Table 2 Notations for prevalence, sensitivity, and specificity

Pr(D + ; S)

Probability of true disease (D+) in population S [prevalence]

Pr(O +|D + ; S)

Probability of “positive” outcome based on the algorithm (O+) in a subset of S with true disease (D+) [sensitivity]

Pr(O −|D − ; S)

Probability of “negative” outcome based on the algorithm (O−) in a subset of S without true disease (D−) [specificity]