Medical Diagnostic Tests: A Review of Test Anatomy, Phases, and Statistical Treatment of Data

Table 7

2 × 2 contingency generic table.

Diagnostic test result	Disease present	Disease absent	Total
Positive	TP (true positive)	FP (false positive)	TP + FP
Negative	FN (false negative)	TN (true negative)	FN + TN
Total	TP + FN	FP + TN	n = TP + FP + FN + TN

Total on the rows represents the number of subjects with positive and respectively negative test results; total on the columns represents the number of subjects with (disease present) and respectively without (disease absent) the disease of interest; and the classification as test positive/test negative is done using the cutoff value for ordinal and continuous data.