Objective: Health-related quality of life (HRQOL) affects outcome in chronic diseases such as inflammatory bowel disease (IBD). The inflammatory bowel disease questionnaire (IBDQ), a disease-specific HRQOL questionnaire, can define changes in health status in IBD, but simple instruments are needed for daily application. The present study proposed to develop a short version of the IBDQ, the SIBDQ, for community physicians.
Methods: Using data from a clinical trial in 149 patients with Crohn's disease, 10 items were selected (by forward stepwise regression) that best explained the variance of the IBDQ or dimensional scores (bowel, systemic, social, emotional). The validity, reliability, and responsiveness of the SIBDQ were then assessed in 150 different patients with Crohn's disease and 45 with ulcerative colitis. All scores were reported with a 7-point scale (1 = poor HRQOL, 7 = optimum HRQOL).
Results: Mean SIBDQ scores were similar (p = 0.22) in Crohn's patients among 14 participating centers at study entry. Mean scores were lower in active Crohn's disease (range 4.00-4.92) than inactive disease (range 4.67-5.83; p = 0.0015). In active ulcerative colitis, the mean SIBDQ was 4.79 +/- 1.17 compared to 5.90 +/- 0.80 (p = 0.0006) in inactive disease. The SIBDQ explained 92% and 90% of the IBDQ variance in Crohn's disease and ulcerative colitis, respectively. In patients with stable Crohn's disease, the test-retest reliability coefficient was 0.65 and Crohnbach's alpha was 0.78, indicating good reliability. In patients with Crohn's disease who relapsed during follow-up, the mean SIBDQ decreased by -0.93 + 0.55 (p = 0.001).
Conclusion: The SIBDQ is valid, reliable, and able to detect meaningful clinical changes in HRQOL that might occur in the office setting.