The age 50 sweep comprised a 60 minute CAPI interview (which included a series of memory and concentration tasks and a 10 minute self-completion section), and a 16-page self-completion questionnaire which was mailed to all cohort members before their interview.
The main topics covered in the interview were: household composition, housing, relationships, pregnancies, children and wider family, employment and income, education and training, use of computers, physical and mental health, smoking and drinking, exercise, height and weight, social participation and voting. The interview also included four cognitive assessments measuring memory, verbal fluency and concentration.
The main topics covered in the paper self-completion questionnaire were: leisure activities, personality, sleep, values, attitudes and well-being. An open question at the end asked respondents to describe their imagined lives at 60.
Cohort members (and their partners) were also asked for permission to link their survey responses with health records held by the NHS and economic records held by the Department of Work and Pensions (DWP) and Her Majesty’s Revenue and Customs (HMRC).