A hiatal hernia occurs when a portion of the stomach prolapses through the diaphragmatic esophageal hiatus. Even though it is believed that the major cause of hiatal hernias is loss of elasticity of supporting structures, the detailed mechanisms have not been fully studied. There are reports of a possible association between hiatal hernias and connective tissue weakness. Recently, studies of inguinal and incisional hernias have shown their connection to collagen matrix defects. The study reported here uses data mining techniques to explore the association between paraesophageal hernia and severe types of hiatal hernia and other disorders, including collagen.