The Gluten Free Diet: Assessing Adherence in a Pediatric Celiac Disease Population

BACKGROUND: A strict, lifelong, gluten-free diet (GFD) remains the sole treatment for celiac disease (CD). The assessment of adherence to the GFD in pediatric studies is often based on self-report and visual analogue scales which lack proven validity. We sought to compare parental-report of GFD adherence to expert registered dietitian (RD) assessments, the best available standard. METHODS: Parents of children with biopsy-proven CD scored their adherence to the GFD on a five-point Likert scale similar to that used in previous pediatric CD studies. Each family was then evaluated by an RD expert in CD management who conducted a comprehensive and standardized assessment and scored the family's adherence. The agreement between parents and the RD was assessed using paired t test and intraclass correlation coefficient (ICC) based on their scores. RESULTS: One hundred twenty-two children and their families participated in the study, with a median of 32 months on a GFD. Excellent adherence (score 5 out of 5) was attributed to 60.5% of the sample by the RD. The parents scored adherence higher than the RD by an average difference of 0.41 scale points (95% CI, 0.28-0.54; P < 0.001). The agreement between parents and the registered dietitian was poor (ICC = 0.21). CONCLUSION: Reliance on self-report through Likert scales for GFD adherence overestimates adherence and misses opportunities for patient and family education. Approximately 40% of children with CD have ongoing gluten exposure, highlighting the need for regular assessment by an RD expert in the GFD to identify education and counselling needs for children with CD.