Objective: The preliminary classification criteria for antiphospholipid syndrome (APS), or the Sapporo criteria, are widely used for the inclusion of patients with APS into clinical studies. Revised Sapporo criteria have been proposed as an improved criteria set. Whether these criteria sets fulfill the current standards of measurement science are unknown. The purpose of this study was (1) to evaluate the developmental methodology and measurement properties of the Sapporo and the revised Sapporo criteria for use in clinical trials; and (2) to evaluate if the revised Sapporo criteria provide added value over the Sapporo criteria.
Methods: A computer search for articles describing use of the Sapporo and the revised Sapporo criteria was performed. Item generation, item reduction, sensibility, validity, and reliability of the criteria were evaluated.
Results: The Sapporo criteria set has incremental face and content validity over its predecessors. However, through separation of anti-ss2-glycoprotein I antibodies as a sub-item, the specification of a wider time interval between serologic testing, the specification of a time interval between serology and clinical manifestations, and specification of definitions for clinical manifestations and laboratory titer thresholds, the revised Sapporo criteria set has incremental face and content validity over the Sapporo criteria. The complexity of the criteria, diagnostic tests, and immunologic tests limits their feasibility. The reliability of each criterion is unknown. The discriminative capacity of the Sapporo criteria is good, with sensitivity, specificity, and positive and negative predictive values of 0.71, 0.98, 0.95, and 0.88, respectively, compared to patients with systemic lupus erythematosus. The discriminative capacity of the revised Sapporo criteria is unknown.
Conclusion: The revised Sapporo criteria set has incremental face and content validity compared its predecessors. Reliability testing of each criterion is needed before these criteria can be confidently used in multicenter APS trials. Discriminatory testing of the revised Sapporo criteria is required.