Table 6. Multivariable analysis for overall survival.

Variable	Available cases	HR	95% CI	P
Age at start of dialysis	298	1.10	1.05 to 1.15	<0.001
Active smoking	298			0.008
yes versus no	48 vs. 250	3.72	1.50 to 9.23

Final multivariable model using a stepwise model building procedure. Estimated hazard ratio (HR) with 95% confidence interval (CI) and p-value of the likelihood ratio test. For pairwise comparisons, confidence intervals instead of p-values are given (p-value of Wald test ≤ 0.05 if and only if confidence interval does not contain 1)