Biostatistics & Study Design USMLE Step 1 Practice Question
A 58-year-old man with no prior colorectal cancer screening presents for evaluation. A new blood test measuring carcinoembryonic antigen (CEA) currently uses a threshold of 10 units/mL to define positive results. His CEA is 7 units/mL, and colonoscopy is normal. Investigators lower the diagnostic threshold to 6 units/mL to identify more early cancers. Which of the following best describes the most likely effect of lowering this cutoff value?
Answer choices
- AIncreased sensitivity and increased specificity
- BDecreased sensitivity and decreased specificity
- CDecreased sensitivity and increased specificity
- DNo change in sensitivity or specificity
- EIncreased sensitivity and decreased specificityCorrect answer
- FIncreased negative predictive value and decreased positive predictive value
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