Optimal prediction of spirometric indices
From
birth to adolescence leg length grows faster than trunk
height. This process comes to an end at about the age
of sexual maturity. It will therefore not come as a
surprise that lung volume, a component of the contents
of the trunk, cannot be predicted solely on the basis
of standing height; somehow age should enter into the
equation.
The prediction of lung volumes is appreciably improved
by taking interaction between age and standing height
into account. This eliminates any residual trend between
residual and age. In boys a weak age-related trend remains,
but it is small and quite acceptable for practical purposes.
The prediction equation is of the form:
loge(FVC) or loge(FEV1) = a + (b + c·age)·height.
It was developed from analysis of data from 2269 girls and 3592 boys from England, Italy, the Netherlands, Austria and Spain (ref. 1). The equation fits each of the geographical subsets of children and adolescents and is valid for girls between ages 6-16 yr, and boys between 6-18 yr. The resulting equations are given in the next page.
See also:
Reference values for adults
SpirXpert software
| Ref. 1 - Reference values for children and adolescents | |
| Quanjer PhH, Borsboom GJJM, Brunekreef B, Zach M, Forche G, Cotes JE, Sanchis J, Paoletti P. Spirometric reference values for white European children and adolescents: Polgar revisited. Pediat Pulmonol 1995; 19: 135-142. | |