Fig. 1

Mean non-asthmatic (control), baseline and post-treatment methacholine dose-response curves at 1 h (a), 24 h (b), and 48 h (c) are shown. The methacholine concentration causing a minimum 20% fall in FEV1 at baseline is designated as zero on the x-axis (i.e. corresponds to the final data point on baseline curves). Mean responses below (three) and above (five) comprise the post-treatment dose-response curves. Only data points with at least n = 8 are included. The sample size for each curve is: n = 15 for LAMA, n = 16 for uLABA, and n = 14 for combo