Biostatistics & Study Design USMLE Step 1 Practice Question
A 50-year-old man with heart failure (ejection fraction 35% on echocardiography) on metoprolol and lisinopril completes a new 12-item questionnaire designed to measure medication adherence. He denies chest pain and maintains blood pressure of 128/82 mmHg with heart rate 68/min. Investigators want to assess whether the questionnaire items are internally consistent and measure the same underlying construct of adherence. Which statistical measure is most appropriate for evaluating this psychometric property?
Answer choices
- AKappa statistic
- BStandardized mortality ratio
- CCronbach alphaCorrect answer
- DPearson correlation coefficient
- EHazard ratio
- FIntraclass correlation coefficient
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