A 62-year-old man presents with a 3-month history of intermittent hematochezia. Vital signs: BP 128/82, HR 92, RR 16, Temp 37.2°C, SpO2 98% on room air. A screening blood test for a colon cancer biomarker currently uses a threshold of 10 units/mL; his level is 8 units/mL. Investigators lower the threshold to 6 units/mL. Hemoglobin is 11.2 g/dL. Recent colonoscopy shows no polyps. Which effect is most likely?
- A)No change in sensitivity or specificity
- B)Increased sensitivity and decreased specificityGABARITO
- C)Decreased sensitivity and decreased specificity
- D)Decreased sensitivity and increased specificity
- E)Increased sensitivity and increased specificity
Explicação
Lowering the cutoff value makes it easier for the test to become positive, so more true positives are captured and sensitivity increases. At the same time, more false positives occur, which lowers specificity. This is the standard tradeoff for screening thresh... Ver explicação completa e trilha adaptativa →