• Exposure variables. The exposure variables are the presence of long-standing conditions. These are collected within the SYC as self-reported long-standing conditions. Twelve named conditions are recorded, along with an "other" condition, which includes free-text to allow the respondent to state the condition. These conditions (and their prevalence amongst a preliminary sample of people aged 60 to 74 in the SYC) are: Depression (8%), Anxiety (10%), Fatigue (19%), Pain (28%), Insomnia (8%), Diabetes (10%), Breathing problems (13%), High blood pressure (31%), Heart disease (10%), Osteoarthritis (16%), Stroke (3%), Cancer (5%) and Other (29%).