A novel, mental-imagery based, psychological intervention for anxiety in people with mild to moderate intellectual disability: co-development and initial testing

Hewitt, Olivia Mary ORCID: 0000-0002-6393-2388 (2026). A novel, mental-imagery based, psychological intervention for anxiety in people with mild to moderate intellectual disability: co-development and initial testing. University of Birmingham. Ph.D.

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Abstract

Background: People with intellectual disabilities experience anxiety disorders at a higher rate than the general population. However, there is a lack of evidence-based accessible interventions for this population. Mental imagery-based interventions are used to treat anxiety disorders within the general population but have not been systematically explored within this client group.

Aims: This project’s aims included: (1) To synthesise the literature about the abilities of people with intellectual disabilities to engage with mental imagery (the generation, maintenance, inspection, and transformation of mental images), and the role of mental imagery within existing psychological interventions for this population (Study 1); (2) To review and synthesise the literature around inclusive research in health and social care with people with intellectual disabilities, to synthesise the roles co-researchers play in such research, and capture their experiences of engaging in inclusive research (Study 2); (3) To explore the phenomenology of mental imagery in people with intellectual disabilities, in order to understand what factors facilitate or hinder the development and use of mental imagery in this population, and to consider the implications of these in terms of developing a psychological intervention (Study 3); (4) To co-develop an anxiety intervention using a mental imagery approach for people with mild to moderate intellectual disabilities (Study 4); (5) To conduct initial testing and refinement of the intervention in NHS settings, and to assess acceptability (Study 5).

Method: A mixed methods approach was used including systematic reviews of the literature (Study 1 and 2). A qualitative study was conducted and results from both verbal interviews, and creating an image using collage and drawing, were analysed and synthesised using Interpretative Phenomenological Analysis (Study 3). The framework of Experience Based CoDesign was adapted to co-develop the psychological intervention (called Co-MAID) alongside stakeholders and people with intellectual disabilities. This process was evaluated using semi structured interviews and analysed using Template Analysis (Study 4). Initial testing of the intervention was conducted with six participants recruited from NHS clinical services. This was evaluated using Single Case Experimental Design and semi structured interviews were conducted with participants and their supporters to assess the acceptability of the intervention (Study 5).

Results: Study 1 systematically reviewed 41 papers of variable quality and designs, finding that people with intellectual disabilities can engage with mental imagery, with appropriate adaptations. Facilitators and barriers to using mental imagery were identified. Study 2 synthesised 17 papers covering a diverse range of health and social care topics. People with intellectual disabilities were involved across multiple methodologies and research tasks. Study 3 analysed qualitative verbal and visual data using Interpretative Phenomenological Analysis to demonstrate that people with intellectual disabilities experience rich, detailed mental images across all sensory modalities. Study 4 employed Experience Based Co-Design to identify and implement numerous intervention adaptations, improving the accessibility and acceptability of the intervention. Participants engaged fully with EBCD, finding it enjoyable and valuable. Study 5 reported results of initial testing in NHS services, with good adherence (five participants completed the intervention with 92.6% session attendance). Template analysis revealed positive experiences with participants reporting improved mood. Three participants (50%) demonstrated reliable change on the primary anxiety measure, meeting clinically significant change criteria.

Conclusion: People with intellectual disabilities can engage with mental imagery interventions and work as co-researchers to develop psychological interventions. Further research with larger samples and controlled designs is required to establish the feasibility of a randomised control trial leading to a Phase III trial.

Type of Work:

Thesis (Doctorates > Ph.D.)

Award Type:

Doctorates > Ph.D.

Supervisor(s):

Supervisor(s)	Email	ORCID
Langdon, Peter E.	UNSPECIFIED	orcid.org/0000-0002-7745-1825
Larkin, Michael	UNSPECIFIED	orcid.org/0000-0003-3304-7000
Steel, Craig	UNSPECIFIED	orcid.org/0000-0002-1643-516X
Gray, Kylie	UNSPECIFIED	UNSPECIFIED