sequential markers, figurative language, goals, and action support. Patterns of reader support use were compared by author gender using frequency counts and qualitative ex‐ amples.Results: Sixth-grade writers demonstrated audience awareness in procedural writing. Sequence markers were almost always present, and action support appeared in over half of essays, whereas reader-oriented supports (e.g., reader connection and goal orientation) appeared in only about one third. Girls produced substan‐ tially more reader supports than boys, with more than four times as many reader connection instances and twice as many adaptation, action support, and goal orientation instances. Discussion: Authentic, hands-on writing tasks can elicit clear demonstrations of audience awareness through reader supports, even in relatively short procedur‐ al texts (approximately 100 words). Despite the task being designed to align with boys’ LEGO-building interests and spatial reasoning strengths, girls more consistently and flexibly supported their readers. These findings suggest gender differences in how young writers conceptualize and enact audience awareness, underscoring the need for instructional approaches that explicitly support students in anticipating and responding to readers’ needs.

• Knoph, Rebecca; Hagelund, Silje & Torkildsen, Janne von Koss (2026). Writing Quality on a LEGO-Based Procedural Writing Task: Gender Differences in Analytic Traits. Full text in Research Archive Show summary

  INTRODUCTION: Young writers demonstrate substantial potential for composing texts, and measures of cognit‐ ive capacity related to writing show no gender differences (Bourke & Adams, 2012). Despite this, boys often report lower motivation for school-based writing and greater difficulty with transcription and text production (Olinghouse, 2008), and girls consistently outperform boys on writing assessments (Kim, 2017). These differ‐ ences may be partly genre- and topic-related, as girls more often prefer narrative texts and boys factual or expository materials (McGeown, 2016). This study therefore examined gender differences in writing quality on a hands-on procedural task designed to broaden engagement and explicitly specify audience and pur‐ pose.METHODS: Seventy Norwegian sixth-grade students viewed an image of a six-piece LEGO figure and wrote instructions so a peer could rebuild the figure without the image. Texts were then rated using the six subdimensions of the 6+1 Traits framework (Culham, 2003).RESULTS: Girls outperformed boys on all dimen‐ sions except Word Choice, with the most robust gender difference observed for Voice (Hedges’ g=0.83). Smaller but underpowered gender differences were observed for remaining traits (0.15-0.48). All subscores were strongly correlated with total score (rs=.67-.94), and the correlational structure was equivalent between genders. Girls produced longer texts than boys (d = 0.48), and word count was moderately related to writing quality (rs=.38-.64). Adjusting for word count partially attenuated gender differences (38-71%), though controlling for word count may remove substantively meaningful variance, as word count likely reflects underlying differences in fluency and task engagement.CONCLUSIONS: Overall, gender differences in writing persisted even on the hands-on task de‐ signed to broaden engagement. Specifically, girls continued to outperform boys in expressive voice even after adjusting for word count, suggesting that while engaging task design is important, it may be insufficient to reduce gender differences in writing quality and potentially a focus on expressive voice for instruction, particularly for boys.

• Hagelund, Silje; Torkildsen, Janne von Koss & Lervåg, Arne (2026). Perspective-taking and writing motivation on writing quality. Full text in Research Archive Show summary

  A conference presentation about our study, where we examine whether writing motivation and perspective-taking correlate with 7th grade argumentative writing quality after accounting for foundational language skills. Specifically, we investigate how self-reported perspective-taking and writing motivation relate to three dimensions of argumentative writing: writing conventions (WC), language complexity (LC), and argumentative skills and audience awareness (AAW) when we account for oral language (vocabulary, listening comprehension), reading-related skills (reading comprehension, word decoding), and transcriptional skills (spelling, transcription).

• Hagelund, Silje; Torkildsen, Janne von Koss & Lervåg, Arne (2026). Can perspective-taking and writing motivation predict argumentative writing skills beyond reading comprehension and decoding in 7th-grade students? Full text in Research Archive Show summary

  A conference poster with results from our study examining how writing motivation and perspective-taking correlate with aspects of argumentative writing quality in 7th grade after accounting for foundational language skills.

