DIFFERENCES IN LUNG-FUNCTION AND CHEST DIMENSIONS IN SCHOOL-AGE GIRLSAND BOYS

The present analysis was undertaken to find out whether differences in the performance of the lungs of boys and girls of the same height are explicable by differences in thoracic size. We measured forced vital capacity (FVC), peak expiratory flow (PEF) and forced expiratory flows (FEFs), when 50% and 75% of FVC had been exhaled (FEF(50), FEF(75)), and Standing height, chest width and depth and biacromial diameter in 1187 schoolchildren aged 6-18 years. Thoracic dimensions were usually greater in boys than in girls of the same height, except for the heigh t range of 150.0-164.9 cm. For this height range, the pulmonary functi on variables (PEF, FEF(50), FEF(75) and PEF/FVC) were significantly hi gher in girls, and for FVC almost as high as the male values. For FEF( 50)/FVC and FEF(75)/FVC, the female values were larger over the whole height range (115.0-184.9 cm), but even for these parameters the diffe rences were greatest for the height range 150.0-164.9 cm. In conclusio n, very similar growth patterns of lung function and thoracic paramete rs can suggest that differences in the lung function parameters of boy s and girls of the same height may be explained by differences in the thorax size.