An ecological study finds that countries with higher fat consumption have higher rates of breast cancer. The error in concluding that high fat intake in individuals causes breast cancer based on this finding is called:
- A Ecological fallacy ✓
- B Confounding
- C Effect modification
- D Information bias
Correct answer: A. Ecological fallacy
Explanation
The ecological fallacy (also called the aggregation bias) occurs when associations observed at the group (population) level are incorrectly attributed to individuals. In ecological studies, the unit of analysis is the group, not the individual, so it is invalid to infer individual-level risk from group-level correlations. Confounding is a mixing of effects from a third variable.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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