Quality of life measures in irritable bowel syndrome.

Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder with significant morbidity, resulting from the interaction of physiologic, psychological, social, cultural and behavioral factors. In view of this complex interaction, and in the absence of a measurable biological index of disease, health-related quality of life (HRQoL) has emerged as an ideal measure for use in clinical trials and outcome studies. This article discusses the relevance of HRQoL measurement in IBS and its definition. It then explores the research methodology in HRQoL and describes how global measures and generic HRQoL instruments have been used in IBS. Finally, the IBS-specific HRQoL measures are described in detail, with an emphasis on their development, content and validation.