pred_GLI: Calculate predicted values of spirometry parameters using GLI-2012 equations
Description
This function calculates the mean normal (predicted) values for the various spirometry
parameters, using the GLI-2012 equations. It accepts as input age, height, gender and ethnicity.
If param has length one, the function returns a numeric vector. If param
has length >1, it returns a data.frame with length(param) columns.
Arguments
age
Age in years
height
Height in meters
gender
Gender (1 = male, 2 = female) or a factor with two levels (first = male). Default is 1.
ethnicity
Ethnicity (1 = Caucasian, 2 = African-American, 3 = NE Asian, 4 = SE Asian,
5 = Other/mixed). Default is 1.
param
A character vector, containing one of more of the following parameters (case insensitive):
"FEV1", "FVC", "FEV1FVC", "FEF2575", "FEF75", "FEV075", "FEV075FVC"
Details
Arguments age, height, gender and ethnicity are vectors
of equal length, or of length one, in which case the value is recycled; if the four vectors are
not of equal length, the function stops with an error.