Distribution of Positive Responses for each Berlin Questionnaire Symptom Category by Group. Distribution of positive responses for each Berlin Questionnaire symptom category by group. Category 1 was positive if the subject had persistent snoring symptoms. Category 2 was positive if the subject had persistent daytime somnolence and/or drowsiness while driving. Category 3 was positive if the subject had a body mass index ≥ 30 kg/m2 or history of hypertension. BE, Barrett’s esophagus. EGD, esophagogastroduodenoscopy control group. COL, colonoscopy control group. Cat., category. * P ≤ 0.01 vs. EGD group.