. 2011 Feb;84(998):136–144. doi: 10.1259/bjr/28989463

Table 3. Diagnostic performance of MR defecography findings in the diagnosis of dyssynergic defecation.

Measurements	TPR^a	TNR^a	FPR^a	FNR^a	Sensitivity^b	Specificity^b	PPV^b	NPV^b	Accuracy^b
Impaired evacuation	18	7	23	0	100 (97–100)	23 (7–40)	44 (27–60)	100 (93–100)	52 (37–67)
Abnormal ARA-change	9	29	1	9	50 (24–76)	97 (89–100)	90 (66–100)	76 (61–91)	79 (67–92)
Paradoxical sphincter contraction	15	26	4	3	83 (63–100)	87 (73–100)	79 (58–100)	90 (77–100)	85 (74–96)
ARA+paradoxical sphincter contraction	17	26	4	1	94 (81–100)	87 (73–100)	81 (62–100)	96 (87–100)	90 (80–99)

Data are results from the consensus reading. Numbers in parentheses are 95% confidence intervals.

ARA, anorectal angle; ARA-change, calculated as [(ARA at straining)–(ARA at rest)]; FNR, false-negative results; FPR, false-positive results; NPV, negative predictive value; PPV, positive predictive value; TNR, true-negative results; TPR, true-positive results.

^aNumbers are absolute numbers of patients.

^bNumbers are percentages.