[Standardization of spirometry updated in China and international: comparison and interpretation of the key updates]

Standardization of spirometry was jointly updated by the American Thoracic Society (ATS) and the European Respiratory Society (ERS) in 2019. Similar technical standards for spirometry recommended by the Chinese Thoracic Society (CTS) and/or the Chinese Association of Chest Physicians (CACP) are widely used in China. We compared the key similarities and differences of these recommendations and interpreted the key updates. The ATS/ERS 2019 updates expanded the scope of indications for spirometry and recommended the contraindications based on the pathophysiological perspective, while contraindications recommended by the CTS were based on the severity of contraindications. ISO 26782∶2009 standards were applied by the ATS/ERS 2019 to evaluate the performance quality (reliance for accuracy, repeatability, etc.) of spirometers, while standards adopted 24/26 waves suggested by the ATS 1994 was used by the CTS. The ATS/ERS 2019 also included the performance quality control criteria for 3-L calibration syringe, operator training and attainment and maintenance of competency, grade"U", system warning messages, instructions to patients, and standardized operator comments. Some of these criteria in the CTS were not explained in detail. However, the CTS/CACP emphasized that the spirometry record should report the indices of forced inspiratory phase and small airway function, those are not clearly required in the ATS/ERS 2019. In comparison, the ATS/ERS 2019 has stricter criteria for FEV₁ and FVC acceptability than the CTS and more detailed explanations. Those outstanding parts are worth referencing for the updated version of the CTS in the future, while the criteria that combine our own conditions need to be retained and popularized.