Diagnostic properties of a symptoms scale for diagnosing reflux esophagitis.

ABSTRACT

OBJECTIVE: To the objective of the study was to determine accuracy and predictive values of a symptoms scale for diagnosing reflux esophagitis (RE). STUDY DESIGN AND SETTING: Standard criterion study. All recruited patients from two centers in Chile underwent both digestive endoscopy (reference standard) and a symptoms scale known to be valid and reliable for diagnosing gastroesophageal reflux disease. The RE variable was dealt with dichotomously. A receiver operating characteristic curve was constructed. Sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios of the scale were calculated. RESULTS: Two hundred and thirty eight (238) subjects (57.6% female), with an average age of 44.2+/-13.0 years were included. Of these, 57.1% presented with RE. With a cut-off score of six, association was confirmed between the symptoms scale and RE with an odds ratio of 7.26 and a correct classification i.e. diagnostic accuracy of 73.1%. Sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios, of 74.3%, 71.6%, 77.7%, 67.6%, 2.61, and 0.36 respectively, were obtained. CONCLUSION: A seven-item symptoms scale when compared to endoscopy as gold standard was useful for diagnosing RE. Using a cutoff of six points, the diagnostic accuracy of the scale was 73.1%.