Applicability of established regression equations in the prediction of peak expiratory flow rate in Indian adults

BACKGROUND: Peak expiratory flow rate (PEFR) helps in the assessment of airflow limitation. Its relationship with age and height has been established in several previous studies with different sample size in different regions from India. A large-scale study (in 2014) established a set of regression equations with a national level reference regression equation. AIM: The aim of this study was to check the applicability of established regression equations in the prediction of PEFR in apparently healthy young adults. MATERIALS AND METHODS: A cross-sectional study was conducted with 104 young adults (males = 55, females = 49). PEFR (L/min) was measured using computerized spirometer. Established regression equations from the previous study were used to predict PEFR from the age and height of the participants. Measured PEFR values were compared with predicted values by the paired t-test with α = 0.05. Further, the prediction was considered “comparable” if the value was <±10% of the measured value. RESULTS: Measured versus predicted mean PEFR (from regression equation established for adult Indian national) for male was 481.99 ± 63.52 L/min versus 496.04 ± 20.70 L/min (P = 0.096) and female was 365.19 ± 61.36 L/min versus 336.82 ± 13.78 L/min (P < 0.001). In male, 54.55% and in female, 44.90% was comparable prediction from regression equation established for Indian adult national. CONCLUSION: Estimated PEFR in male showed fair comparable prediction and female showed poor comparable prediction. Further studies, including all Indian states with a large sample, may help in the establishment of more accurate prediction equations.