Table 4. The incidence of mucoid impaction and other HRCT abnormalities among different asthma severities.

Parameters	Mild asthma, n (%)	Moderate asthma, n (%)	Severe asthma, n (%)	Total, n (%)
Mucoid impaction*	2 (6.70)	5 (15.20)	23 (38.30)	30 (24.40)
Emphysema*	1 (3.30)	0 (0.00)	26 (43.30)	27 (22.00)
Mosaic lung attenuation†	1 (3.30)	0 (0.00)	6 (10.00)	7 (5.70)
Atelectasis	0 (0.00)	0 (0.00)	2 (3.30)	2 (1.60)

*, significant differences were found in prevalence of mucoid impaction and emphysema among different asthma severity groups (P<0.05). ^†, no significant difference was found in incidence of mosaic lung attenuation among different asthma severity groups (P>0.05). HRCT, high-resolution computed tomography.