Abstract
INTRODUCTION: Autism spectrum disorder (ASD) is a prevalent neurodevelopmental disorder. Parents of children with ASD often have a higher level of affiliate stigma, which impacts their physical and mental health, family relationships and social functions. Nowadays, a variety of assessment tools are available for measuring this stigma, but they have many limitations. This systematic review aims to critically appraise the measurement properties of instruments used to assess affiliate stigma in parents of children with autism and help researchers and healthcare professionals make more appropriate choices when using these tools. METHODS AND ANALYSIS: This protocol adheres to the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols guidelines. We will search five English databases (ie, PubMed, Web of Science, ScienceDirect Online, Embase and Cochrane Library) and four Chinese databases (ie, SinoMed, China National Knowledge Infrastructure, Wanfang Database and VIP information) from the databases' inception to 30 September 2025. Eligible studies will evaluate instruments measuring affiliate stigma in parents of children with autism, including self-report and observer ratings. The psychometric properties assessed will include reliability, validity, responsiveness, interpretability and clinical utility. Only primary quantitative studies published in peer-reviewed journals will be included. The search will have no limitations on language or time. Two researchers will independently carry out data extraction and quality assessment, with disagreements resolved through consensus or a third researcher. The consensus-based standards for the selection of health measurement instruments risk of bias checklist and the Grading of Recommendations Assessment, Development and Evaluation approach will be used to evaluate each measure's methodological quality and overall strength of evidence. ETHICS AND DISSEMINATION: As this research constitutes a systematic review of pre-existing published data, formal ethics committee approval is deemed unnecessary in accordance with international research ethics guidelines. The synthesised findings will be submitted for publication in a rigorously peer-reviewed academic journal and presented at pertinent scientific conferences to ensure transparent knowledge dissemination within the academic community. PROSPERO REGISTRATION NUMBER: CRD420251043478.