In a genetically informed twin study, the effect of shared family environment was substantially reduced among twins whose tracking was delayed until a later age¶
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Evidence · 1 study · theoreticalr2·q2
Currency · newest study 2022 · not yet checked against its sources · not reviewed by a person
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q2 i? Using a twin design from the Netherlands, the effect of shared family environment was substantially reduced among twins whose tracking was delayed until a later age, consistent with delayed streaming improving equality of opportunity. → Peter M. Visscher 2022
Evidence¶
Peter M. Visscher 2022¶
Peter M. Visscher. (2022). Genetics of cognitive performance, education and learning: from research to policy? npj Science of Learning. https://doi.org/10.1038/s41539-022-00124-z
q2 · i? · theoretical · r2
The commentary reports Knigge and colleagues' genetically informed twin study using the Dutch age-12 national tracking exam on thousands of identical and non-identical twin pairs, some tracked at a later age. The main result was that the shared family environment effect was substantially reduced with delayed tracking. No effect size is printed.
"Their main result, using state-of-the-art statistical modelling, was that the effect of shared family environment was substantially reduced among twins whose tracking was delayed until a later age"
Discussion¶
Related Claims¶
- Genetic and environmental variance components of educational achievement decrease with increasing parental SES — related
- Average educational achievement at age 12 increases with parental SES in the Netherlands — related
- Dizygotic twin correlations for educational attainment are consistently higher than non-twin sibling correlations across countries, suggesting twin-specific shared environments are a general phenomenon — related
- Delaying tracking is associated with a larger genetic influence especially among low-performing students, supporting the compensation hypothesis (H2b) — related
- Delaying definite tracking is associated with a larger genetic influence and a lower shared-environmental influence on secondary educational attainment among Dutch twins — related
- The association between delayed tracking and larger genetic influence is driven mostly by reduced primary effects (influences common to performance and attainment), not secondary effects — related
- Parental education is not related to whether children are tracked immediately or delayed — related
Page metadata
| Field | Value |
|---|---|
type |
claim |
id |
delayed-tracking-reduced-family-environment-effect |
title |
In a genetically informed twin study, the effect of shared family environment was substantially reduced among twins whose tracking was delayed until a later age |
description |
In a genetically informed twin study, the effect of shared family environment was substantially reduced among twins whose tracking was delayed until a later age |
status |
review |
evidence_strength |
weak |
newest_evidence |
2022 |
generated |
by process:wiki-ingest on 2026-10-26 |
trust |
unverified — no one has confirmed this page's content |
sources |
1 — peter-m-visscher-2022 |
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