FAQs (Data Related) Additional Case Definition
- Why was the arthritis case definition changed in 2002?
- How is the current case definition of doctor-diagnosed (used since 2002) different from the old case definition (used 1996–2001)?
CDC, partners, and outside experts agreed to use a new definition, starting in 2002. The reasons for this were many.
First, the questions used to determine both doctor-diagnosed arthritis and chronic joint symptoms were changed. A summary of the BRFSS arthritis questions from 1996 on can be found in the following document.
Because of the change in the questions and the results of validation studies, a new case definition appeared in order. Using doctor-diagnosed arthritis as the definition:
- Is likely to be more valid than the old definition, in identifying those most likely to have arthritis.
- Is more compatible with surveillance definitions for other health conditions.
- Identifies those most likely to be affected by arthritis, and thus more likely to be more receptive to our interventions.
- Would be easier to adapt to a smaller BRFSS survey being considered for the future, because it requires only one question.
From 1996 to 2001, the case definition included those with doctor-diagnosed arthritis and/or those with chronic joint symptoms and labeled them “arthritis or chronic joint symptoms.”
Since 2002, CDC, partners, and outside experts have agreed on a new case definition of simply “doctor-diagnosed arthritis.”
As an interim step from 2002 to 2007 people with chronic joint symptoms but no doctor-diagnosed arthritis, were put into a category called “possible arthritis.” CDC advised analysts to keep estimates for “possible arthritis” separate from estimates for doctor-diagnosed arthritis.
In 2009, the 2 questions on chronic joint symptoms will be dropped and replaced with other questions that address the impact of arthritis.
Get email updates
To receive email updates about this page, enter your email address:
What Do You Think
of This Site?
- Arthritis Program
4770 Buford Hwy NE
Atlanta, GA 30341-3724
- Phone: 770.488.5464