Regression Equations for Peak Expiratory Flow Rates for Children (8–12 years) in Ernakulam District

Abstract

Objective: The objective of this study was to study the peak expiratory flow rate (PEFR) in healthy school going children between 8 and 12 years in Ernakulum district and derive a regression equation to predict expected PEFR. Methods: A cross-sectional study was done in schools of Ernakulum among healthy children between 8 and 12 years of age. Pro formas and consent forms were distributed to schools who gave their consent for participating in this study. Eligible children were examined, anthropometric measures were taken, and PEFR values were recorded using a Mini-Wright peak flow meter. The best of the three recordings was taken to compare against each variable. Statistical analysis was carried out using statistical package, SPSS (version 22.0.0.0). Results: A total of 954 students between 8 and 12 years were studied, of which 482 were boys and 472 were girls. The scatter diagram for PEFR and age, height, weight, body mass index, and chest circumference for boys and girls suggests that there is a significant positive correlation between PEFR and the studied variables. Based on the multiple regression analysis, only age and height have a significant effect on PEFR for both males and females. The regression equation based on both height and age is PEFR = −150.290 + 1.811 (height) + 10.831 (age) for males and PEFR = −149.623 + 1.813 (height) + 8.329 (age) for females. Conclusion: Among different factors affecting PEFR, height and age correlate better with PEFR than the other variables studied. The derived regression equations can be used to predict the regional reference value.

Keywords

• Asthma
• peak expiratory flow rate
• regression equations