Development and validation of a simple and multifaceted instrument, GERD-TEST, for the clinical evaluation of gastroesophageal reflux and dyspeptic symptoms

AIM To evaluate the psychometric properties of a newly developed questionnaire, known as the gastroesophageal reflux and dyspepsia therapeutic efficacy and satisfaction test (GERD-TEST), in patients with GERD. METHODS Japanese patients with predominant GERD symptoms recruited according to the Montreal definition were treated for 4 wk using a standard dose of proton pump inhibitor (PPI). The GERD-TEST and the Medical Outcome Study Short Form-8 Health Survey (SF-8) were administered at baseline and after 4 wk of treatment. The GERD-TEST contains three domains: the severity of GERD and functional dyspepsia (FD) symptoms (5 items), the level of dissatisfaction with daily life (DS) (4 items), and the therapeutic efficacy as assessed by the patients and medication compliance (4 items). RESULTS A total of 290 patients were eligible at baseline; 198 of these patients completed 4 wk of PPI therapy. The internal consistency reliability as evaluated using the Cronbach's α values for the GERD, FD and DS subscales ranged from 0.75 to 0.82. The scores for the GERD, FD and DS items/subscales were significantly correlated with the physical and mental component summary scores of the SF-8. After 4 wk of PPI treatment, the scores for the GERD items/subscales were greatly reduced, ranging in value from 1.51 to 1.87 and with a large effect size (P < 0.0001, Cohen's d; 1.29-1.63). Statistically significant differences in the changes in the scores for the GERD items/subscales were observed between treatment responders and non-responders (P < 0.0001). CONCLUSION The GERD-TEST has a good reliability, a good convergent and concurrent validity, and is responsive to the effects of treatment. The GERD-TEST is a simple, easy to understand, and multifaceted PRO instrument applicable to both clinical trials and the primary care of GERD patients.