Use of provider global assessment rather than physician's global assessment cheapens the value of disease activity measures: Comment on the article by Anderson et al


  • John A. Goldman MD, MACR, FACP, CCD

    1. Atlanta, GA
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    • Dr. Goldman has received consultant fees, speaking fees, and/or honoraria (less than $10,000 each) from Atlanta Center for Clinical Research and UCB and (more than $10,000 each) from Amgen and Pfizer, owns stock or stock options in Bristol-Myers Squibb, and has served as an expert witness in cases involving patients with polymyositis and juvenile idiopathic arthritis.

Use of Provider Global Assessment Rather Than Physician's Global Assessment Cheapens the Value of Disease Activity Measures: Comment on the Article by Anderson et al

To the Editor:

The article by Anderson et al published in a recent issue of Arthritis Care & Research has changed the disease activity measure physician's global assessment of disease activity (PGA) to provider global assessment of disease activity (PrGA). I vehemently disagree with this decision by the committee. The physician filter to evaluate the activity of rheumatoid arthritis is crucial to the application of disease activity measures. An article by Harrington (2) points out that disease activity measures can be affected by a variety of comorbidities: osteoarthritis, back pain, soft tissue rheumatism, and/or prior joint damage. When Harrington compared the global arthritis score and PGA, these were concordant for active or inactive disease in 126 (68%) of 185 patients and were discordant in 59 (32%). There is no replacement for a sagacious rheumatologist to evaluate the role of a disease activity measure in the care of rheumatoid arthritis. A health care provider is not the same as a physician, and cheapening the PGA to a PrGA gives way to the incorrect application of the disease activity measure.

Anderson et al state “The 14 measures were then grouped (Disease Activity Score [DAS]/DAS with 28-joint counts [DAS28], Simplified Disease Activity Index [SDAI]/Clinical Disease Activity Index [CDAI], Patient Activity Scale [PAS] scores, Routine Assessment of Patient Index Data [RAPID] scores, Rheumatoid Arthritis Disease Activity Index 5, Chronic Arthritis Systemic Index, and patient global assessment of disease activity [PtGA]/provider global assessment of disease activity [PrGA]) and incorporated into a survey sent to practicing rheumatologists (n = 4,368); 335 recipients (7.7%) completed the survey.” Were these rheumatologists asked whether PGA would be better called PrGA?

This article is an ambitious attempt to look at disease activity measures, and I approve of the authors' attempt, but not necessarily their conclusions. I do not approve of the cheapening of the PGA; if you want to do a PGA, go to medical school.

John A. Goldman MD, MACR, FACP, CCD*, * Atlanta, GA.