Table 3.

Comparison of Anorectal Manometry Findings and BET with Rectal Evacuation on Defecography in Constipated Patients (n=158)

HR-ARM parameter abnormality	Evacuation, No.		P value	Evacuation, median, %	Sensitivity, %	Specificity, %	Positive predictive value, %	Negative predictive value, %
	Normal	Reduced
Prolonged BET			<.001
Normal	88	20		78	N/A	N/A	N/A	N/A
Abnormal	21	29		18	59	81	58	81
Gradient			<.001
Normal	94	27		74	N/A	N/A	N/A	N/A
Abnormal	15	22		16	45	86	59	78
Gradient and BET			<.001
Both normal	78	13		79	N/A	N/A	N/A	N/A
Either abnormal	26	21		35	73	72	54	86
Both abnormal	5	15		3	31	95	75	75
Resting anal pressure			.25
Normal	100	42		70	N/A	N/A	N/A	N/A
Abnormal	9	7		33	14	92	44	70
Anal squeeze increment			.73
Normal	85	37		70	N/A	N/A	N/A	N/A
Abnormal	24	12		60	24	78	33	70
Residual anal pressure			<.001
Normal	100	34		73	N/A	N/A	N/A	N/A
Abnormal	9	15		12	31	92	63	75
Rectal pressure increase			.53
Normal	103	45		70	N/A	N/A	N/A	N/A
Abnormal	6	4		37	8	94	40	70
Anal relaxation			.95
Normal	93	42		66	N/A	N/A	N/A	N/A
Abnormal	16	7		70	14	85	30	69
Urge sensation			.013
Normal	101	40		70	N/A	N/A	N/A	N/A
Abnormal	5	8		3	17	95	62	72

Abbreviations: BE, balloon expulsion time; HR-ARM, high-resolution anorectal manometry; N/A, not applicable.

^aIncomplete rectal evacuation was defined as <25%. Prolonged BET was defined as >60 seconds.