Table 1 Description of the datasets
Variable | Statistics | Control | DePuy | Biomet | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Â | Â | Males | Females | All | Males | Females | All | Males | Females | All |
Sample size | Number | 44,468 | 69,304 | 113,772 | 1093 | 641 | 1734 | 315 | 449 | 764 |
| Â | % by sex | 39.1 | 60.9 | Â | 63.0 | 37.0 | Â | 41.2 | 58.8 | Â |
Revisions | Number | 596 | 740 | 1336 | 132 | 169 | 301 | 15 | 36 | 51 |
| Â | % by sex | 44.6 | 55.4 | Â | 43.9 | 56.1 | Â | 29.4 | 70.6 | Â |
Deaths | Number | 4074 | 5512 | 9586 | 56 | 31 | 87 | 40 | 37 | 77 |
| Â | % by sex | 42.5 | 57.5 | Â | 64.4 | 35.6 | Â | 51.9 | 48.1 | Â |
Censored | Number | 39,798 | 63,052 | 102,850 | 905 | 441 | 1346 | 260 | 376 | 636 |
| Â | % by sex | 38.7 | 61.3 | Â | 67.2 | 32.8 | Â | 40.9 | 59.1 | Â |
Age | Mean | 69.4 | 71.5 | 70.7 | 59.9 | 61.5 | 60.5 | 67.8 | 67.8 | 67.8 |
| Â | StDev | 9.1 | 9.3 | 9.2 | 6.9 | 8.5 | 7.6 | 7.3 | 7.6 | 7.5 |
IMD | Mean | 19 | 19 | 19 | 18.6 | 17.3 | 18.1 | 11.6 | 12.3 | 12 |
| Â | StDev | 9.2 | 9.2 | 9.2 | 10.8 | 10.4 | 10.7 | 5 | 5.2 | 5.2 |
HeadSize | Mean | 32.6 | 30.2 | 31.2 | 49.4 | 45.1 | 47.8 | 38 | 38 | 38 |
| Â | StDev | 6.5 | 3.8 | 5.2 | 3 | 2.6 | 3.5 | 0 | 0 | 0 |
Fixation | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
Cemented | Number | 18,787 | 36,150 | 54,937 | 71 | 35 | 106 | 8 | 7 | 15 |
| Â | % | 42.2 | 52.2 | 48.3 | 6.5 | 5.5 | 6.1 | 2.5 | 1.6 | 2 |
Uncemented | Number | 13,522 | 17,679 | 31,201 | 503 | 403 | 906 | 297 | 434 | 731 |
| Â | % | 30.4 | 25.5 | 27.4 | 46 | 62.9 | 52.2 | 94.3 | 96.7 | 95.7 |
Hybrid | Number | 9029 | 14,260 | 23,289 | 49 | 25 | 74 | 10 | 8 | 18 |
| Â | % | 20.3 | 20.6 | 20.5 | 4.5 | 3.9 | 4.3 | 3.2 | 1.8 | 2.4 |
Resurfacing | Number | 3130 | 1215 | 4345 | 470 | 178 | 648 | 0 | 0 | 0 |
| Â | % | 7 | 1.8 | 3.8 | 43 | 27.8 | 37.4 | 0 | 0 | 0 |
ASA 1-2 | Number | 36,598 | 57,355 | 93,953 | 1012 | 587 | 1599 | 306 | 438 | 744 |
| Â | % | 82.3 | 82.8 | 82.6 | 92.6 | 91.6 | 92.2 | 97.1 | 97.6 | 97.4 |
ASA 3-5 | Number | 7870 | 11,949 | 19,819 | 81 | 54 | 135 | 9 | 11 | 20 |
| Â | % | 17.7 | 17.2 | 17.4 | 7.4 | 8.4 | 7.8 | 2.9 | 2.4 | 2.6 |
Cup/Head bearing surfaces | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
Ceramic/Ceramic | Number | 6584 | 8161 | 14,745 | 0 | 0 | 0 | 0 | 0 | 0 |
| Â | % | 14.8 | 11.8 | 13 | 0 | 0 | 0 | 0 | 0 | 0 |
Metal/Metal | Number | 165 | 129 | 294 | 0 | 0 | 0 | 315 | 449 | 764 |
| Â | % | 0.4 | 0.2 | 0.3 | 0 | 0 | 0 | 100 | 100 | 100 |
Polyethylene/Ceramic | Number | 4863 | 7070 | 11,933 | 0 | 0 | 0 | 0 | 0 | 0 |
| Â | % | 10.9 | 10.2 | 10.5 | 0 | 0 | 0 | 0 | 0 | 0 |
Polyethylene/Metal | Number | 29,088 | 52,436 | 81,524 | 0 | 0 | 0 | 0 | 0 | 0 |
| Â | % | 65.4 | 75.7 | 71.7 | 0 | 0 | 0 | 0 | 0 | 0 |
Resurfacing/Metal | Number | 318 | 233 | 551 | 534 | 447 | 981 | 0 | 0 | 0 |
| Â | % | 0.7 | 0.3 | 0.5 | 48.9 | 69.7 | 56.6 | 0 | 0 | 0 |
Resurfacing/Resurfacing | Number | 3450 | 1275 | 4725 | 559 | 194 | 753 | 0 | 0 | 0 |
| Â | % | 7.8 | 1.8 | 4.2 | 51.1 | 30.3 | 43.4 | 0 | 0 | 0 |