Early Behavioral Interventions for Children and Adolescents With Autism Spectrum Disorder in Routine Clinical Care: A Systematic Review and Meta-Analysis

Public Health Significance Statement Early behavioral interventions for autism spectrum disorders in children treated in routine clinical care was found efficacious in reducing symptoms within the outcome domains adaptive behavior, cognition, communication, and socialization, with medium to large within-group effect sizes at post-treatment and follow-up. The outcome of effectiveness studies was similar to that of efficacy studies. Our findings suggest that clinicians and patients can be confident about the effectiveness of early behavioral interventions with already established efficacy when delivered in routine clinical care. As treatment effects are not lost when evidence-based treatment programs are transported from research clinics to routine clinical care, further implementation of evidence-based interventions is needed in routine clinical care for children with autism disorders. The current paper systematically reviews and meta-analyses the effectiveness of early behavioral interventions (BI) for children with autism spectrum disorder (ASD) in routine clinical care. The effectiveness of BI, methodological study quality, and moderators of treatment outcome were examined and benchmarked with efficacy studies. The quality of the evidence was assessed with the Cochrane risk of bias tool. Twenty-nine studies were included, comprising 1,422 participants. Medium to large within-group effect sizes (g = 0.76-1.27) were found post-treatment for the outcome domains adaptive behavior, cognition, communication, and socialization, with large average effect size at post (g = 0.94) and at follow-up (g = 1.08). Comparison of effectiveness and efficacy studies showed that evidence-based early BI in routine clinical care yielded effects comparable to university research settings. The limitations include potential language and publication bias. The findings support evidence-based behavioral treatments delivered in routine clinical care as efficacious in reducing ASD symptoms. PROSPERO registration: ID CRD42020212833.