Figure 3
From: Identification of acid reflux cough using serial assays of exhaled breath condensate pH
Multi-sample EBC pH profiles of controls and patients. Chronic cough patients are separated into three groups: those who subsequently showed minimal or no response to proton pump inhibition (PPI Non-responders); those who had substantial clinical response to proton pump inhibition (PPI responders), and those who elected to not take the prescribed proton pump inhibitor but who nonetheless had substantial improvement in cough (Spontaneous Resolver). EBC pH profiles are noted as positive if a cough was associated with a low EBC pH value on 1 or more occasions and one or more other EBC pH values was normal. Note the high predictive values of positive and negative EBC pH profiles for response to proton pump inhibition.