Table 2.

Univariate analysis and multivariate analysis of RCEMS migration

Variable	Univariate analysis			Multivariate analysis
	OR	95% CI	P	OR	95% CI	P
Age	0.983	0.953–1.014	0.289
Gender	1.405	0.569–3.472	0.461
Location			0.367			0.071
Proximal	1			1
Middle	0.933	0.256–3.399	0.917	0.746	0.141–3.934	0.729
Distal	1.901	0.696–5.193	0.210	4.761	1.046–21.678	0.044
Grade of stricture length			0.023			0.006
≦10 mm	1		0.028	1
> 10 and < 20 mm	0.336	0.113–0.999	0.05	0.128	0.026–0.623	0.011
≧20 mm	0.214	0.066–0.697	0.01	0.085	0.017–0.426	0.003
Hydronephrosis–cortex ratio			0.377			0.059
≦5	1			1
> 5 and < 10	1.173	0.225–6.105	0.850	1.083	0.135–8.691	0.940
≧10	3.079	0.635–14.929	0.163	13.396	1.584–113.275	0.017
Balloon dilation	3.025	1.198–7.641	0.019	7.879	1.995–31.111	0.003
Diameter of wasting of RCEMS one day after surgery (mm)	8.726	2.952–25.794	< 0.001	2.417	1.554–3.760	< 0.001