Study Population
Asthmatic children aged three to 10 years, who presented to our clinic
were enrolled consecutively. Asthma was diagnosed according to GINA
guidelines with recurrent bronchial obstruction findings and clinical or
lung function test reversibility with inhaled bronchodilator
treatment8.
Inclusion Criteria were 1) age three to 10 years 2) diagnosed or
followed up with asthma 3) no bronchodilator use during the last one
week. Exclusion criteria were 1) asthma exacerbation during the last one
week 2) diagnosis of CF, immunodeficiency or bronchiectasis that may
change lung function tests 3) premature birth.
Sample size was calculated based on the R values of the IOS
measurements; We expected to have a 1:3 ratio of overweight: normal
weight ratio in the group, when we predicted a standard deviation (SD)
of 0.2 and minimal effect size of 0.1, the sample size required was 168
to get a power of 80%.