• Ziaka, Laoura; Adedeji, Victoria; Altani, Angeliki; Papadaki, Stella; Simonsen, Kristin & Zelihic, Dzan [Show all 7 contributors for this article] (2026). Eye-voice span in serial naming tasks: material load and the maturity of cognitive control. doi: 10.13140/RG.2.2.24776.28163. Full text in Research Archive Show summary

  Studies examining eye-voice span (EVS) in serial naming (SN) tasks with and without internal interference (incongruent and neutral conditions of the multi-item Stroop task) show dynamic changes in EVS as a function of time-on-task (item position), interpreted as a shift from more parallel to more serial processing due to nearby-items interference and cognitive overload. However, little is known about how the maturity of the control system may influence these dynamics. Here, we examine within-task changes in spatial and temporal EVSs in 197 2nd- and 5th-graders across SN tasks varying in load (digits, objects, and words) at three timepoints. Audio recordings were first processed automatically, then manually to correct the marked speech onsets and offsets and to annotate errors. Gaze data were processed using custom scripts to assign fixations to items. EVS measures were calculated on time-aligned audio and gaze data: Spatial EVSs capture item distance between gaze and voice at articulation onset and offset, while temporal EVSs capture time differences between fixation and articulation instants. We fit generalized additive mixed-effects models to examine whether EVSs change as a function of time-on-task, material load, and assessment timepoint (item position × task × time interaction) and if the changes differ between grades.

• Diamanti, Vassiliki; Altani, Angeliki; Simonsen, Kristin; Zelihic, Dzan & Protopapas, Athanassios (2026). Where do the effects of repeated reading come from? Full text in Research Archive Show summary

  Purpose. Repeated reading is a frequently chosen intervention method for increasing reading fluency, with documented effectiveness. Yet the mechanisms underlying its effects remain unknown. Does it work by primarily affecting recognition of the specific words repeatedly encountered, or by enhancing more general cognitive processing mechanisms underlying reading efficiency across words? Or both? Method. We administered a brief one-on-one intervention to Norwegian children attending Grades 2 (N=78) and 5 (N=92) in an AB/ΒΑ crossover design with three testing points around two 6-week intervention periods. In each of 24 sessions, children read aloud an age-appropriate passage four times, following modeling. Passages were story “chapters” of approx. 80 words each for G2 and 200 for G5. The primary outcome was oral reading fluency (ORF, correct words per minute) in near-transfer passages (containing selected words from the intervention). We also tested ORF in far-transfer passages (from a standardized test), word and pseudoword list reading efficiency, reading comprehension accuracy and efficiency, and serial and discrete naming and (unrelated) word reading. Results. Significant effects of the intervention were only obtained for ORF in near transfer passages (approximately 10% increased WPM). We also observed a significant decrease in reading latency for individual words encountered during the intervention. None of the other measures exhibited significant intervention effects. Conclusions. The earliest and largest effects of repeated reading intervention, across grades, appear to concern familiarization with the specific words that are repeatedly read. This finding has implications for the selection of intervention content aiming to maximize utility in educational and clinical settings.

• Protopapas, Athanassios; Ziaka, Laoura; Zelihic, Dzan; Simonsen, Kristin; Altani, Angeliki & McMurray, Bob (2026). Children’s visual word recognition is hampered by adjacent stimuli. Full text in Research Archive Show summary

