Epidemiology & Prevention USMLE Step 1 Practice Question
A 7 year old boy is diagnosed with acute lymphoblastic leukemia, and investigators design a case control study to evaluate household benzene exposure. They match each case to controls from the same home address and same school classroom. The final study finds no association. Which design problem most likely reduced the ability to detect a true exposure effect?
Answer choices
- ABerkson bias
- BOvermatchingCorrect answer
- CImmortal time bias
- DPublication bias
- ELead time bias
- FConfounding by socioeconomic status
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