3.2 Descriptive Statistics
The mean age of all hip patients included in analyses was 58.3 (standard deviation (SD) = 10.0) while the mean age among all knee patients was 59.2 (SD = 9.6). The majority of both patients with hip osteoarthritis or knee osteoarthritis were female (54.4% and 64.2%, respectively) and white (81.7% of knee patients and 84.1% of hip patients). Just over half of both the knee (53.1%) and hip (56%) cohorts were comprised of patients who had completed some college or had graduated from college. There was also a similar proportion of Medicare-insured patients across the two cohorts (36.8% of knee patients and 37.1% of hip patients). Roughly 20% of both hip and knee osteoarthritis patients reported that they were close to a decision after viewing decision aids, while just over half of both hip and knee patients reported that they had made a decision about their treatment choice (58.6% and 53.8% for hip and knee patients, respectively). Full descriptive statistics are reported in Table 1.