Biostatistics & Study Design USMLE Step 1 Practice Question
A 38-year-old woman with systemic lupus erythematosus (ANA positive, complement levels low) presenting with fatigue and arthralgia enrolls in a treatment trial. Vital signs: BP 128/82, HR 92, RR 16, Temp 37.2°C, SpO2 98% on room air. She denies fever or dyspnea. The protocol specifies that a 4-point decrease on the 0-100 fatigue severity scale represents the smallest change patients perceive as clinically meaningful. Which term best describes this threshold?
Answer choices
- AType I error
- BLikelihood ratio
- CStandard error of the mean
- DMinimal clinically important differenceCorrect answer
- ERegression coefficient
- FNumber needed to treat
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