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

We aimed to investigate the characteristics of patients with osteoarthritis (OA), using the data of all Koreans registered in the National Health Insurance Sharing Service Database (NHISS DB), and to provide ideal alternative cutof thresholds for alleviating OA symptoms. Patients with OA (codes M17 and M17.1?M17.9 in the Korean Standard Classifcation of Disease and Causes of Death) were analyzed using SAS sofware. Optimal cutof thresholds were determined using receiver operating characteristic curve analysis. Te 50-year age group was the most OA pathogenic group (among 40∼70 years, n = 2088). All exercise types afected the change of body mass index (p < 0.05) and the sex diference in blood pressure (BP) (p < 0.01). All types of exercise positively afected the loss of waist circumference and the balance test (standing time on one leg in seconds) (p < 0.01). Te cutof threshold for the time in seconds from standing up from a chair to walking 3 m and returning to the same chair was 8.25 (80% sensitivity and 100% specifcity). By using the exercise modalities, categorized multiple variables, and the cutof threshold, an optimal alternative exercise program can be designed for alleviating OA symptoms in the 50-year age group.