TABLE III.

Multiple Regression Analysis: Hip Arthroplasty^{* †}

	Primary Total Hip Arthroplasty		Hip Resurfacing		Aseptic Revision Total Hip Arthroplasty
Parameter	Coefficient and Standard Deviation	P Value	Coefficient and Standard Deviation	P Value	Coefficient and Standard Deviation	P Value
Intercept‡	0.898 ± 0.020	<0.0001	0.793 ± 0.044	<0.0001	0.605 ± 0.075	<0.0001
Age	−0.001 ± 0.0002	<0.00001	0.001 ± 0.001	0.199	0.001 ± 0.001	0.485
BMI	−0.002 ± 0.0004	<0.0001	−0.001 ± 0.001	0.585	0.0002 ± 0.002	0.902
CCI	−0.004 ± 0.002	0.056	0.010 ± 0.009	0.304	−0.005 ± 0.010	0.613
Sex (male vs. female)	0.025 ± 0.005	<0.0001	0.020 ± 0.011	0.068	0.045 ± 0.019	0.021
ASA score (3 or 4 vs. 1 or 2)	−0.030 ± 0.006	<0.0001	−0.081 ± 0.023	0.001	−0.020 ± 0.023	0.374
Preoperative EQ-5D index score	−0.812 ± 0.012	<0.0001	−0.860 ± 0.028	<0.0001	−0.771 ± 0.044	<0.0001

^*The outcome variable was defined as the change from the baseline preoperative EQ-5D index score to the 2-year postoperative EQ-5D index score. BMI = body mass index, CCI = Charlson Comorbidity Index, and ASA = American Society of Anesthesiologists.

^†R² = 0.588 for primary total hip arthroplasty, 0.639 for hip resurfacing, and 0.523 for aseptic revision total hip arthroplasty.

^‡The intercept is the expected value when all of the values in the regression model are set to 0.