Although there remains no gold standard for the diagnosis of GERD, ambulatory esophageal pH monitoring can provide data to guide further evaluation and treatment of patients with GERD-associated symptoms. In the past, an indwelling nasoesophageal catheter was the only way to measure esophageal acid exposure. Because this method is associated with nasal and pharyngeal discomfort and rhinorrhea, patients may have limited their activity and become more sedentary during the monitored period.[5] This may have resulted in less acid reflux and a false negative test.