OBJECTIVES: The diagnosis of upper GI disorders is based on symptoms or endoscopic findings. This study evaluated whether the severity and frequency of upper GI symptoms correlate with endoscopic findings. METHODS: This was a single visit cross-sectional study, regarding primary care patients with upper GI symptoms and recent endoscopy data. Investigators (gastroenterologists) recorded demographic data, medical history and endoscopic findings. Frequency and severity of GERD (heartburn/regurgitation) and dyspeptic symptoms (epigastric pain/early satiety/postprandial fullness) were recorded by a patient questionnaire. RESULTS: A total of 112 investigators recruited 1120 patients (male/female: 604/516, mean age:50 years, mean BMI:27 kg/m2) in two periods (November-December 2006 and June-September 2007). Upper GI symptoms for ≥2 days in the last week were reported by 98% of patients (GERD:71%, Dyspepsia:76%). Symptoms were present for 3-5 and 6-7 days/week in 51% and 30% of patients, respectively, and were mild, moderate or severe in 14%, 57% and 28% of patients, respectively. The predominant endoscopic findings were peptic ulcer (26%), esophagitis (43%), gastritis (14%) and hiatus hernia (5%). In these groups, upper GI symptoms were present for ≥3 days/week in 83%, 83%, 79% and 71% of patients, respectively, and were moderate/severe in 88%, 88%, 81% and 84%, respectively. Among patients with esophagitis, GERD symptoms were present for ≥3 days/week in 47%, 56%, 63% and 86% and were moderate-to-severe in 68%, 95%, 100% and 100% of cases with LA grade A, B, C and D, respectively. CONCLUSIONS: The majority of patients with upper GI symptoms visiting gastroenterologists have frequent (98%) and moderate-to-severe (86%) symptoms. The severity and frequency of symptoms may be affected by the severity of endoscopic findings. However, they cannot be used as predictors of endoscopic findings, because frequent and moderate-to-severe symptoms are reported not only by most patients with more severe but also most of those with milder endoscopic findings.