The investigators have created an interactive knee osteoarthritis (OA) risk calculator that estimates a user's risk of developing symptomatic knee OA as well as the user's risk for undergoing a total knee replacement (TKR) within their lifetime. To test the impact of the calculator, the investigators recruited OA-free subjects from Amazon's Mechanical Turk. Participants were randomized to either access general information about OA or use the risk calculator in addition to accessing general OA information. The investigators hypothesized that participants randomized to the risk calculator arm would have more accurate perception of their knee OA risk and would have increased willingness to change risky behavior compared to the general OA information group.