Redd and co-workers found the sensitivity of their rapid diagnostic test for group A streptococcal pharyngitis to be 62.8% and its specificity to be 96.9%. Furthermore, the positive predictive value of the test was determined to be 91.5%, sufficiently high to significantly influence the care provided to their patients.
We strongly disagree with the authors' conclusion that their findings can be extrapolated to the general pediatric setting. Bayes theorem clearly relates a test's positive predictive value to its sensitivity as well as to the prevalence of true disease in the population.
- Copyright © 1989 by the American Academy of Pediatrics