Inclusion of Participants With Limited English Proficiency in Autism Research.

Individuals with autism spectrum disorder (ASD) and limited English proficiency (LEP), defined as having limited ability to read, write, or understand English, may experience disparities in quality of care and healthcare outcomes. However, little research has described methods and practices for including participants with LEP in ASD research studies. This literature review study investigated (1) the prevalence of LEP inclusion in U.S. research about ASD, (2) the languages included, and (3) the communication methods between research teams and participants with LEP. Using the Covidence Systematic Review Software, we completed a two-round screening of 1007 studies published between 2013 and June 2025 in four major autism journals: Autism, Autism Research, Journal of Autism and Developmental Disorders, and Research in Autism Spectrum Disorders. We limited the sample to U.S.-based original research involving human subjects with ASD and/or their caretakers. Eligible studies were reviewed further to extract relevant study information (e.g., participant demographics, study type, communication methods, and inclusion of LEP participants). Only 61 (19%) among the 326 eligible studies explicitly mentioned the inclusion of participants with LEP and provided information about their inclusion. Other studies may have included LEP participants but did not report their inclusion in the publication. The most common language included was Spanish. Results showed that the most used oral and written communication methods involved communication with, and translation of study materials by a bilingual research team member. The results suggest that LEP participants were underrepresented in ASD research, and future research is needed to advise more inclusive healthcare practices and policies for children and families.