Table 2: Contingency table.
(a)

Cystography test no leakageCystography test leakageTotals

Methylene blue test no leakage 591271
Methylene blue test leakage122032

Totals7132

(b)

Cystography test no leakageCystography test leakage

Methylene blue test no leakage 83.1% true positive16.9% false positive
Methylene blue test leakage37.5% false negative62.5% true negative