TABLE V.

Multiple Regression Analysis: Knee Arthroplasty^*†

	Primary Total Knee Arthroplasty		Unicompartmental Knee Arthroplasty		Aseptic Revision Total Knee Arthroplasty
Parameter	Coefficient and Standard Deviation	P Value	Coefficient and Standard Deviation	P Value	Coefficient and Standard Deviation	P Value
Intercept‡	0.749 ± 0.026	<0.0001	0.695 ± 0.101	<0.0001	0.494 ± 0.096	<0.0001
Age	−0.001 ± 0.0003	0.051	0.000 ± 0.001	0.986	0.003 ± 0.001	0.002
BMI	−0.001 ± 0.0004	0.008	0.000 ± 0.002	0.843	−0.004 ± 0.002	0.047
CCI	−0.006 ± 0.003	0.023	0.012 ± 0.012	0.341	−0.020 ± 0.013	0.115
Sex (male vs. female)	0.027 ± 0.005	<0.0001	0.032 ± 0.021	0.124	0.034 ± 0.022	0.126
ASA score (3 or 4 vs. 1 or 2)	−0.044 ± 0.006	<0.0001	−0.022 ± 0.029	0.440	−0.097 ± 0.025	0.0001
Preoperative EQ-5D index score	−0.753 ± 0.015	<0.0001	−0.802 ± 0.070	<0.0001	−0.718 ± 0.056	<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 = 0.446 for primary total knee arthroplasty, 0.467 for unicompartmental knee arthroplasty, and 0.454 for aseptic revision total knee arthroplasty.

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