Table 1.

Characteristics of African Americans and Whites participating in accelerometer monitoring with and at risk for radiographic knee osteoarthritis (RKOA)

Characteristics	With RKOA (n=1142)		Atrisk for RKOA (n=747)
	African American	White	African American	White
N	206	936	80	667
Socio-demographic Factors
Age in years: mean (SD)	62.9 (14.2)	67.2 (13.8)	61.7 (15.5)	63.8 (15.0)
Gender Men %	32.3	44.7	30.0	42.9
Women %	67.7	55.3	70.1	57.1
Income 0–$50K %	54.7	32.2	68.5	30.7
≥$50K %	34.6	63.5	28.3	66.5
Unknown %	10.7	4.3	3.2	2.8
Education years 0–12 %	30.7	13.9	21.9	8.8
13+ %	63.6	86.1	78.1	90.7
Missing %	5.7	0.0	0.0	0.4
Health Factors
Presence of comorbidity %	48.5	38.0	69.7	36.8
BMI: mean (SD)	32.0 (8.8)	28.8 (7.4)	28.8 (8.9)	27.4 (7.1)
Normal† %	6.2	22.5	24.8	32.0
Overweight†† %	29.3	40.2	27.8	42.2
Obese††† %	64.5	37.4	47.4	25.8
High depressive symptoms#	22.4	10.1	40.8	15.6
Knee pain severity: mean## (SD)	5.8 (8.4)	3.0 (4.9)	5.6 (8.1)	2.2 (5.0)

^†Normal body mass index (BMI): 18.5–24.9 (includes 6 participants with BMI 17.2–18.4),

^††Overweight BMI: 25.0–29.9,

^†††Obese BMI: ≥ 30.

^#High depressive symptoms were defined as CESD≥ 16.

^##Person-level knee pain score was calculated using the maximum value of WOMAC knee pain scores of the two knees; a higher number represents worse symptoms.