Fig. 5
Funnel plots for studies included in the (a) FEV1, (b) morning PEF and (c) FEF25–75% endpoints meta-analyses. a. Linear regression test of funnel plot asymmetry: t = −0.2342, df = 7, p-value = 0.822. b. Linear regression test of funnel plot asymmetry: t = 1.332, df = 7, p-value = 0.225. c. Linear regression test of funnel plot asymmetry t = 1.547, df = 6, p-value = 0.262. FEF25–75%, % predicted forced expiratory flow between 25% and 75% of forced vital capacity; FEV1, forced expiratory volume in 1 s; PEF, peak expiratory flow