pobj: An object of class pmods (pooled models), produced by a previous call to psfmi_lr.
folds: The number of folds, default is 3.
p.crit: A numerical scalar. P-value selection criterium used for backward during cross-validation. When set at 1, pooling and internal validation is done without backward selection.
BW: If TRUE backward selection is conducted within cross-validation. Default is FALSE.
cv_naive_appt: Default is TRUE for showing the cross-validation apparent (train) and test results. Set to FALSE to only give test results.