Health Related Quality of Life in Iranian Patients With Irritable Bowel Syndrome: Reliability and Validity of the Persian Version of the IBS-QOL

BACKGROUND Irritable bowel syndrome (IBS) is a gastrointestinal disease that is accompanied by pain, diarrhea, constipation and abdominal bloating. Hence, IBS has a major effect on patients' quality of life. OBJECTIVES The present study aimed to examine validity and reliability of the Persian version of the IBS-QOL questionnaire in Iran. PATIENTS AND METHODS The original 34 items of the IBS-QOL were translated from English into Persian through a structured procedure for the translation and cultural adaptation of the original English IBS-QOL into Persian. Ninety one patients who had GI symptoms but did not have any organic diseases (including 70 IBS patients diagnosed by Rome II criteria) were recruited from teaching hospitals Shiraz University in Iran and completed a Persian version of the IBS-QOL along with a Persian version of Room ΙΙ and IBS severity index (IBSSI). RESULTS Our findings showed that the IBS-QOL has excellent convergent and acceptable discriminant validity. All domains had Cronbach's alpha greater than 0.7 except health worry. Seventy patients who were diagnosed as IBS by the Room ΙΙ had significantly lower scores in the IBS-QOL than those who were not (FBD) (43.7 ± 20.1 vs. 73.4 ± 14.9, P < 0.01). Age, sex, education or marital status did not affect scores in measuring the quality of life. CONCLUSIONS In conclusion, the Persian version of the IBS-QOL provided a well-defined measure of QOL in IBS patients with high validity and reliability that is an appropriate measure to use in further IBS clinical studies in Iran.