Fig. 2From: Comparison of methacholine and mannitol challenges: importance of method of methacholine inhalationMannitol DRS (mg/% FEV1 fall) on the vertical axis) and methacholine PD20 (μg) on the horizontal axis. The dotted red lines indicate the cut points below which the values indicate AHR to mannitol (42.3 mg/% FEV1 fall) or methacholine (400 μg) respectively. All values log transformed for analysisBack to article page