Biostatistics & Study Design USMLE Step 1 Practice Question
A 48 year old man with alcohol use disorder is admitted for pancreatitis. Researchers study only hospitalized patients and find that among admitted patients, obesity appears negatively associated with alcohol use disorder. In the source population, however, both obesity and alcohol use independently increase hospitalization risk. Which of the following best explains the spurious inverse association seen in the hospitalized sample?
Answer choices
- ALead time bias
- BConfounding
- CCollider biasCorrect answer
- DObserver expectancy bias
- ERandom error
- FSelection bias due to differential recall of dietary habits
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