Measuring the Health Related Quality of Life of Children With Inflammatory Bowel Disease

Introduction: Treatment and follow up of patients with Inflammatory Bowel Disease (IBD) is mainly based on clinical symptoms, laboratory tests, endoscopic and histologic findings. However these findings fail to reflect the patients' subjective experience of health. Health Related Quality of Life (HRQL) is an important outcome measure in Inflammatory Bowel Disease (IBD). We aimed to test the validity and reliability of the Anglicised PedsQlTM core module for children with IBD.

Methods: Children aged 8-18 years (N=56) who fulfilled national IBD definitions of Crohns and Ulcerative Colitis and 50 of their parents completed the self report and proxy version of the PedsQlTM core module, along with an established HRQL measure specific to IBD (IMPACT III). An assessment of disease activity was made using severity ratings for ulcerative colitis and Crohn's Disease. PedsQlTM patient and parent scores were compared to those of healthy children (N=561) and their parents (N=272) and the questionnaires psychometric properties were tested as described below.

Results: Alpha co-efficients for self and proxy report scales ranged from 0.70 to 0.94 confirming the scales' internal reliability. PedsQlTM scores showed significant correlation with scores on IMPACT (Pearson's R ranged from 0.32-0.76, P<0.05 for the different subscales) and with a rating of disease activity (e.g. Pearson's R = 0.38 and 0.30, P<0.05 for self-report and proxy report respectively on Total score) establishing construct validity. IBD patients and their parents reported significantly lower PedsQlTM scores than healthy children and parents, establishing the measure's discriminant validity. Good concordance between child and parent forms confirmed that the two reports were measuring the same construct (Pearson's R ranged from 0.68-0.84, P<0.05 for the different subscales).

Conclusion: PedsQlTM has been recommended as one of the more promising paediatric HRQL measurement systems currently available. Its advantages include brevity, the availability of age appropriate versions, and parallel forms for child and parent. Its generic core dimensions also match those described by WHO. The work reported here confirms the reliability and validity of the Anglicised measure for a group of UK children with IBD. PedsQlTM will provide a useful outcome measure for research and clinical practice involving paediatric patients with IBD.