Comparison of Executive Function Skills between Patients with Cerebral Palsy and Typically
Developing Populations: A Systematic Review and Meta-Analysis
Background: Children with CP show deficits in executive function compared to their
typically developing peers, based on the majority of the available evidence. However,
the magnitude of these deficits, as well as the proportions of the shortfalls in the
three main components, have not yet been examined. This is the first meta-analysis
to synthesize evidence on the magnitude of differences between patients with cerebral
palsy (CP) and typically developing populations in different components of executive
function skills (working memory, inhibitory control and cognitive flexibility), and
thus makes recommendations on which areas of executive functioning are in greatest
need of intervention. Methods: We conducted a systematic literature search of four
databases for studies that measured executive functions in these two groups until
31 August 2023. We calculated the standardized mean difference (Hedges’ g), an average
effect size overall, and for the three components of executive function skills separately,
we used several moderator analyses, including methodological differences between the
primary studies. Results: Fifteen articles were included in the meta-analysis. The
average mean difference in executive functioning overall was large (g+ = −0.82). Furthermore,
large significant differences were found in working memory (g+ = −0.92) and inhibitory
control (g+ = −0.82) and a moderate difference was identified in cognitive flexibility
(g+ = −0.57). In addition, results of moderator analyses reveal the importance of
a rigorous matching of control group participants and CP patients. Conclusions: The
results demonstrate a severe impairment in all executive functions among CP patients
compared to typically developing peers, which do not decrease over time.