PH monitoring is not capable of detecting all types of reflux, especially when the amount of acid is very low or not at all in the refluxate. Multichannel intraluminal impedance-pH monitoring (MII-pH) is used as a new method to assess bolus transport. The types of reflexes including acid, weak acid and weak alkaline MII-pH is capable of distinguishing more reflux episodes based upon use of physical and chemical parameters of the refluxate, leads to a diagnosis of normal acid reflux from abnormal nonacidic reflux. 24-h oesophagal pH monitoring can be effectively used to assess the potential relationship between symptoms and refluxes. MII-pH is capable of distinguishing more reflux episodes based upon use of physical and chemical parameters of the refluxate, leads to a diagnosis of normal acid reflux from abnormal nonacidic reflux. It can be used to confirm gastro-oesophagal reflux episodes, where has a sensitivity and specificity for diagnosing GERD in comparison with endoscopy or pH-metry.