Scientists recorded alcohol consumption and new cases of liver disease in four groups of adults during one year. All the adults were followed for the same length of time.
| Alcohol consumed / g per day | Number of adults | New cases of liver disease |
|---|---|---|
| 0 to 5 | 20 000 | 12 |
| 6 to 20 | 30 000 | 45 |
| 21 to 40 | 16 000 | 48 |
| More than 40 | 7 000 | 35 |
Two interpretations of the results were suggested.
Interpretation 1: Adults consuming 21 to 40 g of alcohol per day had the greatest risk because this group had the most new cases.
Interpretation 2: Adults consuming more than 40 g of alcohol per day had the greatest risk, and risk increased with alcohol consumption.
Evaluate which interpretation is better supported by the study. Use calculations and your knowledge of biology in your answer.
304 exam-style questions on AQA GCSE Biology 2.2 Animal tissues, organs and organ systems, covering 2.2.1 The human digestive system, 2.2.2 The heart and blood vessels, 2.2.3 Blood, 2.2.4 Coronary heart disease: a non-communicable disease, 2.2.5 Health issues, 2.2.6 The effect of lifestyle on some non-communicable diseases, and 2.2.7 Cancer. Each one has a worked solution and a mark scheme showing where the marks go.