PPV function

calculates the positive predictive value (PPV) of a diagnostic test.

The positive predictive value (PPV) of a dianostic test is the probability that someone with a positive diagnostic test for a condition does have the condition. The PPV can easily be calculated from the prevalence, the sensitivity, and the specificity, but this function automates the procedure.

PPV(sens, spec, prev)

Arguments

• sens: the sensitivity of the test
• spec: the specificity of the test
• prev: the prevalence of the disease

Returns

the positive predictive value of the test

References

van Hulst, R. 2018. Evaluating Scientific Evidence. ms.

Author(s)

Robert van Hulst

See Also

NPV

Examples

PPV(0.9, 0.8, 0.003)