Psychometric Performance of Fatigue Scales in Inflammatory Bowel Disease.

Fatigue is very common in people with inflammatory bowel disease (IBD). Fatigue scales are important for studies testing treatments for fatigue. However, information about how well these fatigue scales measure fatigue is inadequate in IBD. In this study, we compared the how well multiple fatigue scales worked in people with IBD. We focused on scales that can be used in many different clinical populations including the Fatigue Impact Scale (FIS), the Modified Fatigue Impact Scale-IBD (MFIS), the Daily Fatigue Impact Scale (DFIS), RAND-36-vitality scales and Patient Health Questionnaire fatigue item. Scores on the three FIS, MFIS and DFIS were strongly related to each other, and these three scales generally performed well; the others did not. The FIS and MFIS-IBD were best able to discrminate between people with IBD who did and did not have ongoing disease activity.