Sample Description
The British Household Panel Survey (BHPS) began in 1991, and in 2010 it was incorporated into the larger UKHLS29 (also known as Understanding Society), which is a longitudinal panel survey of 40,000 UK households from England, Scotland, Wales, and Northern Ireland. Since 1991, annual interviews have collected sociodemographic information, and in 2011–2012, biomedical measures and blood samples for BHPS participants were collected during a nurse visit in the participant’s home. Respondents were eligible to give a blood sample if they had taken part in the previous main interview in English; were 16 or older; lived in England, Wales, or Scotland; were not pregnant; and met other conditions detailed in the user guide.30 For each participant, non-fasting blood samples were collected through venipuncture; these were subsequently centrifuged so that plasma and serum were separated, and samples were aliquoted and frozen at −80°C. DNA has been extracted and stored for genetic and epigenetic analyses.