Age , gender , IgE levels , eosinophil numbers , and spirometric measurement parameters including forced expiratory volume in 1 sec ( FEV1 ) , forced expiratory flow 25 % -75 % ( FEF25 % -75 % ) , forced vital capacity ( FVC ) , peak expiratory flow percentage ( PEF % ) , and peak expiratory flow rate ( PEFR ) were compared using the Mann-Whitney U test and the Wilcoxon test .