Objective: The primary aim of our study was to assess the variation of PEFR with various anthropometric measurements in medical students of Karachi, Pakistan.

Design: Cross-sectional study.

Setting: Medical students of Karachi Medical and Dental College.

Participants: 276 non-smoker healthy medical students composed of 168 females and 108 males.

Variable parameters: They include mean age, body height and body weight and PEFR. They were marked separately for each gender.

Results: The mean waist hip ratio in females was observed to be 0.843±0.111 in relation with that of mean PEFR value 452.97±65.84 L/min, whereas in males the mean waist hip ratio was 0.864±0.028 in relation with that of mean PEFR value 445.93±66.49 L/min. Also there is a statistically significant variation in PEFR with an increase in waist hip ratio. The mean height of males was 173.63±7.5 cm and weight was 61.81±11.25 Kg while mean height of females was 158.56±7.3 cm and weight was 49.33±9.04 Kg. PEFR is positively correlated with increase in height and weight up to a certain limit.

Conclusion: The study concludes that PEFR is affected positively by variation in waist hip ratio; moreover young females have more