Ratio of surgical rate with post-secondary education to rate with lower education level. Hanchate: Relative to less than high school education. U.S. population-based study age ≥ 47. Adjusted for age, gender, race, comorbidities, functional limitations, income, wealth, insurance type, employment, BMI ≥ 25. *Refers to respondents with an arthritis-related visit to the doctor in the past two years at baseline; other result refers to all respondents . Hawker: Relative to less than high school education. Sample from two areas in Ontario, Canada. Adjusting for WOMAC, SF-36 General Health, age . Steel: Relative to less than college education. U.S. population-based study age ≥ 60. Adjusting for covariates age, gender, wealth, employment, BMI ≥ 30, seen doctor ≥2 times in past 2 years, comorbidity .