Table 4.

Examining the effect of ureteral stone impaction on outcomes corrected for confounders using multivariate logistic regression

Outcomes	Odds ratio	95% confidence interval	p value
Model 1: Association of stone impaction and outcomes after ureteroscopy (univariate analysis)
Stone-free rate	0.53	0.46–0.62	<0.001
Intra-operative complications	2.77	2.26–3.40	<0.001
Post-operative complications	1.59	2.65–5.98	<0.001
Model 2: Association of impaction on outcomes after ureteroscopy corrected for baseline characteristics and stone characteristics found significant in the prediction model
Stone-free rate	0.57	0.48–0.67	<0.001
Intra-operative complications	2.71	2.17–3.38	<0.001
Post-operative complications	1.43	1.04–1.98	0.030
Model 3 Association of impaction on outcomes after ureteroscopy corrected for baseline characteristics and clinically possible confounders
Stone-free rate	0.57	0.48–0.68	<0.001
Intra-operative complications	3.23	2.54–4.11	<0.001
Post-operative complications	1.34	0.95–1.90	0.095