Biostatistics & Study Design USMLE Step 1 Practice Question
A psychiatry research group develops a novel 12-item anhedonia scale in 200 patients with major depressive disorder (mean age 42, BP 128/82, HR 88) and 100 healthy controls (BP 120/76, HR 72). The scale correlates strongly with Hamilton Depression Rating Scale scores (r=0.87), weakly with serum sodium (r=0.12), and significantly distinguishes MDD patients from controls (p<0.001). Notably, anhedonia scores show no correlation with concurrent anxiety severity. These findings most strongly support which psychometric property of the scale?
Answer choices
- AConstruct validityCorrect answer
- BSpectrum bias
- CInterrater reliability
- DCriterion validity only
- ECase fatality
- FTest-retest reliability
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