Research on psychosocial interventions for dementia demonstrates increased rigour and robustness. However, if we are to influence practice, beyond results from randomised controlled trials, a variety of types and sources of evidence is needed. The Medical Research Council (MRC) framework offers a valuable guide for developing, evaluating and implementing complex interventions, to facilitate integration of research into practice. There is limited knowledge of how researchers design, evaluate and implement psychosocial intervention studies in dementia, using the MRC framework. This scoping review aims to: (1) identify the methodological and methods trends, use and gaps in the development, evaluation and implementation of psychosocial interventions for dementia, and (2) determine if and how the MRC six core elements were considered and applied in studies.

Six databases (Ovid MEDLINE, Embase, PsycINFO, CINAHL, Web of Science, Cochrane Library) will be searched for studies published from 2015 (when MRC process guidance was published) to 2025. Identified deduplicated citations will be imported into Covidence software, where up to 40% of title/abstracts will be double screened by independent reviewers. ASReview will be used to rank articles by relevance, with a stopping criterion of 250 consecutive irrelevant articles. Full texts will be reviewed by a single reviewer and those excluded will be checked by a second reviewer. Data extraction will include study aim/objective (ie, to develop/adapt; test feasibility/pilot; evaluate; implement); methodology and methods applied; information on which MRC six core elements were considered (yes/no), and if so, how they were addressed (ie, qualitative details). A narrative synthesis, alongside graphical representations (eg, table/bar charts/histograms), will be used to synthesise findings on methodologies and methods mapped onto the MRC framework.

This secondary analysis scoping review does not require ethics approval. Results will be disseminated through peer-reviewed publication(s), seminars, webinars, conferences, postgraduate dementia programmes, blogs, commissioner briefings and social media. The findings will provide a state-of-the-art overview of current practices; advance methods/methodology such as informing a Delphi consensus study on appropriate research approaches; and guide researchers in application of the MRC framework to widen the scope of dementia care evidence for practice improvements.

Submitted to Open Science Framework https://doi.org/10.17605/OSF.IO/S56NQ.

To explore how health and social care professionals (HSCPs) in the UK conceptualise and respond to cognitive dysfunction in depression, including its potential long-term implications for brain health and dementia risk.

A qualitative, semi-structured interview study. Data was analysed using a code-book approach to thematic analysis.

The study was conducted in the UK, with HSCPs from diverse professional backgrounds including general practitioner, psychology, psychiatry, mental health nursing, psychological well-being practitioner and occupational therapy. A total of 12 participants were recruited via purposive and convenience sampling.

Three master themes were developed, (1) Cognitive dysfunction in depression, (2) Persistence of cognitive dysfunction and (3) Depression and dementia risk. HSCPs expressed challenges in screening for cognitive dysfunction in depression, particularly as dementia-related screening tools were used which may not be sensitive enough to detect depression-related cognitive deficits. A number of potential explanations were reported as to why cognitive dysfunction may persist after mood symptoms have lifted. These included substance misuse, role of education, neurological conditions and depression as a prodrome to dementia. Depression as a potential risk factor for poorer brain health in the context of dementia risk reduction was not communicated in clinical settings to service users. Barriers to communication included lack of evidence base on depression as a potential risk factor, as well as lack of guidance on communication practices in the context of mental health issues.

Cognitive dysfunction in depression is a complex phenomenon and remains under-explored. Challenges around identification and screening indicate a need for validation studies of cognitive screening measures for use in mood disorders, as well as pilot, acceptability and feasibility trials of interventions targeting cognitive functioning in mood disorders. Mixed-methods research is warranted to understand whether guidance on communicating depression as a risk factor for brain health is required and/or justified.