A large umbrella review of research on complementary, alternative and integrative medicine (CAIM) for autism has found no high-quality evidence that any of the approaches improves core or associated autism symptoms, while also reporting that safety outcomes are rarely evaluated. The researchers also launched a public online platform intended to make the evidence easier to explore.
Researchers from Paris Nanterre University, Paris Cité University and the University of Southampton have published what they describe as a broad quantitative synthesis of evidence on complementary, alternative and integrative medicine (CAIM) approaches used in autism.
Published in Nature Human Behaviour, the study pooled evidence from 248 meta-analyses drawn from 53 meta-analytic reports, covering 19 types of CAIM interventions. Across those meta-analyses, the authors report that the underlying evidence base spans more than 200 controlled clinical trials and over 10,000 autistic participants.
The review concludes that no CAIM intervention has high-quality evidence supporting its efficacy for core or associated autism symptoms. While some approaches showed potentially positive signals in pooled analyses, the authors say those findings were typically supported by low or very low certainty evidence, often reflecting small study sizes and methodological limitations.
The authors also highlight gaps in harm reporting. They report that safety outcomes—such as acceptability, tolerability and adverse events—have rarely been evaluated across the CAIM literature they examined, and they call for future studies to incorporate stronger safety monitoring.
The paper notes that use of CAIM is common among autistic people, citing research indicating that up to 90% report having tried at least one such approach at some point.
Professor Richard Delorme, head of the Child and Adolescent Psychiatry Unit at Robert Debré Hospital in Paris and a co-author, said many families and autistic adults seek alternatives in hopes of benefit without unwanted side effects, but stressed the need to rely on evidence from rigorous randomized trials before deciding whether to try these interventions.
The study’s first author, Dr. Corentin Gosling of Paris Nanterre University, said the team chose an umbrella review approach to assess the overall state of evidence across many treatments rather than focusing on individual trials.
Alongside the review, the researchers launched a free online evidence platform, EBIA-CT, intended to help users navigate and interpret results across interventions and outcomes. The platform is available at https://ebiact-database.com.
Professor Samuele Cortese, an NIHR Research Professor at the University of Southampton and a co-senior author, said the findings underscore why treatment decisions should not rely on isolated studies, particularly when the underlying evidence is low quality.
The research was funded by France’s Agence Nationale de la Recherche (ANR).
