A town introduces exercise classes and a campaign to stop smoking in the same year. Cardiovascular disease rates fall over the next five years.
Which change to the study would best help identify the contribution of the exercise classes?
Compare attendees with non-attendees, without recording their changes in smoking behaviour.
Compare similar towns without either programme, before and after the five years.
Compare similar towns with the smoking campaign, with and without exercise classes.
Compare disease totals from different years, without recording changes in population size.
44 exam-style questions on Edexcel GCSE Biology 5.4 Non-communicable diseases, covering 5.4.1 Interaction of factors in non-communicable disease, 5.4.2 Lifestyle factors and non-communicable disease, and 5.4.3 Treatments for cardiovascular disease. Each one has a worked solution and a mark scheme showing where the marks go.