Symptoms of heartburn and their impact on health-related quality of life (HRQL) are often evaluated in clinical trials. When a questionnaire is translated into a new language, a linguistic validation is necessary but not sufficient unless the psychometric characteristics have been verified. The aim of the study is to document the psychometric characteristics of the Polish translation of the Gastrointestinal Symptom Rating Scale (GSRS) and quality of life in reflux and dyspepsia (QOLRAD) questionnaire. One hundred and thirty-five patients with symptoms of heartburn (mean age: 44, SD = 14.6; females % = 60.7) completed the Polish translation of GSRS, the heartburn version of QOLRAD, the Short-Form-36 (SF-36) and the Hospital Anxiety and Depression (HAD) scale. Seventy patients were scheduled for a second visit a week later to complete the GSRS and QOLRAD again. The internal consistency reliability of GSRS ranged from 0.58 to 0.88 and of QOLRAD from 0.84 to 0.95, and the test-retest reliability of GSRS ranged from 0.34 to 0.63 and of QOLRAD from 0.51 to 0.74. The relevant domains of the GSRS, "reflux", "abdominal pain" and "indigestion", and all QOLRAD domain scores significantly correlated. GSRS domains "abdominal pain" and "indigestion" were related to all SF-36 domains. All QOLRAD domains significantly correlated with all SF-36 domains.
Conclusions: the psychometric characteristics of the Polish translations of GSRS and QOLRAD were found to be good, with satisfactory reliability and validity. The test-retest reliability of the GSRS "reflux" domain was however not optimal.