Begging the question

Bus passes: do they make you fat? Actually, no, according to research from the Department of Primary Care and Public Health at Imperial College London. Using data from the English Longitudinal Study of Ageing, the team found (via the mysteries of logistic regression analysis) that the provision of bus passes to people aged 60 + has encouraged increased use of public transport and that this is associated with lower levels of obesity. Or, to put it more succinctly, bus passes "may have conferred a protective effect against obesity."