Background: Gastroesophageal reflux symptoms are frequent in the general population, but there is a lack of information about its prevalence and valid and reliable scales to determine it. Aim: To design a valid and reliable scale to determine gastroesophageal reflux disease. Subjects and methods: A Cross-sectional study with patients and controls was conducted. The diagnosis of gastroesophageal reflux was based of clinical plus radiological, endoscopic or pathologic criteria. A structured questionnaire was built, containing items covering different clinical manifestations of gastroesophageal reflux disease. All subjects were subjected to 24 h esophageal pH monitoring. Internal consistency of items, interobserver reliability, criterion and construct validity, sensitivity, specificity and predicted values were obtained. Results: One hundred thirteen subjects (74 female and 39 male with a mean age of 46 years old) were studied. Seventy three had gastroesophageal reflux and 40 were controls. Internal consistency of the score was 0.82. Inter observer reliability was greater than 0.80 and a significant association was observed between the score and 24 h esophageal pH monitoring (p <0.001). Instrument sensitivity was 97% and specificity 83%. Conclusions: The designed scale proved to be a valid and reliable instrument to measure gastroesophageal reflux symptoms, that can be used for future prevalence studies.