top of page

The Significance of "No Significant Difference"

Brief Overview and Critique of Involved Study

In the scientific community, there has been discussion for a while regarding the possibility of a connection between Autism Spectrum Disorder (ASD) and gastrointestinal infections. This debate was actually the start of Andrew Wakefield starting the myth of vaccines causing autism (they don’t!) A team of researchers has recently concluded that there is no significant difference in the overall prevalence of GI symptoms in children suffering from ASD. In fact, an editorial article within the Expert Review of Gastroenterology and Hepatology, a world-renowned magazine, indicates that an article in the journal Pediatrics cited a study by Ibrahim et al. for evidence when discussing this matter.

However, there are several flaws and limitations in Ibrahim’s study which could have contributed to an incorrect conclusion. Therefore, it is quite important to consider some of these aspects of the study. For example, the editorial mentions that Ibrahim’s study was retrospective (using past information), suggesting that many of the medical records that were utilized may have been incomplete. Furthermore, it was not clearly indicated whether children with conditions such as Asperger’s were included in the group of children that were deemed to have been diagnosed by ASD. In regards to the diagnosis, many of the children seemed to have not been properly diagnosed with ASD but rather just some of the associated symptoms such as a delay in speech and language.

Additionally, the study poorly grouped many different GI problems into one main category. For reference, the infamous condition of gastroesophageal reflux disease is considered to be far more prevalent in children with ASD but was unfairly grouped with far less worrisome symptoms such as “vomiting” in the study. Also, researchers involved in this study did not list any pieces of information about how long GI symptoms persisted (or the severity of it for that matter) in the experimental group, made-up of ASD children, and the control group. Furthermore, researchers neglected to take into consideration details such as different types of diets or dietary medications involved in the different children that were used as subjects. Many clinicians have suggested children go on special diets such as “keto” or “Whole 30” and there is currently no information on whether it has affected autism symptoms.


The editorial by the Expert Review of Gastroenterology and Hepatology accurately discusses the grave implications of conducting a study with the degree of flaws such as the study by Ibrahim and his team of researchers. It is never sufficient to make a medical conclusion based on one study. However, inaccurate conclusions for children of any condition, not just ASD, can affect their lives. The children who have ASD may have had serious GI symptoms that should have been addressed. Additionally, faulty studies can lead to conclusions that mask important details. For example, it is mentioned in the editorial that “...43% (nine out of 21) of children with autism spectrum disorders had altered intestinal permeability (leaky gut) compared with 0% of controls (zero out of 40)” (Brown and Lewis, 2010). The problem with altered intestinal permeability is quite serious but could have been easily shadowed by Ibrahim’s conclusion that there is no significant difference.

Article Utilized Primarily

Brown, Amy C, and Lewis Mehl-Madrona. “Autoimmune and gastrointestinal dysfunctions: does a subset of children with autism reveal a broader connection?.” Expert review of gastroenterology & hepatology vol. 5,4 (2011): 465-77. doi:10.1586/egh.11.46


Ibrahim SH, Voigt RG, Katusic SK, Weaver AL, Barbaresi WJ. Incidence of gastrointestinal symptoms in children with autism: a population-based study. Pediatrics 124, 680–686 (2009).

14 views0 comments

Recent Posts

See All
bottom of page