Irritable Bowel Syndrome Outcome Study

Irritable bowel syndrome (IBS) is a condition which affects the large intestine, with symptoms that include varying degrees of abdominal pain, bloating, constipation and diarrhea. Medications and lifestyle changes are generally prescribed for IBS, but medical treatments for the full range of symptoms are inadequate. Cognitive behavior therapy (CBT), a psychological treatment where therapists teach patients how to use behavioral skills to manage IBS and relieve unresolved symptoms, has been associated with improvements in symptom severity and quality of life in other clinical trials. However, CBT has certain economic and feasibility limitations that prevent the therapy from being incorporated into routine clinical settings.

The Irritable Bowel Syndrome Outcome Study (IBSOS) sought to address the limitations of standard therapist-administered CBT by developing an effective self-administered version of the treatment method. IBSOS participants were randomized into one of three treatment groups and underwent four weeks of symptom monitoring. One group received the standard ten sessions of clinic-based CBT, one group received four sessions of minimal-contact CBT, and the remaining group received four sessions of supportive counseling and education without any prescribed behavior changes. Following the symptom monitoring phase, patients underwent treatment and follow-up phases. Assessments were regularly conducted during the study and the results were evaluated between the groups.