TABLE 2

Fitting comparison by regression model type

EstimateStandard errorT-valuep-valueAdjusted R2AICBIC
Linear model
 Intercept−3039.01206.02−14.75<0.0010.5569 581.4069 619.84
 Sex634.3225.7524.63<0.001
 Age−16.500.79−20.66<0.001
 Height29.221.4619.95<0.001
 Weight16.171.1114.48<0.001
Polynomial model
 Intercept−1469.00158.80−9.25<0.0010.5669 480.1569 531.40
 Sex673.0025.8925.99<0.001
 Age16.874.813.50<0.001
 Age2−0.470.06−7.31<0.001
 Height20.07<0.0116.52<0.001
 Weight39.705.177.67<0.001
 Weight2−0.160.03−5.05<0.001
Additive model
 Intercept−2537.29224.98−11.28<0.0010.5769 342.8169 449.50
 Sex743.3526.3028.26<0.001
 Height24.301.5215.91<0.001
 Weight12.571.1211.21<0.001
 S(age): male4.263#5.26022.59+<0.001
 S(age): female7.391#8.28870.38+<0.001

AIC: Akaike Information Criterion; BIC: Bayesian Information Criterion; S(age): spline function for age per sex. Sex: 0=female, 1=male; age=years; height=centimetres; weight=kilograms. #: effective degrees of freedom; : reference number of degrees of freedom; +: F-value.