Table 4.

Multivariate analysis (logistic regression) for variables predicting ESWL failure for DUC.

Variable	B	SE	Exp(B)	95% CI for Exp(B)	P
BMI (kg/m2)
<25 (reference)	0		1
25–29	−0.019	0.759	0.981	0.222–4.342	0.980
⩾30	2.480	0.875	11.95	2.15–66.32	0.005
Stone
Length (mm)	0.303	0.136	1.354	1.038–1.766	0.025
Width (mm)	0.282	0.170	1.326	0.950–1.851	0.010

Exp(B) is the odds ratio, i.e. the ratio between the probabilities of failure due to the increase in the predictor value by one to its original probability. B, regression coefficient.