A researcher studying the association between dietary fat intake and coronary artery disease finds that physically active individuals tend to both eat less fat and have lower CAD rates. Physical activity is acting as a:
- A Confounder ✓
- B Effect modifier
- C Mediator
- D Precision variable
Correct answer: A. Confounder
Explanation
A confounder is a variable that is associated with both the exposure and the outcome, is not on the causal pathway, and can distort the true association. Physical activity fulfils all three criteria: it is associated with dietary fat intake (exposure) and independently with CAD risk (outcome) and is not on the causal pathway between diet and CAD. An effect modifier changes the magnitude of association at different levels; a mediator lies on the causal pathway.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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