A62-08 Diagnostic Accuracy and Clinical Agreement Between the Global Lung Function Initiative 2012 (GLI-2012) and 2022 (GLI-2022) Reference Equations in Pediatric Spirometry at High Altitude in Bogotá, Colombia

Background The Global Lung Function Initiative (GLI) introduced race-neutral reference equations (GLI-2022) to replace race-based groupings from GLI-2012. Despite broad endorsement, their diagnostic performance in Latin American pediatric populations living at high altitude remains insufficiently validated. We assessed whether GLI-2022 preserves diagnostic accuracy and agreement versus GLI-2012 (Caucasian and Mixed) in children with asthma in Bogotá, Colombia (2,640 m above sea level). Methods Cross-sectional study including 70 children aged 6-17 years with physician-diagnosed, clinically stable asthma and no recent respiratory infection. Spirometry followed American Thoracic Society and European Respiratory Society (ATS/ERS) 2019 standards. Z-scores for forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC were computed under GLI-2012 Caucasian (C), GLI-2012 Mixed (M), and GLI-2022 Neutral (N). Spearman correlation quantified associations between z-scores across equations. Diagnostic agreement for obstruction (Lower Limit of Normal or LLN defined as FEV1/FVC z < −1.645) was assessed with Cohen’s kappa and McNemar tests. Results Correlations between equations were near-perfect for FEV1/FVC (ρ N vs C = 0.995; N vs M = 0.994; C vs M = 0.999; all p < 0.001). Obstruction prevalence was identical with GLI-2012C and GLI-2022N (17.1%) but higher with GLI-2012M (22.9%; p < 0.01). Two children classified as obstructive by GLI-2012C were reclassified as normal under GLI-2022N. Diagnostic agreement was almost perfect for N vs C (κ = 0.97) and substantial for N vs M (κ = 0.89). Conclusion In pediatric spirometry at high altitude in Colombia, GLI-2022 maintains excellent diagnostic accuracy and agreement with GLI-2012C while avoiding the overestimation observed with GLI-2012M. These results confirm that race-neutral equations can be reliably applied in admixed, high-altitude populations, providing more equitable and physiologically appropriate interpretation. These findings support transitioning laboratories to GLI-2022 and motivate prospective studies to test predictive validity for clinical outcomes. Funding None declared. Conflicts of interest The authors declare no conflicts of interest.Accuracy: The submitting author is responsible for the accuracy of the abstract. Abbreviations are defined at first mention (FEV1, FVC, LLN).