Spirometry is a basic diagnostic tool in pulmonary medicine, also used in children. Recently new sets of reference values have been published (Stanojevic et al; AJRCCM 2009, (1)) and the so called GLI2012 (Quanjer et al. ERJ 2012 (2)) that allow interpretation of spirometry in children as young as 3 years of age.
The aim of a present study was to verify what is the distribution of calculated reference values (% predicted and z-score) in a group of children without signs of obstruction. The analysis was performed on the results obtained in 152 children aged 4-10 yrs, who before spirometry underwent oscillometric measurements (IOS) and had normal respiratory resistances, to exclude those with potential obstruction. We have analysed FEV1/FVC with both reference equations sets and also FEV0.75/FVC using equation of Stanojevic et al.
The table presents the results:
|z-score (mean SD)||range||pr. predicted.|
|FEV1/FVC GLI2012||0,098 0,80 (NS)||-1,54 2,14||100,2 5,1|
|FEV1/FVC Stanojevic||-0,15 0,79 (NS)||-1,81 1,88||98,7 5,1|
|FEV0.75/FVC Stanojevic||-0,21 0,77 (NS)||-1,75 1,92||97,9 6,3|
NS - not different from 0 by Student's t-test
The results show, that in a group of children , potentially non-obstructed, z-scores have normal distribution with mean value close to zero and SD approaching 1. The equations for reference values can be used in Polish children
1. S. Stanojevic et al. Spirometry centile charts for young Caucasian children. AJRCCM 2009; 180:547-552.
2. Quanjer P.H.,.et al. Multi-ethnic reference values for spirometry for the 3-95-yr age range: the global lung function 2012 equations. ERJ 2012,40: 1324-1343.