Reliability and validity of the Gastrointestinal Symptom Rating Scale (GSRS) and Quality of Life in Reflux and Dyspepsia (QOLRAD) questionnaire in dyspepsia: A six-country study
Background: Symptoms of dyspepsia significantly disrupt patients' lives and reliable methods of assessing symptom status are important for patient management. The aim of the current study was to document the psychometric characteristics of the Gastrointestinal Symptom Rating Scale (GSRS) and the Quality of Life in Reflux and Dyspepsia questionnaire (QOLRAD) in Afrikaans, German, Hungarian, Italian, Polish and Spanish patients with dyspepsia. Methods: 853 patients with symptoms of dyspepsia completed the GSRS, the QOLRAD, the 36-item Short-Form Health Survey (SF-36) and the Hospital Anxiety and Depression scale. Results: The internal consistency reliability of the GSRS was 0.43-0.87 and of the QOLRAD 0.79-0.95. Test-retest reliability of the GSRS was 0.36-0.75 and of the QOLRAD 0.41-0.82. GSRS Abdominal pain domain correlated significantly with all QOLRAD domains in most language versions, and with SF-36 Bodily pain in all versions. QOLRAD domains correlated significantly with the majority of SF-36 domains in most versions. Both questionnaires were able to differentiate between patients whose health status differed according to symptom frequency and severity. Conclusion: The psychometric characteristics of the different language versions of the GSRS and QOLRAD were found to be good, with acceptable reliability and validity. The GSRS and QOLRAD were found to be useful for evaluating dyspeptic symptoms and their impact on patients' daily lives in multinational clinical trials. © 2008 Kulich et al; licensee BioMed Central Ltd.