Correlation of peak expiratory flow rate and single breath count in normal adults

Sushama A. Bhandare, Sayali S. Rasal, Saraswati K. Iyer


Background: Spirometry mandates the requirement of equipments and skilled technicians which may be difficult to acquire in resource limited situations. Thus simple alternative tests like Peak Expiratory Flow Rate (PEFR) and Single Breath Count (SBC) can be used to assess the pulmonary functioning of an individual.

Methods: Hundred healthy participants of both genders between the age group of 18-50 years were recruited for this study. They were asked to perform PEFR using the Mini Wright Peak Flow Meter and SBC using a metronome. Three reading were noted and the best of three readings were used for analysis.

Results: The mean age and BMI of the participants were 31.54±10.42 years and 23.88±5.14 kg/m2 respectively. The Spearman’s correlation coefficient of PEFR and SBC was 0.7048 with p<0.001 indicating a strong positive correlation.

Conclusions: SBC can be used as a simple, convenient and cost-effective alternative to PEFR to assess pulmonary function in adults.  


Peak expiratory flow rate, Single breath count, Spirometry

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