TABLE 1.

Study population and image processing steps with number and percent of total participants at each stage. All imaging is post-bronchodilator. Percentages in the Healthy and Asthmatics columns are relative to the starting population; percentages in the Severe column are relative to the corresponding population at that stage.

Image acquisition and processing stages	Healthy N (%)	Total asthmatics (severe + moderate) N (%)	Severe N (%)
1. Total SARPIII asthmatic population at UW-Madison	5 (100%)	100 (100%)	62 (62.0%)
2. Subjects with HP 3He MRI	5 (100%)	78 (78%)	48 (61.5%)
3. With inspiratory and expiratory CT	4 (80%)	34 (34%)	21 (61.7%)
4. With scored segmental mucus plugs	4 (80%)	34 (30%)	21 (61.7%)