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

CharacteristicAdjusted* rate ratio (95% CI)
HipKnee
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)
 11.19 (1.11–1.28)1.09 (1.04–1.15)
 ≥ 21.38 (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, 131–1800.97 (0.85–1.11)0.99 (0.88–1.12)
 151–225, 181–2700.93 (0.74–1.17)0.94 (0.78–1.15)
 > 225, > 2700.79 (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, 36–500.93 (0.89–0.98)0.98 (0.94–1.02)
 41–60, 51–700.93 (0.88–0.98)0.97 (0.94–1.01)
 > 60, > 700.89 (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.