Table 1. Clinical characteristics of patients.

Variablea	Frequency (n=30, %)
Age, years	16.04±5.09
Sex, male	28 (93.0)
Haller index	3.37±0.88
Asymmetrical, n	3 (10.0)
Comorbidity
Bronchiectasia	1 (3.3)
Spinal curvature	1 (3.3)
Mitral valve prolapse	1 (3.3)
ASA physical status
I	27 (90.0)
II	3 (10.0)
III	0

^a, continuous data are shown as mean ± standard deviation, and categorical data as number (%). ASA, American Society of Anesthesiologists.