Efficacy of Applied Behaviour Analysis in Reducing Stereotypic Behaviours of Children with Autism Spectrum Disorder in Lagos State

This study empirically evaluates the efficacy of applied behaviour analysis in reducing stereotypic behaviours among children with Autism Spectrum Disorder in special education settings in Lagos State, South West Nigeria. Stereotypic behaviours, including repetitive motor movements, object manipulation, and verbal self-stimulation, represent a diagnostic feature of autism that can significantly interfere with learning engagement and social interaction. Applied behaviour analysis, with its systematic use of antecedent modification, differential reinforcement, and extinction procedures, has extensive international empirical support but remains underutilised in Nigerian special education practice. This study employs a multiple-baseline single-subject experimental design across six participants in three special schools in Lagos. Baseline and intervention data on targeted stereotypic behaviours are collected through continuous direct observation using partial interval recording. Visual analysis and effect size calculations using Tau-U are applied to assess intervention effects. The study introduces a contextually adapted applied behaviour analysis protocol with simplified implementation procedures suited to Nigerian classroom conditions. Findings are anticipated to demonstrate functional relationships between the intervention and significant reduction in stereotypic behaviour frequency across all participants. The study contributes original empirical evidence to the sparse Nigerian literature on behaviour-analytic intervention for autism, addressing a critical gap between international best practice and local implementation. Recommendations include a national applied behaviour analysis competency framework for Nigerian special educators and structured mentoring for behaviour technicians. Keywords: applied behaviour analysis, stereotypic behaviour, autism, Lagos State, single-subject design.