Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 3 1 2004 03 15 21 24 Mohammad Gharagozlou Farshid Kompani Masoud Movahedi 2015 10 01 This study was conducted to evaluate whether forced expiratory volume in 1 second (FEV1) for the diagnosis of bronchial reactivity by means of the free-running exercise test and bronchodilator inhalation, could be appropriately replaced by simple measurements of peak expiratory flow rate (PEFR) in children. We studied 108 referred symptomatic children (due to chronic cough or wheezing) suspected to have asthma aged 5-14y.  Forced  breathing  spirometry and  the  "Mini-Wright  peak  flow  meter" tests were  recorded  before  and  fifteen  minutes after  the  challenge  with free- running exercise or bronchodilator (Salbutamol) inhalation,  regarding the baseline FEV1 value (FEV1> 80%  considered as normal). There was a high correlation between PEFR and FEV1 (in absolute value   and   percent   predicted) measured before and after bronchodilator inhalation test (r = 0.48, P = 0.05) in comparison to the values referred to free- running exercise test (r = 0.26, P = 0.01). "forced breathing spirometry" and "Mini-Wright peak flow" cannot be used interchangeably for diagnosing asthma, and PEFR measurement should remain a procedure  for monitoring and following up the patients. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/63 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/63/63