2023 American College of Rheumatology/European Alliance of Associations for Rheumatology classification criteria for antiphospholipid syndrome: good for patients or good for papers?

The American College of Rheumatology/European Alliance of Associations for Rheumatology classification criteria for antiphospholipid syndrome (APS) is a new set of robust criteria, including clinical and laboratory criteria, to enhance the identification of patients in clinical studies and laboratory research. Based on a scoring system, patients accruing at least 3 points in the clinical and laboratory domains fulfill the classification criteria for APS. They are meant to define homogeneous patient groups for research. They are not to be used in a clinical setting for diagnosis to identify every patient with APS, where it is essential to include those with an atypical clinical presentation and/or antiphospholipid antibodies laboratory test result. These criteria have provoked a debate among workers in the field. Without nuance, the classification criteria cannot be used for diagnosing APS and may be a potential pitfall for clinicians when no difference is made between "classification" and "diagnostic" criteria. Complementing the American College of Rheumatology/European Alliance of Associations for Rheumatology classification criteria with the recently available International Society on Thrombosis and Haemostasis guidance on laboratory detection and interpretation of antiphospholipid antibodies for diagnosis of APS has added value. It ensures rigorous research that leads to improvement of patient management and optimal clinical care in routine practice.