This supplementary report to the New Zealand Autism Spectrum Disorder Guideline describes a systematic review which aims to provide an evidence-based summary of research published in or beyond 2004 relating to gastrointestinal problems for children and young people with autism spectrum disorder (ASD) so as to update the evidence considered in the guideline.
Also reported are revised and new recommendations pertinent to the topic developed by the Living Guideline Group following consideration of the reviewed evidence. These revisions have been incorporated into the 2nd edition of the Guideline, published in 2016, available at New Zealand Autism Spectrum Disorder Guideline.
Some researchers have targeted gastrointestinal symptomatology as a means of investigating hypothesis about the aetiology of ASD, and as a rationale for employing (unproven) treatments for core symptoms of ASD. These issues are beyond the scope of the current review update. The reader is referred to the New Zealand ASD Guideline for a comprehensive account of evidence and recommendations relating to treatments, including complementary and alternative dietary interventions.