The American College of Rheumatology criteria for the classification of systemic lupus erythematosus: Strengths, weaknesses, and opportunities for improvement

The American College of Rheumatology classification criteria were developed to operationalize the definition of systemic lupus erythematosus (SLE) to allow comparison of clinical research from different centers, but also serv e to facilitate education and to guide clinical practice. The classificatio n criteria have been critical to research, but should be viewed as a tempor ary step until improved understanding of the pathogenesis of SLE emerges. C riteria have inherent limitations, including bias towards more severe and l onger duration disease, equal weighting of features that vary in clinical s ignificance, and exclusion of patients with SLE from research because they do not meet criteria. For some SLE research questions, it may be appropriat e to include patients diagnosed with SLE who do not meet criteria, if these patients' manifestations and criteria are documented explicitly. SLE disea se activity, cumulative organ damage, disease duration, criteria ever met, and criteria met at time of enrollment are important data that should be pr esented in clinical studies of SLE regardless of the number of criteria met . The criteria should be reevaluated periodically, utilizing patients and c ontrols with a range of diseases and disease severity. A simplified weighti ng system may more accurately reflect clinical practice.