Table 6.
Adjusted comparison of acute hospital length of stay after total hip or knee replacement, by patient and hospital characteristic and surgeon procedure volume
| Characteristic | Adjusted* rate ratio (95% CI) | |
|---|---|---|
| Hip | Knee | |
| Patient age (yr) | 1.01† (1.01–1.01) | 1.01† (1.01–1.01) |
| Patient sex (male v. female) | 0.96† (0.94–0.99) | 0.98 (0.96–1.00) |
| Patient comorbidity (Charlson index v. missing or 0) | ||
| 1 | 1.19† (1.11–1.28) | 1.09† (1.04–1.15) |
| ≥ 2 | 1.38† (1.22–1.56) | 1.17† (1.11–1.23) |
| Patient’s arthritis type (rheumatoid v. other) | 1.01 (0.98–1.04) | 1.01 (0.99–1.03) |
| Patient discharge disposition (rehabilitation unit or facility v. other) | 0.87† (0.78–0.97) | 0.85† (0.77–0.94) |
| Hospital teaching status (teaching v. other) | 1.17 (0.96–1.42) | 1.05 (0.90–1.22) |
| Hospital procedure volume (mean no. per yr v. hip 10–110, knee 10–130) | ||
| 111–150, 131–180 | 0.97 (0.85–1.11) | 0.99 (0.88–1.12) |
| 151–225, 181–270 | 0.93 (0.74–1.17) | 0.94 (0.78–1.15) |
| > 225, > 270 | 0.79 (0.61–1.00) | 1.03 (0.78–1.35) |
| Surgeon procedure volume (mean no. per yr v. hip 2–25, knee 2–35) | ||
| 26–40, 36–50 | 0.93† (0.89–0.98) | 0.98 (0.94–1.02) |
| 41–60, 51–70 | 0.93† (0.88–0.98) | 0.97 (0.94–1.01) |
| > 60, > 70 | 0.89† (0.81–0.98) | 0.93† (0.88–0.98) |
CI = confidence interval.
*
Adjusted for patient age, sex, comorbidity and arthritis type, hospital teaching status, hospital procedure volume, and surgeon procedure volume.
†
Significant at p < 0.05.