Quality of life assessment in inflammatory bowel disease (IBD):: German version of the Inflammatory Bowel Disease Questionnaire (IBDQ-D; disease-specific instrument for quality of life assessment) -: First application and comparison with international investigations

Background: Health-Felated quality of life (HRQOL) is an important outcome-parameter in health research and care. The aim of the working group Quality of Life in the Competence Network Inflammatory Bowel Disease (IBD; in the original German: "Kompetenznetz chronisch entzundliche Darmerkrankungen") is to generate instruments for assessment of HRQOL and its implementation as standards in clinical trials, health care and research in IBD. Methods: The Inflammatory Bowel Disease Questionnaire (IBDQ) is an international validated disease specific instrument for HRQOL-assessment. A German version of the IBDQ was elaborated and tested in 415 outpatients with Crohn's disease (CD, n = 306) and ulcerative colitis (UC, n = 109). The aim of the study was to compare the results of HRQOL-assessment (IBDQ-D) with international investigations, to correlate HRQOL results with disease activity and to preform a pretest of psychometric properties. Results: International data suggest that the IBDQ-D is a suitable instrument for HRQOL-assessment in CD and UC. For both disease a statistically significant negative correlation with disease activity was found. Tested psychometric properties do not suggest that a revision of the IBDQ-D is required. The IBDQ-D offers the HRQOL-assessment as an primary or secondary outcome in clinical trials in IBD in Germany.