[Interpretation of joint statement from GOLD/GLI regarding the use of spirometry to define airflow obstruction and...

Chronic obstructive pulmonary disease(COPD) remains a leading cause of mortality worldwide, and spirometry is the essential objective test for identifying airflow obstruction and confirming COPD in the appropriate clinical context. In 2026, the Global Initiative for Chronic Obstructive Lung Disease (GOLD) and the Global Lung Function Initiative(GLI) published a joint statement on the use of spirometry to define airflow obstruction and diagnose COPD. This statement reframes the long-standing debate between the fixed FEV₁/FVC ratio and the lower limit of normal(LLN), emphasizing that these criteria should not be viewed simply as competing definitions, but as tools serving different clinical and epidemiological purposes.GOLD continues to recommend a fixed post-bronchodilator FEV₁/FVC ratio of <0.70 to confirm persistent airflow obstruction in symptomatic individuals with relevant exposures, whereas GLI supports using the LLN to identify physiological airflow obstruction across populations, particularly to mitigate age-related misclassification. The joint statement further highlights that major global challenges extend beyond threshold selection to include the underuse of spirometry, variable test quality, and the interpretation of spirometric results without sufficient clinical context. Furthermore, spirometry alone is insufficient for diagnosing COPD; however, normal spirometric findings from technically acceptable tests can help exclude COPD. Results near diagnostic thresholds warrant repeat testing or further clinical evaluation.The statement also supports transitioning to the 2022 GLI race-neutral reference equations while cautioning that predicted values and severity classifications require careful interpretation across diverse populations. Regarding severity grading, both GOLD percent-predicted thresholds and ATS/ERS z-score classifications possess inherent limitations. Consequently, physiological impairment should be evaluated alongside symptoms, exacerbation risk, comorbidities, imaging findings, and clinically meaningful outcomes.This review summarizes the main viewpoints of the GOLD-GLI joint statement, focusing on the practical differences between the fixed ratio and LLN, barriers to spirometry implementation, quality assurance, reference equations, and severity grading. In addition, we integrate recent Chinese community-based and real-world evidence, including simplified pre-bronchodilator spirometry for population screening, portable spirometry in primary care, and artificial intelligence-assisted spirometry interpretation. By combining updated international consensus with local evidence and emerging technologies, this article provides a practical reference for standardizing COPD diagnosis and optimizing screening strategies in China.