Systematic Review and Meta-analysis of Gross Motor Impairment in Autism and Relationships to Social Impairment

• In Event: Poster Session 13
  In Poster Session: PS 13 Topic - Developmental Disabilities

Abstract

Background: Gross motor ability is tied to profound differences in how children experience and interact with their social world (Karasik, Tamis-LeMonda, & Adolph, 2011; Bar-Haim & Bart, 2006). A growing literature in autism spectrum disorder (ASD) indicates that autistic individuals exhibit gross motor impairment, which may contribute to the development or maintenance of the core social deficits that characterize ASD (Leonard & Hill, 2014; West, 2019). However, due to substantial heterogeneity across studies, it is currently unclear which gross motor skills are impaired in ASD, when and for whom these differences emerge, and whether motor and social impairment are related.

Objectives: Use meta-analysis to synthesize knowledge about gross motor deficits and their relationship to social deficits in ASD and test potential moderators of these effects.

Method: Two meta-analyses were conducted. Study 1 compared gross motor ability between autistic and neurotypical (NT) individuals. Study 2 examined the correlation between gross motor and social impairment in ASD. A systematic search identified articles on gross motor behavior in ASD, which were screened for inclusion by two independent raters. Study 1 included 114 articles (N=4,173 autistic and N=2,941 NT individuals). Study 2 included 21 articles (N=654 autistic individuals). Group difference (Study 1) or correlational (Study 2) effects were extracted and coded for methodological and phenotypic moderators, including gross motor skill domain, muscle group, social skill domain, gross motor/social measurement method, age, IQ, and sex. Robust variance estimation models were used for analyses and compared to mixed-effects models to ensure reliability of findings.

Results: Study 1 demonstrated a significant overall gross motor skills deficit in ASD (Hedges’ g=-1.02, p<0.001) that was robust to methodological and phenotypic variation. This difference was moderated by gross motor skill domain, measurement method, and muscle group, but not age, IQ, or sex. Object control was found to be the most impaired skill (g=-1.39), and clinical assessment of motor skills yielded the largest effects (g=-1.26), while goal-directed reaching (g=-0.54) and tasks recruiting the lower extremities (g=-0.51) yielded the smallest effects. Nevertheless, deficits were significant for every domain, method, and muscle group. Study 2 revealed a moderate significant overall correlation between gross motor and social deficits in ASD (r=0.27, p< .0001), with no significant moderators.

Discussion: We identified a large overall group difference in gross motor skills in ASD. This was significant across all investigated moderators, demonstrating that autistic individuals exhibit a pervasive deficit in gross motor skills independent of age, sex, or IQ. Impairment was greatest in the object control domain, consistent with findings that motor skills requiring perception-action coupling are particularly impaired in ASD (Whyatt & Craig, 2013). Furthermore, gross motor impairment was significantly positively associated with social impairment for autistic individuals, indicating that motor deficits appear to be tied to the core social symptoms of ASD. Considered alongside literature on NT children, results support the importance of gross motor behavior for both typical and atypical social development. Further longitudinal and intervention research is needed to test the causality and directionality of the relationship between gross motor and social development.

Authors

• Leah Wang, University of Pennsylvania
  Presenting Author

• Victoria Petrulla, Florida International University
  Non-Presenting Author

• Casey Joan Zampella, Children's Hospital of Philadelphia
  Non-Presenting Author

• Rebecca Waller, University of Pennsylvania
  Non-Presenting Author

• Robert Schultz, Children's Hospital of Philadelphia
  Non-Presenting Author