Data mining the ScanBrit study of a gluten- and casein-free dietary intervention for children with autism spectrum disorders: behavioural and psychometric measures of dietary response.

We previously reported results based on the examination of a gluten- and casein-free diet as an intervention for children diagnosed with an autism spectrum disorder as part of the ScanBrit collaboration. Analysis based on grouped results indicated several significant differences between dietary and non-dietary participants across various core and peripheral areas of functioning. Results also indicated some disparity in individual responses to dietary modification potentially indicative of responder and non-responder differences. Further examination of the behavioural and psychometric data garnered from participants was undertaken, with a view to determining potential factors pertinent to response to dietary intervention. Participants with clinically significant scores indicative of inattention and hyperactivity behaviours and who had a significant positive changes to said scores were defined as responders to the dietary intervention. Analyses indicated several factors to be potentially pertinent to a positive response to dietary intervention in terms of symptom presentation. Chronological age was found to be the strongest predictor of response, where those participants aged between 7 and 9 years seemed to derive most benefit from dietary intervention. Further analysis based on the criteria for original study inclusion on the presence of the urine compound, trans-indolyl-3-acryloylglycine may also merit further investigation. These preliminary observations on potential best responder characteristics to a gluten- and casein-free diet for children with autism require independent replication.