Linking the Twins Early Development Study (TEDS) with NHS electronic health records

The Twins Early Development Study (TEDS) is a longitudinal population study of over 10,000 twin pairs born in England and Wales between 1994 and 1996. As the twins enter their thirties, a primary focus of TEDS is to better understand the development of common physical and mental health problems and the relationship with the different social milestones of adulthood (e.g. employment, partnerships, and/or parenthood). With over 30 years of prospectively collected questionnaire and genetic data, the study is uniquely placed to answer questions about the health challenges facing young adults today. Incorporating linked medical records with the existing research data will provide a different data perspective on our twin’s health status and outcomes and to support more equitable research by helping to address both response and attrition bias. This paper provides an overview of the protocol to link TEDS participants to electronic health records collected by the UK National Health Service (NHS). It will outline the linkage process, characterise the available linked study sample and NHS datasets, and describe the legal basis for this work.