Literature Review

As an Accredited Exercise Physiologist, researcher and passionate autism clinician, it is important to stay up to date with relevant literature in the field. I intend to provide easy to read, concise summaries of important or relevant articles on this page. Please find below a breakdown of a recent influential paper, titled:

Prevalence of Motor Difficulties in Autism Spectrum Disorder: Analysis of a Population‐Based Cohort

Melissa K. Licari, Gail A. Alvares, Kandice Varcin, Kiah L. Evans, Dominique Cleary, Siobhan L. Reid, Emma J. Glasson, Keely Bebbington, Jess E. Reynolds, John Wray, Andrew J.O. Whitehouse

Published: 18 October 2019, International Society of Autism Research https://doi.org/10.1002/aur.2230

Background/Rationale

Motor impairment is not currently listed in the diagnostic criteria for autism, despite being a commonly considered clinical feature of autism. Motor impairments can include difficulties with planning movement, muscle tone and strength, timing and execution, balance and gait. This lack of documentation is in part, due to the lack of large-scale studies instigating motor ability in this population. Previous small studies have shown motor difficulties as high as 50% among people with autism, which is as high as other known diagnostic specifiers such as intellectual or language impairments.

In Western Australia, a population-based register of new ASD diagnoses called the WA Autism Register has been in place since 2017 (https://www.telethonkids.org.au/projects/autismregister/). This study aimed to utilise the register to collect large, population level data on motor impairment among children with a recent autism diagnosis, using a standardised assessment.

Method

All families on the register were contacted (N=5941), and those who consented to participation in the study complted the Vineland Adapative Behaviour Scale (N=2711). Of those participants, 2175 reported a motor score.

Results

Scores on the Vineland indicated that 35.4% met the criteria for motor difficulties (standard score<70), almost as prevalent as intellectual impairment (37.7%). This is astounding, considering diagnostic clinicians only report motor difficulties at a rate of 1.3%!

It was also reported that the prevalence of motor difficulties was significantly correlated with age of diagnosis (p<0.001), meaning that early diagnosis may play a key role in overcoming motor deficits.

Discussion

The study provides the largest investigation into autism and motor difficulties and demonstrates that that motor difficulties are a prevalent, and often over-looked factor related to autism spectrum disorder.

Summary by Joshua Knuiman

All credit goes to the original authors listed above.