small airway indicators, which was lacking in previous studies [1][2][3]. Pediatricians should focus on changes in lung function as well as the clinical control of asthma. We also found that BMI, onset at 1-3 y of age, a longer time interval of delayed diagnosis, and a high allergy to dust mites were closely related to FEV1 decline. In particular, we have previously identified the impact of the delayed diagnosis on lung function [4], so the early diagnosis of asthma needs to be taken seriously.Funding This study was funded by the Jinan Key Laboratory of Pediatric Respiratory diseases (Xiang Ma is the PI), Clinical Science and Technology Innovation Plan in Jinan (202134067), Clinical Science and Technology Innovation Plan in Jinan ( 202225022), and Shandong Provincial Natural Science Program (ZR2021MH147). The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.
DeclarationsConflict of Interest None.Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.