Appendicitis and gastroesophageal reflux disease (GERD) are both prevalent diseases and might share similar pathological mechanisms. The aim of this study was to investigate the association between GERD and appendicitis using a large population-based dataset. This study used administrative claims data from the Taiwan Longitudinal Health Insurance Database 2005. We identified 7113 patients with appendicitis as cases, and 28452 matched patients without appendicitis as controls. This study revealed that GERD was found in 359 (5.05%) cases and 728 (2.56%) controls (p
