Variable	βj	Imputed valuesa
General appearance	0.719	1.144
Wheezing	0.936	0.558
Rales/rhonchi	1.150	0.507
Retractions	1.360	0.691
Cyanosis	0.812	0.050
Lethargy	0.475	0.190
Poor air movement	0.735	0.134
Worst room air SaO2	-0.078	90.360
Maximum respiratory rate	0.034	57.015

^aimputed values were defined as the mean value calculated from all subjects