PT - JOURNAL ARTICLE AU - Quanjer, P.H. AU - Stanojevic, S. AU - Stocks, J. AU - Hall, G.L. AU - Prasad, K.V.V. AU - Cole, T.J. AU - Rosenthal, M. AU - Perez-Padilla, R. AU - Hankinson, J.L. AU - Falaschetti, E. AU - Golshan, M. AU - Brunekreef, B. AU - Al-Rawas, O. AU - Kühr, J. AU - Trabelsi, Y. AU - Ip, M.S.M. TI - Changes in the FEV<sub>1</sub>/FVC ratio during childhood and adolescence: an intercontinental study AID - 10.1183/09031936.00164109 DP - 2010 Dec 01 TA - European Respiratory Journal PG - 1391--1399 VI - 36 IP - 6 4099 - https://publications.ersnet.org//content/36/6/1391.short 4100 - https://publications.ersnet.org//content/36/6/1391.full SO - Eur Respir J2010 Dec 01; 36 AB - In children, the ratio of forced expiratory volume in 1 s (FEV1) to forced vital capacity (FVC) is reportedly constant or falls linearly with age, whereas the ratio of residual volume (RV) to total lung capacity (TLC) remains constant. This seems counter-intuitive given the changes in airway properties, body proportions, thoracic shape and respiratory muscle function that occur during growth. The age dependence of lung volumes, FEV1/FVC and RV/TLC were studied in children worldwide. Spirometric data were available for 22,412 healthy youths (51.4% male) aged 4–20 yrs from 15 centres, and RV and TLC data for 2,253 youths (56.7% male) from four centres; three sets included sitting height (SH). Data were fitted as a function of age, height and SH. In childhood, FVC outgrows TLC and FEV1, leading to falls in FEV1/FVC and RV/TLC; these trends are reversed in adolescence. Taking into account SH materially reduces differences in pulmonary function within and between ethnic groups. The highest FEV1/FVC ratios occur in those shortest for their age. When interpreting lung function test results, the changing pattern in FEV1/FVC and RV/TLC should be considered. Prediction equations for children and adolescents should take into account sex, height, age, ethnic group, and, ideally, also SH.