Epidemiology & Screening · NEET PG Preparation Community Medicine (PSM)
A new diagnostic test for typhoid fever is evaluated against blood culture (gold standard). Out of 200 confirmed typhoid patients, 160 test positive.…
Practice question from Epidemiology & Screening (NEET PG Preparation Community Medicine (PSM)), with the correct answer and a step-by-step solution.
medium · MCQ · Q-796B60
A new diagnostic test for typhoid fever is evaluated against blood culture (gold standard). Out of 200 confirmed typhoid patients, 160 test positive. Out of 300 non-typhoid patients, 60 test positive. What is the sensitivity and specificity of the test, respectively?
- A.80% and 80%Correct answer
- B.80% and 60%
- C.60% and 80%
- D.90% and 70%
Solution
Sensitivity is the ability of a test to correctly identify those with the disease (True Positives / All Diseased) = . Specificity is the ability to correctly identify those without the disease (True Negatives / All Non-Diseased). Total non-diseased = 300, False positives = 60, so True Negatives = . Specificity = .
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