title: Initial validation of a questionnaire for detecting gastroesophageal reflux disease in epidemiological settings.
abstract: There is a high prevalence of gastroesophageal reflux disease (GERD) in the general population. Prevalence studies are scarce, and there is a lack of valid instruments for measuring them. The aim of this paper is to validate a questionnaire for detecting GERD. A validity study design with pathologic GERD patients and controls was used. A sample of 240 subjects age and sex paired was selected in the ratio of 3:1 (patients to controls). The initial structured questionnaire contained a variety of GERD symptoms. Internal consistency, interobserver reliability, criteria validity using 24-h esophageal pH monitoring, construct validity, and extreme group validation were assessed. Sensitivity, specificity, and predictive values were also obtained in different cutoff points of the definitive scale. A total of 180 confirmed GERD patients and 60 controls were included in the study. Mean age in years was 45 +/- 13, with no statistical difference by gender (67% were female). Internal consistency of 0.75 and interobserver reliability of 0.87 was achieved in building the scale. Extreme group validation was highly significant by assessing the scale score with 24-h esophageal pH monitoring (P <.0001). At cutoff point 3 of the scale and with a correct classification of subjects of 92.4%, sensitivity, specificity, positive, and negative predictive values were 92, 95, 98, and 79%, respectively. The conclusion of this article is that a reliable and valid instrument was built to detect GERD.
authors.affiliation: Department of Surgery, Universidad de La Frontera, Casilla 54-D, Temuco, Chile. cmantero@ufro.cl
authors.forename: Carlos
authors.initials: C
authors.lastname: Manterola
authors.forename: Sergio
authors.initials: S
authors.lastname: Muñoz
authors.forename: Luis
authors.initials: L
authors.lastname: Grande
authors.forename: Luis
authors.initials: L
authors.lastname: Bustos
mesh_terms: D000328:Adult; D015340:Epidemiologic Research Design; D005260:Female; D005764:Gastroesophageal Reflux / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D011795:Surveys and Questionnaires