Normal measurement of peak expiratory Flow rate in the high school children in Babol, north of Iran

Peak Expiratory Flow Rate (PEFR) is recommended as a tool for control of asthma. The purpose of this study was to determine the normal value of PEFR in the healthy high school children in Babol, Iran. This study was conducted on 470 healthy high school children (285 girls, 185 boys with the age between 14-18 years). For the determination of PEFR we used Mini Wright Peak Flow Meter. At a three time measurement, the highest value of PEFR is recorded. Formula for prediction of PEFR was estimated by linear regression analysis after the correlation of PEFR with the age, height and weight. The mean PEFR in the boys was 546.57±74.92 and in the girls was 424.48±52.29L/m. The amount of PEFR was increased regarding age, height and weight. The formula for prediction of PEFR was estimated: For boys: weight ×1.59+height×2.24+age×1.47-135,For girls: weight ×0.86+height×1.46+143.17 The results show that the normal range of PEF is different from that reported to the other countries.