A new diagnostic test for diabetes is evaluated in 1000 individuals: 80 true positives, 20 false negatives, 40 false positives, and 860 true negatives. The specificity of the test is:
- A 80%
- B 90%
- C 95.6% ✓
- D 66.7%
Correct answer: C. 95.6%
Explanation
Specificity = TN/(TN+FP) = 860/(860+40) = 860/900 = 95.6%. Sensitivity = TP/(TP+FN) = 80/100 = 80%. Specificity measures the test's ability to correctly identify those without disease. Option A (80%) is the sensitivity, not specificity.
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.