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22/11 HSDR Implementing the Mental Capacity Act in practice (Mental Capacity Assessments) supporting information


Published: 19 January 2022

Version: 1.0 - January 2022

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Closing date: 1pm on 19 July 2022

Please note: the following is intended to provide further information on the background of this call but does not constitute an exhaustive review of the literature in this area.


About two million people in England and Wales are thought to lack capacity to make decisions for themselves, supported by around six million people, including health and social care staff. Legal frameworks such as the Mental Capacity Act 2005 (MCA), which applies in England and Wales, protects the rights of people who may lack capacity to make decisions, whether temporarily or permanently.

The MCA has been in force since 2007 and its primary purpose is to promote and safeguard decision-making within a legal framework. Applying to people over the age of 16 years, a fundamental aim of the Act is to empower individuals to make their own decisions wherever possible, for example in safeguarding, end of life care or consenting to medical treatment, while also enabling decisions to be made in a person’s best interest when they are assessed as lacking capacity. The MCA is accompanied by a code of practice which is currently being reviewed. It is anticipated that in 2022 the Deprivation of Liberty Safeguards (DoLS) will be replaced with the Liberty Protection Safeguards (LPS) to provide protection for people who are - or who need to be - deprived of their liberty in order to enable their care or treatment, and who lack the mental capacity to consent to their arrangements.

A review by the House of Lords in 2014 concluded that the legal framework of the MCA was generally robust and that there was widespread support among stakeholders for the core principles. However, the review noted that the implementation of the MCA had been poor. It stated that the empowering ethos of the Act had not been widely implemented and that a number of improvements were needed, including the quality of capacity assessments and supported decision-making. The review also found that clinical judgments and resource-led decision making predominated over the wishes of individuals, alongside prevailing cultures of risk-aversion and paternalism.

Putting people at the centre of their own health and care is a major component of the NHS Long Term Plan recognising that ensuring choice and sharing control can improve care outcomes, help patients make decisions that are right for them, and require professionals to work differently. The National Institute for Health and Care Excellence (NICE) has published a quality standard on decision-making and mental capacity, to contribute to improvements in how people are enabled to make decisions about their own lives and participate as fully and effectively as possible in a decision made in their best interests.

Identified research need

NICE guideline NG108 sets out the need for research to evaluate the effectiveness of training on improving mental capacity assessment practice, to evaluate the effectiveness of assessment tools that are compliant with the MCA and to understand the components of an effective MCA assessment.

Evidence has highlighted several aspects in which assessments are being carried out that are not compliant with the MCA. These relate to: general lack of understanding of the Act; failing to conduct the two-stage process; the use of general capacity assessments versus decision-specific assessments; judgements of capacity being based on an individual’s diagnosis rather than assessing their capacity; and a lack of consideration for cultural, ethnic and religious factors that may impact an individual’s decision-making. There remains a paucity of evidence evaluating capacity assessment tools that are compliant with the MCA, in terms of their impact, acceptability and application in practice.

The James Lind Alliance Priority Setting Partnership on Adult Social Work identified a research priority on whether the MCA has been embedded into practice, and the impact on people using services and carers. Their work found uncertainties about social care practice in using the MCA to support older people and people with learning disabilities.

There is limited research into social work and social care practice which explicitly explores how capacity is assessed and decision making is supported. Research has highlighted variability in practice by healthcare professionals, particularly doctors who often perform MCA assessments in secondary and tertiary settings, and healthcare professionals’ lack of confidence in their ability to undertake these assessments.

Differences in experiences of conducting capacity assessment between professional groups and settings emerged from a recent large-scale survey, however concerns about the effects of “undue influence” by third parties was reported across professional groups, and there is very little in the literature about how such effects are identified and mitigated.

Reviews of existing evidence have identified a need for improved and research-based training strategies to embed the application of the MCA in practice. There is evidence to suggest that the Act has positively impacted person-centred care and human rights. However, a need has been highlighted for more effective interventions to improve health and social care professionals’ knowledge and confidence in implementing capacity assessment, as well as research to explore the impact of the MCA on those affected by it, including family members and carers, in order to offer a more holistic insight into experiences of the MCA.

While some training resources for use of the MCA do exist, there remains a lack of evidence in respect of their application and impact in practice, with most of the training being developed for specific staff and patient groups, without reference to other training materials. NICE also highlighted that whilst research into MCA assessment often refers to training and support for practitioners, very few studies have specifically explored this area.

Research proposed for this call should draw on workplace learning theory and evidence-based workplace training and educational interventions that can realistically be implemented across different health and social care settings. Health and Social Care Delivery Research (HSDR) