From: Estimates of sensitivity and specificity can be biased when reporting the results of the second test in a screening trial conducted in series
Test 2
Observed Disease Status
Probability
+
p D [FN(1) - FN(1, 2)]/Q
-
(1 - p D )FP(2)/Q
p D p E FN(1,2)/Q
[(1 - p D )TN(2) + p D (1 - p E )FN(1, 2)/Q