Abstract

Objective: To study the feasibility and validity of a two-step telephone screening procedure for symptomatic knee and hip osteoarthritis (OA) in the general population.

Method: The screening questionnaire was based on signs and symptoms, previous diagnosis of OA, and validated OA criteria. A random sample of telephone numbers was obtained and, at each number, one individual aged 40 to 75 years was included. A physical examination and knee or hip radiographs were offered when the screen was positive. A sample of individuals with negative screens was also examined. The diagnosis of hip/knee OA was based on the American College of Rheumatology criteria for signs and symptoms and Kellgren-Lawrence radiographic stage 2 or greater. Prevalence rates were estimated with correction for the performance of the screening procedure.

Results: Of 1380 individuals, 479 had positive screens, among whom 109 were evaluated; Symptomatic radiographic OA was found in 50 individuals, at the knee (n=35) or hip (n=20). Corrected prevalence estimates of symptomatic OA were 7.6% [6.4-8.8] for the knee and 5% (3.9-6.1) for the hip. The screening procedure had 87% [95% confidence interval [95%CI], 79-95%] sensitivity, and 92% [95% CI: 91-93] specificity for detecting knee OA and respectively 93% [95% CI: 86-100] and 93% [95% CI: 92-94] for hip OA.

Conclusion: This study establishes the feasibility of a telephone screening for symptomatic knee/hip OA, which could be used for a nationwide prevalence study. Pain and previous OA diagnosis were the best items for detecting symptomatic OA.