Extending an ambulatory pH study by using a wireless capsule system could improve diagnosis of gastroesophageal reflux disease in patients with symptoms potentially related to acid reflux events. We determined the relative value of a 2-day versus a 1-day study in detection of abnormal esophageal acid exposure and reflux symptom associations.
Division of Gastroenterology, Washington University School of Medicine, 660 S. Euclid Avenue, Campus Box 8124, St. Louis, MO 63110, USA. cprakash@im.wustl.edu