Table 2. Background and DLR values of conservative management and surgical management groups.

Patients data	Conservative management (Group A + Group C)	Surgical management (Group B)	P value
N (M:F)	14 (8:6)	28 (15:13)
Age (months)	9.9±10.4	7.4±4.7	0.749
Body weight (kg)	6.4±2.6	5.9±1.8	0.604
Tracheal diameter (mm)	4.5±0.7	2.8±0.5	<0.05
Tracheal length ratio (%)	50 [21–68]	56 [33–80]	0.254
Cardiac abnormality	7/14 (50%)	13/28 (47%)	0.827
Mortality rate	0/14 (0%)	3/28 (12%)	0.204
History of intubation	2/14 (14%)	14/28 (50%)	<0.05
DLR (diameter/length ratio)	10.1±5.2	5.3±2.0	<0.05