OBJECTIVES: The aim of this study was to gather epidemiological data in a GERD population and to evaluate the added value of the GERD Impact Scale (GIS) as a useful tool for patient management of GERD. The GIS (score range 1–4)  is a patient questionnaire designed to aid physicians to identify the appropriate treatment and to evaluate the patient’s response to treatment. METHODS: Patients from 296 centers with GERD and esophagitis grade A to D (LA classification) were included. The physician decided at inclusion whether to initiate or change the GERD treatment. Patients’ symptoms treatment changes and GIS were assessed during the study. RESULTS: 2001 patients (55 years, 52% female, BMI 26kg/m2) were included. Median interval between first GERD onset and study entry was 1.2 years. Twenty-five percent never received any treatment, 25% received antacids, 25% H2-receptorblockers, 15% had received empiric PPI therapy and 30% PPI following endoscopy. In 99% of cases, physicians prescribed PPIs (esomeprazole [82%]) with a daily dose of 40mg. The dose was changed to 20mg at visit 2 in 60% of patients. The severity of GERD symptoms decreased throughout the study with 89% of patients having moderate or severe GERD in visit1, 31% in visit2 and 14% in visit3. Concurrently, the GIS scores decreased significantly (-1.18 for upper GI symptoms, -1.07 for other related GI symptoms and -0.96 for the impact on life). GIS scores correlated significantly but  moderately with the physician’s clinical judgment and weakly with endoscopy findings. GIS was judged useful for 80% of patients.  CONCLUSIONS: GIS scores improved with GERD PPI treatment and were judged helpful by the physician. GIS may thus have an added value over these assessments in determining the appropriate treatment and evaluating the patient’s response to this treatment.