Table VIII.

Multivariate analysis of the association between pelvic anatomical parameters and intraoperative blood loss in the abdominoperineal resection group.

	Unstandardized coefficient		Standardized coefficient
Model	B	SE	β	t	P-value
(Constant)	229.465	214.829		1.068	0.304
Anteroposterior diameter of the mid-pelvis	22.429	4.322	2.498	5.189	<0.001
Anteroposterior diameter of the pelvic outlet	−14.673	2.908	−1.239	−5.045	<0.001
Interspinous diameter	−5.594	1.600	−0.619	−3.495	0.004
Depth of the sacrococcygeal curvature	13.276	4.510	0.747	2.944	0.011
Sacropubic distance	−8.840	2.767	−1.004	−3.195	0.006

R=0.843, R²=0.711, R_C²=0.608, F=6.904, Model utility test: P=0.002. SE, standard error.