Biostatistics & Study Design USMLE Step 1 Practice Question
A data safety monitoring board reviews efficacy outcomes every 3 months during a large stroke prevention trial enrolling 2,400 patients. The biostatistician notes that repeated looks at accumulating dataâcurrently showing a trend toward reduced ischemic stroke incidence (p=0.08 at interim analysis)âincrease the chance of a false positive result unless the significance threshold is adjusted downward. No safety signals have emerged. Which statistical concept is being described?
Answer choices
- AAlpha spendingCorrect answer
- BRegression to the mean
- CEffect modification
- DVerification bias
- EAllocation concealment
- FBonferroni correction
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