A study investigated the effect of a statin on people with high blood cholesterol. Over 5 years, 4000 people were given the statin and 4000 people were given a placebo.
The Table shows the results.
Table
| Group | Mean decrease in blood cholesterol in mmol/dm3\text{mmol/dm}^3mmol/dm3 | Number of people who had a heart attack | Number of people who stopped taking the tablets because of side effects |
|---|---|---|---|
| statin | 1.2 | 96 | 180 |
| placebo | 0.1 | 160 | 120 |
Calculate the percentage of people in each group who had a heart attack.
Calculate the percentage reduction in the number of heart attacks in the statin group compared with the placebo group.
Explain why fewer people in the statin group had a heart attack.
Suggest why some people in the placebo group stopped taking the tablets because of side effects.
Use the data to evaluate whether all people with high blood cholesterol should take statins for life.
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.