Translation and Cultural Adaptation of Irritable Bowel Syndrome-Quality of Life Questionnaire for Iranian Population

گوارش، مجله انجمن متخصصين گوارش و كبد ايران

دوره 14 - شماره Supple.1

Article Type: Original Article
Abstract: Introduction: Assessing quality of life of patients with Irritable Bowel Syndrome (IBS) is of great importance in clinical researches and practice. Previous attempts on validation of the IBS quality of life instruments for Iranian population had some methodological inadequacies.We aimed to cross-culturally adapt and validate the Persian version of the Irritable Bowel Syndrome-Quality of Life questionnaire (IBS-QOL-P) for Iranian IBS patients through a standard linguistic validation method. Method: The IBS-QOLwas translated into Persian and culturally adapted following the principles provided by the Translation and CulturalAdaptation working group.Asample of 109 IBS patients completed the IBS-QOL-P, IBS-Symptom Severity Scale (IBS-SSS), and HospitalAnxiety and Depression Scale (HADS). One-week retest was performed on a random sub-sample of 30 patients. Internal consistency and test-retest reliability were assessed using Cronbach’s alpha and intraclass correlation coefficient (ICC), respectively. To analyze discriminant validity, the IBS-QOL-P and its subscales were correlated to IBS-SSS and HADS. Responsiveness to treatment was assessed in 42 IBS patients who underwent a 10-wk cognitive-behavioral therapy (CBT) trial. Change scores in the IBS-QOL-P were then correlated to changes in IBS-SSS and HADS scores. Results: The internal consistency and test-retest reliability were acceptable for all of the IBS-QOL-P domains with Cronbachs’ alpha coefficients and ICCs ranging from 0.68 to 0.90 and from 0.77 to 0.91, respectively. Discriminant validity was supported by the presence of correlations of the IBS-QOL-P total and subscales scores (except sexual domain) with IBS-SSS and HADS scores. The IBS-QOL-P was responsive to treatment as demonstrated by significant correlations between change scores in the IBS-QOL-P with changes in IBS-SSS and HADS scores after CBT trial. Conclusion: The IBS-QOL-P appears to be a reliable instrument with sufficient psychometric requirements to assess the disease-specific HRQL and the effect of treatments on HRQL in Iranian IBS patients with Persian language.