Ong et al evaluated pulmonary function tests in malnourished children from West Bengal, India. They identified equations that can be used to estimate target values based on sitting height and weight. The authors are from the University of Dundee.
Patient selection: malnourished children from 3 to 17 years (page 18)
Parameters:
(1) sitting height in cm
(2) body weight in kilograms
Predicted pulmonary function tests:
(1) FEV1 (forced expiratory volume in 1 second) in liters
(2) FVC (forced vital capacity) in liters
(3) PEFR (peak expiratory flow rate) in liters per second
observed pulmonary function test as percent of predicted =
= (observed value) / (predicted) * 100%
For Boys
predicted FEV1 in liters =
= EXP(X)
X =
= (1.080 * (LN(sitting height))) + (0.657 * (LN(weight))) - 6.261
predicted FVC in liters =
= EXP(Y)
Y =
= (LN(sitting height)) + (0.669 * (LN(weight))) - 5.918
predicted PEFR in liters per second =
= EXP(Z)
Z =
= (0.781 * (LN(sitting height))) + (0.614 * (LN(weight))) + 0.378
For Girls
predicted FEV1 in liters =
= EXP(X)
X =
= (1.268 * (LN(sitting height))) + (0.518 * (LN(weight))) - 6.667
predicted FVC in liters =
= EXP(Y)
Y =
= (1.233 * (LN(sitting height))) + (0.527 * (LN(weight))) - 6.529
predicted PEFR in liters per second =
= EXP(Z)
Z =
= (1.545 * (LN(sitting height))) + (0.338 * (LN(weight))) - 2.093
NOTE: While working on the spreadsheet it became apparent that the predicted PEFR by these equations are significantly higher than expected and what seems reasonable. Using -7.093 for girls gives a more reasonable value, suggesting a typographical error. Alternatively the PEFR value does not need to be made EXP.
