Completed Projects Managed Care
Validation of Self-Reported Arthritis Case Definitions in a Managed Care Setting
Task Order 200-95-0953-51
The purpose of this project was to validate the case definition by comparing results of the phone interview with a physical examination for arthritis.Because many persons with arthritis do not see a health care provider regularly for their symptoms, measuring the full burden of arthritis relies on self-reported data. The Behavioral Risk Factor Surveillance System (BRFSS), an ongoing telephone survey, is being used by states and the CDC Arthritis Program to measure the burden of arthritis. For the purpose of measuring burden, a “case of arthritis” is identified by a self-report of chronic joint symptoms (CJS) and/or doctor-diagnosed arthritis (DDx). Unfortunately, the accuracy of this case definition and its implications has not been determined, i.e., do persons meeting the case definition have clinically verifiable arthritis?
- For those aged 45 to 64 years, the weighted sensitivity of the case definition in this sample was 77.4% and the weighted specificity was 58.8%; for those aged 65 and older, the sensitivity was 83.6% and specificity 70.6%.
- CJS+ had higher sensitivity and lower specificity than DDx+ in the younger age group; CJS+ and DDx+ was more comparable in the older age group.
- Although the case definition based on self-reported CJS and/or DDx appeared sensitive in identifying arthritis, specificity was lower than desirable for those under age 65 years. Better methods of ascertaining arthritis by self-report are needed. Until then, a change in the surveillance case definition for arthritis appears warranted.
Abstracts, Publications, Presentations
Yood RA, Sacks JJ, Harrold LR, Emani S, Gurwitz JH, Helmick CG. Validation of a telephone survey surveillance case definition of arthritis: Preliminary results. Arthritis & Rheumatism 2003;48(9, supplement):S393.
Sacks JJ, Harrold LR, Helmick CG, Gurwitz JH, Emani S, Yood RA. Validation of a surveillance case definition for arthritis. J Rheumatol, 2005;32(2):340–347.
Robert A. Yood, M.D.
425 North Lake Ave.
Worcester, MA 01605