At each visit, participants were sent a detailed questionnaire to complete at home; questionnaires were reviewed for completeness during the clinic visit. The questionnaires asked about a variety of health conditions.
In most visits, participants were asked to:
- rate their general health (personally and as compared to others the same age), and their physical and emotional functioning using questions similar to those on the RAND 36-Item Short Form Health Survey (SF-36) developed as part of the Medical Outcomes Study;
- indicate the number of doctor and hospital visits in past year, and reasons for hospital visits;
- indicate whether they had ever been told by a doctor that they had any of an extensive list of chronic diseases, including different types of cardiovascular disease, hypertension, pulmonary disease, kidney disease, liver disease, thyroid disease, osteoporosis and different types of cancer. Participants were also asked to indicate age at first diagnosis of each type of cancer.