TABLE II.
| Hazard Ratio‡ | P Value§ | |
| Time | ||
| Zero to one year | Reference | — |
| More than one year to two years | 4.284 (3.818 to 4.807) | <0.001 |
| More than two years to three years | 5.524 (4.919 to 6.202) | <0.001 |
| More than three years to four years | 6.555 (5.835 to 7.365) | <0.001 |
| More than four years to five years | 7.438 (6.616 to 8.362) | <0.001 |
| More than five years to six years | 8.335 (7.408 to 9.379) | <0.001 |
| More than six years to seven years | 9.478 (8.413 to 10.679) | <0.001 |
| More than seven years to eight years | 10.584 (9.378 to 11.945) | <0.001 |
| More than eight years to nine years | 12.138 (10.710 to 13.757) | <0.001 |
| More than nine years to ten years | 15.189 (13.073 to 17.647) | <0.001 |
| Sex | ||
| Male | Reference | — |
| Female | 0.804 (0.758 to 0.852) | <0.001 |
| Head size | ||
| <32 mm | Reference | — |
| ≥32 mm | 0.832 (0.768 to 0.903) | <0.001 |
| Bearing type | ||
| Ceramic on ceramic | Reference | — |
| Ceramic on conventional polyethylene | 0.974 (0.843 to 1.127) | 0.725 |
| Ceramic on highly cross-linked polyethylene | 1.078 (0.938 to 1.240) | 0.292 |
| Metal on conventional polyethylene | 1.047 (0.929 to 1.179) | 0.452 |
| Metal on highly cross-linked polyethylene | 0.820 (0.747 to 0.901) | <0.001 |
| Fixation effects by age | ||
| Hybrid, forty-five to more than seventy-five years | Reference | — |
| Uncemented, forty-five to sixty-four years | 1.205 (1.008 to 1.442) | 0.041 |
| Cemented, forty-five to sixty-four years | 1.093 (0.869 to 1.374) | 0.448 |
| Uncemented, sixty-five to seventy-four years | 1.160 (1.023 to 1.315) | 0.021 |
| Cemented, sixty-five to seventy-four years | 1.048 (0.898 to 1.223) | 0.552 |
| Uncemented, seventy-five years and more | 1.575 (1.389 to 1.786) | <0.001 |
| Cemented, seventy-five years and more | 0.919 (0.789 to 1.070) | 0.275 |
*
The estimate (and standard error) for the intercept was −5.232 ± 0.088.
†
Fixed registry effects were included in this model (five coefficients), but the results are omitted from this table because a precondition of data sharing was no reporting of between-registry comparisons.
‡
The values are given as the hazard ratio, with the 95% CI, based on a normal distribution, in parentheses.
§
The p values are based on a normal distribution.