Background: Pulmonary function tests are done to access the changes in the respiratory system and its functions. PEFR is the maximal flow which is achieved during the expiration, which is delivered with maximal force. PEFR is considered as the simplest index of pulmonary function. Such study has not been conducted earlier in this region. Similar other prior studies gave varied results regarding influence of BMI and height, weight on PEFR readings.

Objective: to study the variation of PEFR with respect to the anthropometric parameters among males and females subjects of age group of 18-35 years.

Materials and Methods: this was a cross sectional study, conducted at Silchar Medical College, Department of Physiology, Assam, India. The ethical committee clearance was taken from Institutional Ethical Committee. The subjects with no cardio respiratory disease, non smokers or medicine users that can influence cardio respiratory function were added in the study. PEFR was measured with the subject seated comfortably during the same time of the day for all subjects. Instrument used was Schiller’s Spirovit SP -1 spirometer. Height was recorded using stadiometer and weight was recorded using weighing machine

Results: Out of total subjects, 52% were males, 48% were females. PEFR was highly significant in males. For height 145-155 cm, PEFR is highly significant in males, for height 160-165 cm, PEFR is significantly high in males. Also PEFR is significantly higher in overweight males.

Conclusion: PEFR is higher in males than females subjects, in all age groups. The effect of height, age, weight, BMI on PEFR have all been discussed.