Table 1.
Baseline clinical and utilization characteristics
| Characteristic | Group; no. (%)* | ||
|---|---|---|---|
|
| |||
| Knee arthroplasty n = 233 281 |
Total hip replacement n = 154 381 |
Lumbar fusion n = 16 363 |
|
| Age at index date; mean ± SD and median [IQR] | 68.66 ± 9.44 | 67.09 ± 11.94 | 58.14 ± 14.68 |
| 69 [62–76] | 69 [60–76] | 60 [47–70] | |
|
| |||
| Female sex | 145 538 (62.4) | 86 754 (56.2) | 9258 (56.6) |
|
| |||
| Charlson Comorbidity Index score = 0 | 151 720 (65.0) | 107 434 (69.6) | 11 871 (72.5) |
|
| |||
| Neighbourhood income quintile | |||
|
| |||
| 1 | 42 891 (18.4) | 25 899 (16.8) | 2918 (17.8) |
|
| |||
| 2 | 48 177 (20.7) | 29 845 (19.3) | 3237 (19.8) |
|
| |||
| 3 | 47 205 (20.2) | 30 112 (19.5) | 3207 (19.6) |
|
| |||
| 4 | 46 624 (20.0) | 31 569 (20.4) | 3384 (20.7) |
|
| |||
| 5 | 47 431 (20.3) | 36 272 (23.5) | 3546 (21.7) |
|
| |||
| Missing | 953 (0.4) | 684 (0.4) | 71 (0.4%) |
|
| |||
| Rural | |||
|
| |||
| No | 191 610 (82.1) | 127 249 (82.4) | 13 656 (83.5) |
|
| |||
| Yes | 41 462 (17.8) | 27 001 (17.5) | 2678 (16.4) |
|
| |||
| Missing | 209 (0.1) | 131 (0.1) | 29 (0.2) |
|
| |||
| 2008 Rurality Index for Ontario; mean ± SD and median [IQR] | 13.73 ± 19.08 | 13.35 ± 18.71 | 13.17 ± 18.71 |
| 4 [0–24] | 4 [0–24] | 4 [0–22] | |
|
| |||
| OHIP provider (specialty) | |||
|
| |||
| General | ≤ 5 (0.0)† | 0 (0.0) | 0 (0.0) |
|
| |||
| Neuro | 0 (0.0) | 0 (0.0) | 3004 (18.4) |
|
| |||
| Ortho | 233 235 (100.0) | 154 334 (100.0) | 13 352 (81.6) |
|
| |||
| Other | 41–45 (0.0)† | 47 (0.0) | 7 (0.0) |
|
| |||
| Hospital type | |||
|
| |||
| Teaching | 178 603 (76.6) | 108 259 (70.1) | 9547 (58.3) |
|
| |||
| Nonteaching | 54 678 (23.4) | 46 121 (29.9) | 6816 (41.7) |
|
| |||
| Missing | 0 (0.0) | ≤ 5 (0.0)‡ | 0 (0.0) |
|
| |||
| Hospital size | |||
|
| |||
| Missing | 554 (0.2) | 156 (0.1) | 6 (0.0) |
|
| |||
| Large | 118 233 (50.7) | 90 025 (58.3) | 12 792 (78.2) |
|
| |||
| Small | 114 494 (49.1) | 64 200 (41.6) | 3565 (21.8) |
|
| |||
| Hospital rurality | |||
|
| |||
| Yes | 41 496 (17.8) | 27 051 (17.5) | 2682 (16.4) |
|
| |||
| No | 191 578 (82.1) | 127 199 (82.4) | 13 657 (83.5) |
|
| |||
| Missing | 207 (0.1) | 131 (0.1) | 24 (0.1) |
|
| |||
| No. of OHIP claim days 1 yr earlier; mean ± SD and median [IQR] | 37.78 ± 23.78 | 34.98 ± 25.06 | 40.97 ± 26.26 |
| 33 [22–47] | 29 [19–44] | 35 [24–51] | |
|
| |||
| Yes† | 41 496 (17.8) | 27 051 (17.5) | 2,682 (16.4) |
|
| |||
| No. of CIHI claim days 1 yr earlier; mean ± SD and median [IQR] 1.50 ± 0.92 | 1.56 ± 1.06 | 1.53 ± 0.98 | |
| 1 [1–2] | 1 [1–2] | 1 [1–2] | |
CIHI = Canadian Institute for Health Information; IQR = interquartile range; OHIP = Ontario Health Insurance Plan; SD = standard deviation.
*
Unless indicated otherwise.
†
No. (%) of patients with any OHIP claim within 1 yr of index date.
‡
Cell sizes with < 5 cases were suppressed in concordance with ICES reidentification risk policy.