The TEDS Sample
Participants were identified from birth records of all twins born in England and Wales between 1994 and 1996. When the twins were around 12 months old, a parent or guardian of the twins was asked to complete a first contact booklet, which listed a comprehensive range of background variables (e.g. information about ethnic origin, job status and educational qualifications). This background information has been updated through the course of the study and has enabled comparisons of the TEDS sample against UK population data and against participants lost to attrition. These comparisons have led to the conclusion that, despite attrition, TEDS continues to be representative of the UK population, e.g. in terms of ethnicity, maternal education, and parental employment status. Zygosity of twins was determined either using parental questionnaires or, in instances where questionnaire results were unclear, by DNA typing. Data has been collected longitudinally at ages 2, 3, 4, 7, 8, 9, 10, 12, 14 and 16
Read more about this topic: Twins Early Development Study
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