ArticleHormones and behavior2015
Academic performance of opposite-sex and same-sex twins in adolescence: A Danish national cohort study.
Article in Hormones and behavior, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
14 citing papers in PubMed, 27 citations in OpenAlex.
- Twin testosterone transfer hypothesis and the second-to-fourth digit ratio in females of same-sex and opposite-sex twin pairs: An exploratory study.Physiological reports · 2025Article
- Variability Matters.International journal of environmental research and public health · 2020Article
- Dementia risk in women higher in same-sex than opposite-sex twins.Alzheimer's & dementia (Amsterdam, Netherlands) · 2020Article
- Opposite-sex and same-sex twin studies of physiological, cognitive and behavioral traits.Neuroscience and biobehavioral reviews · 2020Review
- The Danish Twin Registry: An Updated Overview.Twin research and human genetics : the official journal of the International Society for Twin Studies · 2019Article
- Gender differences in cognitive function and grip strength: a cross-national comparison of four European regions.European journal of public health · 2019Article
- Evidence that prenatal testosterone transfer from male twins reduces the fertility and socioeconomic success of their female co-twins.Proceedings of the National Academy of Sciences of the United States of America · 2019Article
- Prenatal testosterone does not explain sex differences in spatial ability.Scientific reports · 2018Article
- Risk of epilepsy in opposite-sex and same-sex twins: a twin cohort study.Biology of sex differences · 2018Article
- Early-life mortality risks in opposite-sex and same-sex twins: a Danish cohort study of the twin testosterone transfer hypothesis.Annals of epidemiology · 2017Article
- Sex Differences in Human and Animal Toxicology.Toxicologic pathology · 2017Review
- Effect of maternal PCOS and PCOS-like phenotype on the offspring's health.Molecular and cellular endocrinology · 2016Review
- Differences in Religiousness in Opposite-Sex and Same-Sex Twins in a Secular Society.Twin research and human genetics : the official journal of the International Society for Twin Studies · 2016Article
- Effect of co-twin gender on neurodevelopmental symptoms: a twin register study.Molecular autism · 2016Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors at 3 institutions in 2 countries.
Funding
Abstract
Testosterone is an important hormone in the sexual differentiation of the brain, contributing to differences in cognitive abilities between males and females. For instance, studies in clinical populations such as females with congenital adrenal hyperplasia (CAH) who are exposed to high levels of androgens in utero support arguments for prenatal testosterone effects on characteristics such as visuospatial cognition and behaviour. The comparison of opposite-sex (OS) and same-sex (SS) twin pairs can be used to help establish the role of prenatal testosterone. However, although some twin studies confirm a masculinizing effect of a male co-twin regarding for instance perception and cognition it remains unclear whether intra-uterine hormone transfer exists in humans. Our aim was to test the potential influences of testosterone on academic performance in OS twins. We compared ninth-grade test scores and teacher ratings of OS (n=1812) and SS (n=4054) twins as well as of twins and singletons (n=13,900) in mathematics, physics/chemistry, Danish, and English. We found that males had significantly higher test scores in mathematics than females (.06-.15 SD), whereas females performed better in Danish (.33-.49 SD), English (.20 SD), and neatness (.45-.64 SD). However, we did not find that OS females performed better in mathematics than SS and singleton females, nor did they perform worse either in Danish or English. Scores for OS and SS males were similar in all topics. In conclusion, this study did not provide evidence for a masculinization of female twins with male co-twins with regard to academic performance in adolescence.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.