February, 2003
© 2000, 2001, 2003 Scott S. Emerson, M.D., Ph.D.
Diagnostic Testing: 10
Role of Prevalence
Bottom line:
·
Predictive value of a diagnostic test depends heavily on the prevalence of the disease
More generally:
·When using Bayes rule, to calculate probabilities, the computed values are specific to the assumed “prior” information
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