Abstract
RATIONALE: Children with neurodevelopmental disorders such as attention-deficit hyperactivity disorder (ADHD), autism, developmental language disorder (DLD), intellectual disability (ID), and social (pragmatic) communication disorder (SPCD) experience difficulties with social functioning due to differences in their social, emotional and cognitive skills. Previous systematic reviews have focussed on specific aspects of social functioning rather than broader peer functioning and friendships. OBJECTIVE: To systematically review and methodologically appraise the quality and effectiveness of existing intervention studies that measured friendship outcomes for children with ADHD, autism, DLD, ID, and SPCD. METHOD: Following PRISMA guidelines, we searched five electronic databases: CINAHL, Embase, Eric, PsycINFO, and PubMed. Two independent researchers screened all abstracts and disagreements were discussed with a third researcher to reach consensus. The methodological quality of studies was assessed using the Cochrane Risk of Bias Tool for Randomised Trials. RESULTS: Twelve studies involving 15 interventions were included. Studies included 683 children with a neurodevelopmental disorder and 190 typically-developing children and diagnosed with either autism or ADHD. Within-group meta-analysis showed that the pooled intervention effects for friendship across all interventions were small to moderate (z = 2.761, p = 0.006, g = 0.485). The pooled intervention effect between intervention and comparison groups was not significant (z = 1.206, p = 0.400, g = 0.215). CONCLUSION: Findings provide evidence that some individual interventions are effective in improving social functioning and fostering more meaningful friendships between children with neurodevelopmental disorders and their peers. Effective interventions involved educators, targeted child characteristics known to moderate peer functioning, actively involved peers, and incorporated techniques to facilitate positive peer perceptions and strategies to support peers. Future research should evaluate the effectiveness of friendship interventions for children with DLD, ID and SPCD, more comprehensively assess peer functioning, include child self-report measures of friendship, and longitudinally evaluate downstream effects on friendship.