TABLE 4.

REGRESSION ANALYSIS OF ASSOCIATIONS BETWEEN FREQUENT KNEE PAIN AND SF-12 MENTAL COMPONENT SUMMARY SCORE (N = 2481)

Regression Term	Model 1* (n = 1809)			Model 2† (n = 1344)			Model 3‡ (n = 1344)
	β	SE	P Value	β	SE	P Value	β	SE	P Value
Constant	52.9	0.27	<.0001	38.6	1.76	<.0001	47.7	2.00	<.0001
No knee pain§ (reference)
Frequent unilateral knee painl	−1.0	0.41	.013	−0.48	0.41	.24	0.04	0.35	.91
Frequent bilateral knee pain¶	−2.48	0.41	<.0001	−1.29	0.42	.002	−0.6	0.35	.091
Age				0.18	0.02	<.0001	0.14	0.02	<.0001
Sex (female versus male)				0.52	0.41	.20	0.2	0.34	.41
Race (white versus nonwhite)				−0.05	0.49	.92	−0.17	0.42	.68
Marital status (married versus unmarried/separated)				0.64	0.63	.30	−0.13	0.51	.79
Social support (live single versus live with others)				0.31	0.68	.65	0.33	0.56	.55
Education (high school or less versus some college/graduates)				0.48	0.20	.019	0.17	0.17	.30
Income (< $50K versus > $50K)				2.0	0.47	<.0001	1.0	0.39	.009
Healthcare coverage (yes versus no)				0.59	1.0	.57	−0.72	0.84	.40
Fallen, past 12 mo (yes versus no)							−0.22	0.25	.37
Depressive symptoms (yes versus no)							−14.9	0.52	<.0001
Comorbidity (yes versus no)							−1.25	0.34	.0003
BMI							0.11	0.03	.0016

Abbreviations: BMI, body mass index; SE, standard error; SF-12, Medical Outcomes Study 12-Item Short-From Health Survey.

^*Unadjusted. Adjusted R² = 0.02.

^†Adjusted for age, sex, race, education, marital status, social support, income, and healthcare coverage. Adjusted R² = 0.08.

^‡Additionally adjusted for BMI, falls, depression, and comorbidities. Adjusted R² = 0.38.

^§No pain in either knee.

^lFrequent pain in one knee and no pain in other knee.

^¶Frequent pain in both knees.