All eligible study members were contacted: 3,053 study members gave information

Data collection was carried out at home visits to cohort members by research nurses recruited and employed by the National Centre for Social Research. An electronic questionnaire was administered by nurses using laptop computers to ask about home and family circumstances, health, disability, employment, earnings, social participation, smoking and exercise habits, and experience of disturbing life events. Nurses administered tests of lower body strength and balance, and made body measurements, and measured blood pressure, respiratory function, and grip strength, and examined hands and knees for signs of osteoarthritis. They also took a blood sample and a cheek swab from which DNA was derived. Measures were also derived from the non-fasting blood sample of cardiovascular risk factors (cholesterol, HDL cholesterol, triglyceride, glycosolated haemoglobin) and nutritional markers (red cell folate, plasma folate, plasma B12, plasma ferritin). Nurses left a diet diary to be completed over the next 6 days and returned by post. During the course of the home visit the cohort member was asked to complete a short paper questionnaire that included questions about diet and alcohol consumption, hearing and vision, spare-time activities, relationships with others, the short (28 item) General Health Questionnaire including the psychosis screening questions, and questions bladder problems (men only), menopausal symptoms and the use of hormone replacement therapy (women only).  

In addition a pilot study took place in two locations in order to test cohort members’ response to invitation to a clinic for data collection. 

The study team and specialist colleagues trained the nurses over 3 consecutive days. The nurses’ instruction manual is available here

• Household and housing information
• Marital status (and information on spouse employment)
• Information on children and grandchildren
• Hospital admissions
• Parental information
• Rose Angina
• Intermittent claudication
• Heart trouble
• General health problems
• Cancer
• Chest and cough trouble (MRC questionnaire on respiratory symptoms)
• Smoking
• Breast screening and mammograms
• Actvities of daily living
• Physical capacity
• Life events
• Employment history and earnings
• Finance and financial hardship
• Physical examination
• Cognitive tests
• General Health Questionnaire (short form)
• Psychosis screening questions
• Bladder problems (men only) 
• Menopausal symptoms and the use of hormone replacement therapy (women only) 
• Diet diary

• Form A Main Capi questionnaire
• Form B  Self Completion
• Form C Diet Diary
• Women's Health in the Middle Years