Scientists investigated the relationship between weekly exercise and new diagnoses of cardiovascular disease in adults.
The scientists selected adults so that each exercise group had a similar age distribution.
The table shows the results.
| Exercise per week (minutes) | New diagnoses of cardiovascular disease per 10 000 adults per year |
|---|---|
| 0 to 29 | 180 |
| 30 to 59 | 140 |
| 60 to 89 | 100 |
| 90 or more | 80 |
Adults in the highest exercise category had fewer new diagnoses than adults in the lowest exercise category.
Calculate the difference in diagnosis rate between these two categories.
Compare the diagnosis rates for adults exercising for 30 to 59 minutes and 60 to 89 minutes each week.
Explain why it was important for the exercise groups to have similar age distributions.
The adults in the 0 to 29 minute exercise group also ate more foods high in saturated fat.
Explain how this dietary difference could help account for the diagnosis rate in this group.
102 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.