Biostatistics & Study Design USMLE Step 1 Practice Question
A team develops a questionnaire to measure asthma control in adolescents. Pediatric pulmonologists review the draft noting it includes wheeze frequency and rescue inhaler use but omits nighttime awakenings and exercise limitationâkey domains of asthma control. A pilot study of 120 patients shows the current instrument correlates poorly (r=0.42) with FEV1 decline. Experts note medication adherence documentation is adequate. Which aspect of instrument quality are the reviewers primarily attempting to improve?
Answer choices
- AContent validityCorrect answer
- BSelection bias
- CTest retest reliability
- DPositive predictive value
- EPrecision
- FCriterion validity
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