  Purpose. Skilled readers preview upcoming words before fixating them. Developing readers are limited in using parafoveal information, leading to the expectation that they are insensitive to adjacent stimuli. However, lack of benefit from nearby items does not preclude a negative impact on recognition processes. Given recent findings of interference from adjacent words for adult readers, we investigated whether children’s word recognition is also affected. Method. We tested Norwegian children attending Grades 2 (N=62) and 5 (N=141) using a modified version of the visual world paradigm with masked flanked visual word targets. Four images were displayed at the screen quadrants. A target word was briefly flashed (G2: 450 ms; G5: 250 ms) centrally, either in isolation or flanked by strings of repeated symbols, unknown fonts, or other words, followed by a mask. Children had to click on the picture matching the target. The latency of the gaze shift to the target image indexes lexical activation. Results. Compared to the baseline condition with no flankers, flanking words or unfamiliar-font strings interfered with lexical activation of the foveated target word. Strings of repeated symbols had no effect. The results were similar for the two grades, except that the most advanced readers exhibited reduced frequency effects with word flankers. Conclusions. Adjacent stimuli are to some extent simultaneously processed along with the foveated word and strongly interfere with it, from the earliest stages of—and throughout—reading development. We propose that management of interference from adjacent words is a major factor modulating the development and expression of reading skill.

• Vartun, Marika (2026). Barn med svakt ordforråd kan løftes med enkle grep. Forskning.no. ISSN 1891-635X. doi: https:/www.forskning.no/barn-og-ungdom-partner-pedagogikk/barn-med-svakt-ordforrad-kan-loftes-med-enkle-grep/2674373. Full text in Research Archive Show summary

  Elever som går i småskolen, men har et ordforråd som et barnehagebarn, vil streve i skole og dagligliv.

• Vartun, Marika (2026). To elever med samme karaktergjennomsnitt er ikke nødvendigvis like faglig sterke. Forskning.no. ISSN 1891-635X. doi: https:/www.forskning.no/elever-partner-pedagogiske-fag/to-elever-med-samme-karaktergjennomsnitt-er-ikke-nodvendigvis-like-faglig-sterke/2675805. Full text in Research Archive Show summary

  Ny forskning viser at noen valgfag er mye vanskeligere å få gode karakterer i enn andre.

• Vartun, Marika & Bjermeland, Monica (2026). Utdanning lønner seg. Forskning.no. ISSN 1891-635X. doi: https:/www.forskning.no/partner-penger-og-privatokonomi-sosiologi/utdanning-lonner-seg/2665767. Full text in Research Archive Show summary

  Et år ekstra utdanning er en god investering, viser studie.

• Vartun, Marika & Bjermeland, Monica (2026). Tidlig innsats er ikke nok: Effekten av språkstimulering i barnehage er av begrenset varighet - Forskningsnytt. www.forskning.no. doi: https:/www.uio.no/forskning/forskningsnytt/artikler/2026/tidlig-innsats-er-ikke-nok-effekten-av-sprakstimulering-er-av-begrenset-varighet.html. Full text in Research Archive Show summary

  – Om vi mener alvor med å styrke barns språk og leseutvikling, holder det ikke med intensiv språkstimulering i barnehagen. Vi trenger langvarig og målrettet støtte både i barnehage og skole, sier forsker.

• Zhang, Lu; Skov, Henrik; Massling, Andreas; Dall’Osto, Manuel; Evangeliou, Nikolaos & Che, Haochi [Show all 8 contributors for this article] (2026). Evolving Anthropogenic and Natural Aerosol Sources in the High Arctic. Full text in Research Archive
• Vartun, Marika & Heie, Magnus (2026). Slik kan skolen løfte elevene som starter med færrest muligheter. Forskning.no. ISSN 1891-635X. doi: https:/www.forskning.no/barn-og-ungdom-partner-skole-og-utdanning/slik-kan-skolen-lofte-elevene-som-starter-med-faerrest-muligheter/2633496. Full text in Research Archive Show summary

  Det handler om hvordan skolen bruker pengene.

• Vartun, Marika (2026). Nei, mannlige lærere er ikke bedre på digitale ferdigheter enn kvinnelige lærere. Forskning.no. ISSN 1891-635X. doi: https:/www.forskning.no/digitalisering-laerere-partner/nei-mannlige-laerere-er-ikke-bedre-pa-digitale-ferdigheter-enn-kvinnelige-laerere/2629097. Full text in Research Archive Show summary

  Forskere finner ingen forskjeller i faktisk kompetanse.

