Research Article

Evidence-Based Cutoff Threshold Values from Receiver Operating Characteristic Curve Analysis for Knee Osteoarthritis in the 50-Year-Old Korean Population: Analysis of Big Data from the National Health Insurance Sharing Service

Figure 4

Graph of the ROC curve for the 50–59-year-old Korean population with knee OA. ROC curve analysis of ELD_LLFX_SEC (s) provided the optimal threshold value of 8.25 s, with area under the curve value of 0.861, sensitivity of 80%, and specificity of 100% (). ROC, receiver operating characteristic; OA, osteoarthritis; ELD_LLFX_SEC, time in seconds for standing up from a chair, walking 3 m, and returning to the same chair.