Spirometric values for normal Perth children aged six to twelve years.

The purpose of this study was to construct tables and nomograms of spirometric norms for Perth children aged between six and 12 years. These norms were to be based on anthropometric measurements and age. A sample of 623 children was tested of which 556 were analysed and comprised 289 boys and 267 girls. All testing was carried out in the child's own school. The spirograms were recorded with a dry spirometer from which the FVC, FEV1, and FMF were measured. Correlation coefficients were established between each of these ventilatory parameters and anthropometric measurements of height, mass, arm span and age. The findings of the study revealed high correlations for both boys and girls between ventilatory parameters of FVC and FEV1 and height, mass, arm span and age. Moderately high correlations were found for both sexes between FMF and height, mass, arm span and age. Height correlated best with each of these ventilatory measures. It was also established that significant improvement in some correlations was obtained when anthropometric values were used in multiple correlation analysis. The use of height plus mass proved to be best when predicting FVC and FEV, for boys and girls, and for predicting FMF of girls. FMF for boys could be best predicted by using height alone. The limits of normality for ventilatory parameters of FVC, FEV1 and FMF were found to be best defined by the per cent standard error of the estimate. Tables and nomograms were established from regression and multiple regression equations in order to predict normal values in children. The findings of this study revealed that little difference existed between the ventilatory values of children tested in Perth, Europe and the Eastern States of Australia. However, the differences that were found to exist could be due to the age group which was sampled or possible environmental and genetic differences.