Comprehensive Analysis of Lifestyle Factors

Covariates were selected based on a pre-defined directed acyclic graph (online Supplemental Figure S1). Age was determined from birthdate (acquired from central registry, updated by participant) and the date when the accelerometry started (derived from the accelerometers). Information on the other covariates were obtained from the anthropometric measurements conducted by the trained nurses and the self-report questionnaire completed during the recruitment, including body mass index (BMI), body fat percentage, ethnicity, Townsend deprivation index (TDI), smoking status, menopause status, history of hysterectomy, and number of children. BMI was constructed as weight in kilograms divided by height in meters squared. The height was measured using the Seca 240 measuring rod, while the weight and the body fat percentage were assessed using the Tanita BC418MA body composition analyzer. TDI is a composite metric of material deprivation that incorporates unemployment, non-car ownership, non-home ownership, and household overcrowding, with higher values indicating lower socio-economic status [13 (link)]. TDI was assigned to each participant according to their postcode and the result of preceding national census. Details of these covariates can be found on the website of the UK Biobank.