Online Parent-Mediated Intervention for Preschool Autistic Children: A Randomized Controlled Trial

Autism spectrum disorder (ASD) is characterized by persistent deficits in social communication and interaction, accompanied by restricted and repetitive patterns of behavior. Parent-mediated interventions are recommended as an evidence-based approach for promoting early developmental outcomes by enabling parents to implement intervention strategies during everyday interactions with their children. The purpose of this randomized controlled trial was to evaluate the effectiveness of an eight-week online group-based parent-mediated intervention based on Naturalistic Developmental Behavioral Intervention (NDBI) principles for preschool autistic children compared with a waitlist control group. Families were randomly assigned to either the intervention group or the waitlist control group. Parents in the intervention group participated in weekly online group sessions that included psychoeducation, therapist coaching, video-based feedback, and structured home practice, whereas families in the waitlist control group continued their usual educational services during the study period. Participants in the intervention group were additionally assessed eight weeks after completion of the intervention to evaluate the maintenance of treatment effects. The primary outcome was the between-group difference in children's social communication skills, measured using the Social Communication Checklist-Revised (SCC-R), from baseline to immediately after the intervention. Secondary outcomes included between-group differences in parental psychological distress measured by the Depression Anxiety Stress Scales-21 (DASS-21) and parental broad autism phenotype characteristics measured by the Broad Autism Phenotype Questionnaire (BAPQ), as well as the maintenance of treatment effects in the intervention group at the eight-week follow-up. The study also examined demographic and clinical factors associated with improvements in children's social communication skills following the intervention.

Inclusion Criteria: Children aged 2 to 5 years with a confirmed diagnosis of Autism Spectrum Disorder (ASD) according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). ASD diagnosis confirmed by an experienced child and adolescent psychiatrist. At least one parent or primary caregiver willing to participate in all intervention sessions. The same parent or primary caregiver available to participate throughout the study. Parents willing to complete all study assessments. Families agreeing not to initiate another structured parent-mediated intervention during the study period. Written informed consent provided by the participating parent or legal guardian. Exclusion Criteria: Presence of genetic, neurological, or significant sensory disorders (e.g., hearing impairment) that could substantially affect child development. Participation in another structured parent-mediated intervention during the study period. Inability of the participating parent to attend the intervention sessions or complete the study assessments.