Validation of child-adapted short scales for measuring gastrointestinal-specific avoidance and anxiety

Abstract

Aim: To validate child-adapted shortened versions of the Irritable Bowel Syndrome-Behavioural Responses Questionnaire (IBS-BRQ; short scale denoted BRQ-C) and the Visceral Sensitivity Index (VSI; short scale denoted VSI-C) for children with functional abdominal pain disorders (FAPDs). Methods: A child psychologist supervised by a child gastroenterologist was responsible for shortening the scales (BRQ-C, 11 items; and VSI-C, 7 items). Then, a sample of 89 children aged 8–12 years with FAPDs was used in the validation. Construct validity was assessed with correlations. Measures included gastrointestinal symptoms, quality of life, pain intensity and anxiety. Also, internal consistency, test–retest reliability, administration time and factor structure were assessed. Results: Internal consistency for the BRQ-C and the VSI-C was α = 0.84 and α = 0.80, respectively. Correlations with related scales were similar between child-adapted scales and original scales, indicating construct validity equivalence. Correlations between short scales and original scales were high. Mean administration time was reduced by 47% (BRQ-C) and 42% (VSI-C), compared with original scales. Test–retest reliability was r = 0.72 for BRQ-C and r = 0.83 for VSI-C. BRQ-C had two factors (Avoidance and Bowel control). VSI-C had a unifactorial structure. Conclusion: The BRQ-C and the VSI-C were found to be time-saving, reliable and valid for children with FAPDs.