Patients complete a family history questionnaire. Epidemiological data is also collected about environmental exposures, such as smoking and alcohol history. Any siblings or other living family members affected by heartburn identified from this survey are then contacted to validate their symptoms/diagnoses and to collect other relevant epidemiological data. Family members with heartburn are offered a screening endoscopy for the presence of Barrett's esophagus. In the absence of an endoscopy, a symptom nomogram predictive for the presence of Barrett's esophagus is used.