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Related Experiment Video

Updated: Jul 11, 2026

Use of a Video Scoring Anchor for Rapid Serial Assessment of Social Communication in Toddlers

Use of a Video Scoring Anchor for Rapid Serial Assessment of Social Communication in Toddlers

Published on: March 14, 2018

[School performance--no difference between twins and singletons--secondary publication].

Kaare Christensen¹, Inge Petersen, Axel Skytthe

¹Syddansk Universitet, Det Danske Tvillingregister, Epidemiologi, Institut for Sundhedstjenesteforskning, Odense Universitetshospital, Børneafdelingen. kchristensen@health.sdu.dk

Ugeskrift for Laeger

|October 5, 2007

Summary

Twins born recently show similar school performance to singletons, unlike older studies. Advances in healthcare and living conditions likely explain this improved outcome for twins.

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Using Cholesky Decomposition to Explore Individual Differences in Longitudinal Relations between Reading Skills

Using Cholesky Decomposition to Explore Individual Differences in Longitudinal Relations between Reading Skills

Published on: September 17, 2019

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Last Updated: Jul 11, 2026

Use of a Video Scoring Anchor for Rapid Serial Assessment of Social Communication in Toddlers

Use of a Video Scoring Anchor for Rapid Serial Assessment of Social Communication in Toddlers

Published on: March 14, 2018

Using Cholesky Decomposition to Explore Individual Differences in Longitudinal Relations between Reading Skills

Using Cholesky Decomposition to Explore Individual Differences in Longitudinal Relations between Reading Skills

Published on: September 17, 2019

Area of Science:

Pediatrics
Twin Studies
Educational Psychology

Context:

Older studies (50+ years ago) suggested lower IQ in twins compared to singletons.
Register-based study in Denmark (1986-1988) included 3411 twins and 7796 singletons.
Investigated adolescent school performance differences between twins and singletons.

Purpose:

To determine if the historical IQ gap between twins and singletons persists.
To assess adolescent school performance in a contemporary twin cohort.
To identify potential factors influencing twin school performance.

Summary:

No significant difference in adolescent school performance was found between twins and singletons.
This finding remained consistent even after controlling for birth weight, gestational age, parental age, and parental education.
The study suggests improvements in living conditions and medical care have positively impacted twin development.

Impact:

Challenges the long-held notion of cognitive disadvantages for twins.
Highlights the positive influence of advancements in obstetrics and pediatrics on twin outcomes.
Provides evidence for the equalizing effect of improved societal and medical factors on twin and singleton development.