Baseline demographics and clinical characteristics
| Feature | Frequency, n (%) | Mean±SD | Median (IQR) | |
| n participants | 947 | |||
| Sex: | ||||
| Female | 551 (58.2) | |||
| Race: | ||||
| American Indian/Alaskan native | 3 (0.3) | |||
| Asian | 8 (0.8) | |||
| Black/African American | 109 (11.5) | |||
| Don’t know/refused | 1 (0.1) | |||
| More than one race | 7 (0.7) | |||
| Other | 11 (1.2) | |||
| White/Caucasian | 808 (85.3) | |||
| Clinic site: | ||||
| University of Iowa | 609 (64.3) | |||
| Cohort: | ||||
| New | 768 (81.1) | |||
| Previous injury/surgery: | ||||
| Yes | 178 (18.8) | |||
| Medial tibiofemoral cartilage damage: | ||||
| Present | 371 (39.2) | |||
| Age (years) | 59.2±8.3 | 59.0 (53.0 to 65.0) | ||
| Body mass index (kg/m2) | 27.8±4.8 | 27.2 (24.3 to 30.8) | ||
| CES-D (/60) | 5.8±6.5 | 3.0 (1.0 to 9.0) | ||
| Hip-knee-ankle alignment (degrees, negative values indicate varus alignment) | −1.4±2.7 | −1.3 (−3.2 to 0.20) | ||
| Study knee | Contralateral | |||
| Pain during walking*: | ||||
| None | 751 (79.3%) | 754 (79.6%) | ||
| Mild | 165 (17.4%) | 161 (17.0%) | ||
| Moderate or higher | 31 (3.3%) | 32 (3.4%) | ||
| Kellgren-Lawrence Grade (KLG): | ||||
| KLG=0 | 582 (61.5%) | 587 (62.0%) | ||
| KLG=1 | 269 (28.4%) | 248 (26.2%) | ||
| KLG=2 | 96 (10.1%) | 112 (11.8%) | ||
*Extracted from the first question of the Western Ontario and McMaster Universities Osteoarthritis Index.
CES-D, Center for Epidemiologic Studies Depression Scale.