Vocabulary Intervention for EFL/ESL Learners with Autism Spectrum Disorder - A Systematic Review

Abstract

Vocabulary acquisition is essential for language development among learners with autism spectrum disorder (ASD), yet evidence on effective instructional interventions in EFL/ESL contexts remains limited. This systematic literature review, guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology, synthesizes empirical evidence on vocabulary interventions for EFL/ESL learners with ASD. Thirteen studies published between 2010 and 2026 were selected from ScienceDirect, Taylor & Francis, Sage Publications, and SpringerLink. The review examines instructional approaches, intervention effectiveness, methodological rigor, and conceptual gaps through thematic analysis. Findings indicate that visual supports, repetitive practice, contextualized learning, multimodal engagement, and technology-assisted interventions can enhance vocabulary acquisition, learner engagement, and vocabulary retention. However, the evidence is constrained by small sample sizes, short intervention durations, and methodological inconsistencies. Limited research on long-term vocabulary generalization, functional language use, and diverse educational contexts further highlights the need for rigorous investigation. The review recommends longitudinal research, comparative intervention designs, and contextually responsive strategies that address individual cognitive and sensory differences. These findings provide a foundation for developing inclusive and sustainable vocabulary instruction for EFL/ESL learners with ASD and provide practical guidance for teachers, researchers, and educational institutions seeking effective and inclusive language interventions in practice.