Normal reference value of forced vital capacity of Chinese younger women and geographical factors / 西安交通大学学报·英文版

ABSTRACT

Objective: To supply a scientific basis for standardizing the normal reference value of forced vital capacity (FVC) of Chinese younger women. Methods: We studied the relationship between the normal reference value of 21 767 samples of FVC of younger women and eight geographical factors in 157 areas in China. Results: It was found that the correlation between geographical factors and the normal reference value of FVC of younger women was quite significant (F = 5.884, P = 0.000). By adopting the method of mathematical regression analysis, one regression equation was inferred: Y = 3.146+0.00006919X1+0.01315X4-0.006966X6+0. 09524X8±0.254. In the above equation, Y is the normal reference value of younger women' FVC (L); X1 is the altitude (m); X4 is the annual mean air temperature (°C); X6 is the annual mean relative humidity (%); X8 is the annual mean wind speed (m/s); 0.254 is the value of the residual standard deviation. Conclusion: If geographical values are obtained in a certain area, the normal reference value of FVC of younger women in this area can be obtained by using the regression equation. Furthermore, according to the geographical factors, China can be divided into eight regions: Northeast China Region, North China Region, Shanxi-Shaanxi-Inner Mongolia Region, middle and lower reaches of the Yangzte River Region, Southeast China Region, Northwest China Region, Southwest China Region, and Qinghai-Tibet Plateau Region.