• Vartun, Marika (2026). Ungdom med alvorlige adferdsproblemer: Hva skjedde med behandlingstilbudet under pandemien? Forskning.no. ISSN 1891-635X. doi: https:/www.forskning.no/barn-og-ungdom-helsetjenester-pandemi/ungdom-med-alvorlige-adferdsproblemer-hva-skjedde-med-behandlingstilbudet-under-pandemien/2615645. Full text in Research Archive Show summary

  Forskere har sett på hva som skjedde da Norge stengte ned.

• Vartun, Marika (2026). Nå vet forskerne mer om hva som virker for barn med nedsatt hørsel. Forskning.no. ISSN 1891-635X. doi: https:/www.forskning.no/barn-og-ungdom-partner-skole-og-utdanning/na-vet-forskerne-mer-om-hva-som-virker-for-barn-med-nedsatt-horsel/2606803. Full text in Research Archive Show summary

  Å lese høyt sammen med barna har store effekter.

• Mangset, Marte; Staven, Helle Dyrendahl & Olsen, Oskar Grannæs (2026). Symbolic victory, material constraint: framing, power, and taxation of fish farming wealth. Full text in Research Archive
• Ystrom, Eivind (2025). Forsker | Utdanning.no. [Internet]. utdanning.no. Full text in Research Archive Show summary

  – Du må stå opp hver dag og faktisk ha lyst til å drive med forskning, forteller Eivind.

• Chen, Jianan; Brinchmann, Ellen Irén & Braeken, Johan (2025). Setting Stopping Rules for Progressive Tests: A Practical and Transparent Toolkit. Full text in Research Archive
• Ystrom, Eivind (2025). Paracetamol under graviditet forårsaker ikke autisme eller ADHD. [Journal]. VG. Full text in Research Archive Show summary

  Norsk studie av 100 000 barn viser ingen årsakssammenheng.

• Ystrom, Eivind (2025). FHI beroliger: Ingen påvist sammenheng mellom paracetamol hos gravide og autisme hos barn. [Journal]. Sykepleien. doi: https:/sykepleien.no/2025/11/fhi-beroliger-ingen-pavist-sammenheng-mellom-paracetamol-hos-gravide-og-autisme-hos-barn. Full text in Research Archive
• Knoph, Rebecca; Lawrence, Joshua; Kulesz, Paulina & Francis, David (2025). Diverging Effects of Lexical Dimensions in Speed and Accuracy. Full text in Research Archive Show summary

  Lexical decision tasks often prioritize reaction time as the main performance metric, discarding accuracy information beyond omitting incorrect trials. While established relationships exist between lexical dimensions, such as word length and frequency, and reaction time, the link to accuracy remains underexplored. This study analyzes word-level data from the English Lexicon Project (40,481 words; Balota et al., 2007) and the British Lexicon Project (28,730 words; Keuleers et al., 2012) to examine how lexical dimensions relate to mean reaction time and word-level accuracy. Multigroup SEM results indicate that certain latent lexical dimensions (Knoph et al., 2023) facilitate quick responses but may hinder accuracy, and conversely, may prompt participants to slow down and increase correct responses. Our findings suggest that speed in lexical decision tasks is not necessarily advantageous—while quick responses can correlate with accuracy, they are not synonymous. This work highlights the importance of further research on the distinction between reaction time and accuracy as separate constructs in understanding cognitive processes in reading.

• Kartushina, Natalia; Mayor, Julien; White, Michelle Jennifer; Gundersen, Anni Sofie Myrtveit; Onnis, Luca & Hagelund, Silje [Show all 9 contributors for this article] (2025). Reliability of acoustic measures of infant-directed speech between lab and home environments and play and reading contexts. Full text in Research Archive
• Ofstad, Sverre Berg & Andersson, Björn (2026). Karakterulempen ved å velge realfag: I hvilken grad veier realfagspoengene opp for den? Universitetet i Oslo. doi: https:/www.uv.uio.no/cemo/english/about/news-events-and-publications/news/2026/bonus-points-natural-science.html. Full text in Research Archive

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