Peer interactions in autistic children and adolescents: A systematic review.

Peer interaction plays a central role in social, emotional, and cognitive development across childhood and adolescence. For autistic individuals, difficulties in peer interaction are a defining feature and are associated with reduced participation, limited social learning, and adverse outcomes such as loneliness, rejection, and isolation. Despite its importance, the literature on peer interactions in autism remains fragmented, employing diverse measures, age groups, and study designs, with inconsistent attention to individual and environmental factors. The aim of this systematic review was to examine the quantity and quality of peer interactions among autistic children and adolescents, and to explore how peer interactions are associated with individual and contextual characteristics, including age, sex, autism severity, social skills, cognitive abilities, partner type, and emotional and behavioral factors. Electronic searches (2014-2024), supplemented by manual journal searches, identified 29 quantitative and mixed-methods studies focusing on peer interactions (excluding interventions) among school-age autistic participants. Through inductive thematic analysis, four central themes emerged: peer participation and social network centrality, interaction quality, partner type, and individual differences. Overall, autistic children and adolescents demonstrated lower peer engagement, more peripheral or isolated social positions, and lower peer acceptance compared to non-autistic peers. Importantly, findings showed substantial heterogeneity, influenced by age, autism severity, social skills, cognitive abilities, emotional factors, and partner type. These findings highlight the need for developmentally sustained, peer-based interventions that promote complex interactions, reduce isolation, and value mixed and unmixed peer interactions. Future research should employ consistent, naturalistic measures and diverse samples to capture variability in peer experiences.