In a mass cervical cancer screening programme using VIA (Visual Inspection with Acetic acid), the test's sensitivity for CIN 2+ is 70% and specificity is 79%. Shifting the cut-off to detect more cases (increasing sensitivity to 85%) would MOST likely result in:

• A Increased specificity and decreased false positive rate
• B Decreased specificity and increased false positive rate ✓
• C Unchanged specificity because sensitivity and specificity are independent
• D Increased PPV because more true cases are detected

Explanation

Sensitivity and specificity have an inverse relationship: increasing sensitivity (by lowering the positivity threshold to capture more true cases) inevitably decreases specificity and increases the false positive rate. The ROC curve illustrates this trade-off. In population-level screening like VIA, lowering the threshold means more women with normal cervices are called positive, leading to increased unnecessary colposcopy referrals. PPV would decrease (not increase) because more false positives are generated relative to true positives.

Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.