Epidemiology & Prevention USMLE Step 1 Practice Question
A researcher conducting a cross-sectional survey finds that patients with depression have higher rates of chronic pain compared to those without depression (OR = 3.2, 95% CI 2.1-4.8, p < 0.001). The researcher concludes that depression causes chronic pain. Which of the following represents the primary limitation of this interpretation?
Answer choices
- AOdds ratios cannot demonstrate causation
- BCross-sectional studies cannot establish temporal precedenceCorrect answer
- CSelection bias was not controlled
- DThe p-value indicates the result is unreliable
- EThe confidence interval is too narrow
- FReverse causality cannot be excluded in observational study designs
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