The positive likelihood ratio (y-axis) increases with the PPV (x-axis) for a given value of the base rate (see color code). However, for a given value of the PPV, the positive likelihood ratio decreases as the base rate increases. The vertical dashed lines represent the two estimates of the PPV (16% and 47%) we derived for the RPCB. Typically, a positive likelihood ratio between 1 and 2 is considered weak evidence, while ratios between 2 and 10 constitute moderate evidence, and ratios higher than 10 constitute strong evidence. A ratio of less than one indicates that a test is actively uninformative.