Chapter 126 Screening for Disease Q&A (1 of 3) Sample Questions

1. A disease screening test true positive cases were 140 and non-cases were 1000. What is the positive predictive value (PPV)?
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  1. A. 99%
  2. B. 14%
  3. C. 12.3%
  4. D. 84%
Answer
Ans: C
Tips:
True positive 1000
False positive 1140

False negative 19000
True negative 19060
Positive predictive value = true positive/all positive
(140/1140)x 100 = 12.3%