CASPAR Criteria for Psoriatic Arthritis
Provides classification criteria for psoriatic arthritis.
Result:
Why did you develop the CASPAR Criteria for PsA? Was there a particular clinical experience or patient encounter that inspired you to create this tool for clinicians?
There were multiple published classification criteria for PsA that seemed to be in competition, which made standardized case-definition for inclusion in clinical trials problematic. So the motivation for CASPAR was to bring many groups together to get consensus on the most accurate criteria. As it happened, the data we collected led to new criteria being developed that were more accurate than any of the existing criteria.
What pearls, pitfalls and/or tips do you have for users of the CASPAR Criteria for PsA? Do you know of cases when it has been applied, interpreted, or used inappropriately?
The most difficult aspect of the CASPAR criteria is the mandatory feature of inflammatory articular, entheseal, or axial disease. This feature not precisely defined and is more or less left to expert judgment. This often means that a rheumatologist is required to help apply the criteria. It is important to remember that these criteria were designed for case-definition for inclusion in clinical trials, and not for diagnosis in everyday practice (although the CASPAR items can be useful as a reminder of key features of PsA).
What recommendations do you have for doctors once they have applied the CASPAR Criteria for PsA? Are there any adjustments or updates you would make to the score based on new data or practice changes?
The CASPAR criteria have actually been shown to be remarkably robust in several different patient populations. PsA continues to be difficult to diagnose because of the absence of a pathogenic and specific biomarker. If such a biomarker is identified, the CASPAR criteria will need to be revised.
How do you use the CASPAR Criteria for PsA in your own clinical practice? Can you give an example of a scenario in which you use it?
I do not use the CASPAR criteria in clinical practice. It is designed for clinical research studies.
William J. Taylor, MBChB, PhD, is an associate professor of rheumatology at Wakefield Hospital as well as the University of Otago in Wellington, New Zealand. He is also president of the New Zealand Rehabilitation Association. Dr. Taylor’s research focuses primarily on osteoporosis, adult rheumatology, and gout.
