Sleep in Autism Across the Lifespan: A Protocol for a Cross-Sectional Survey with Nationwide Dissemination in Spain

Background: Autism spectrum disorder (ASD) is consistently associated with a high prevalence of sleep disturbances across the lifespan, with reported rates ranging from 60% to 86% depending on age and clinical characteristics. Although this issue has been widely described in the international literature, Spain currently lacks large-scale data to estimate the prevalence of sleep disturbances or to examine their relationship with factors such as age, intellectual disability, and co-occurring conditions. This study aims to estimate the prevalence and severity of sleep disturbances in individuals with autism spectrum disorder in Spain and to examine their associations with developmental stage, intellectual disability, affective symptoms, and contextual factors. Methods: This is a cross-sectional observational survey with nationwide dissemination approved by the Ethics Committee of the Universidad Católica San Antonio de Murcia. Data will be collected through an online survey (SurveyMonkey) including validated instruments: the Children's Sleep Habits Questionnaire-Autism (CSHQ-Autism) and the Sleep Disturbance Scale for Children (SDSC) for pediatric participants; the Pittsburgh Sleep Quality Index (PSQI) for adolescents and adults without intellectual disability; and the Diagnostic Assessment for the Severely Handicapped-II (DASH-II) for adults with intellectual disability. Anxiety and depressive symptoms will be assessed using the Child Behavior Checklist (CBCL) in children and adolescents and the Hospital Anxiety and Depression Scale (HADS) and DASH-II. Statistical analyses will be conducted using SPSS v22 by applying parametric or non-parametric tests according to data distribution. Conclusions: This study represents one of the first survey protocols with nationwide dissemination designed to assess sleep disturbances in individuals with ASD in Spain. The resulting findings are expected to help identify vulnerability profiles, inform public health strategies, and support the development of multidisciplinary interventions aimed at improving sleep and, consequently, the quality of life of individuals with autism and their families.