Table 3 Cox proportional survival model with Hazard Ratios (HR) adjusted for age, sex, year of surgery and nation as covariates with 95% CI (confidence interval) for all reasons for revision up to 10 years after primary surgery
Variables | No of procedures | HR(95%CI) | p-value |
|---|---|---|---|
Age group | |||
55-64 | 5469 | 1.0 (ref) | |
< 55 | 2424 | 1.3 (1.1-1.5) | <0.001 |
65-74 | 4606 | 0.8 (0.7-0.9) | <0.001 |
≥ 75 | 1997 | 0.7 (0.6-0.8) | <0.001 |
Sex | |||
Male | 6272 | 1.0 (ref) | |
Female | 8224 | 1.0 (0.9-1.1) | 0.6 |
Year of surgery | |||
2000-03 | 2662 | 1.0 (ref) | |
2004-06 | 3664 | 1.2 (1.0-1.3) | 0.04 |
2007-09 | 4392 | 1.2 (1.0-1.4) | 0.02 |
2010-12 | 3778 | 1.3 (1.1-1.6) | 0.004 |
Nation | |||
Sweden | 2218 | 1.0 (ref) | |
Denmark | 4211 | 1.4 (1.2-1.7) | <0.001 |
Norway | 4157 | 1.2 (1.0-1.5) | 0.01 |
Finland | 3910 | 1.2 (1.0-1.4) | 0.05 |