Table 3:

Contingency 2 × 2 matrix of patient subgroup counts based on the occurrence of an item A or item B, from which association metrics like prevalence, positive predictive value (PPV), and relative risk (RR) can be estimated.

Subgroup	B	!B	Total
A	N ABt	N A −N ABt	N A
!A	N B −N ABt	N−N A −N B +N ABt	N−N A
Total	N B	N−N B	N