Figure 3From: Diagnosing asthma in general practice with portable exhaled nitric oxide measurement – results of a prospective diagnostic study Box-Plot of FENO measures in relation to the diagnoses of the reference standard (body plethysmography and bronchial provocation). (Black circle) mild outlier between 1.5th and 3rd interquartile range. (Black asterisk) extreme outlier more than 3rd interquartile range.Back to article page