We have identified 3 studies of holding therapy used on autistic people published in English-speaking, peer-reviewed journals.
The three studies (Lindt, 1988; Welch and Chaput, 1988; Welch 1989) included a total of 14 children and all reported positive benefits.
There are significant methodological issues with the research studies identified to date, meaning that the quality of the evidence is extremely poor.
One is a case study of a single child. The other two are small case series undertaken by/with the creator of the intervention, Martha Welch.
For a comprehensive list of potential flaws in research studies, please see ‘Why some autism research studies are flawed’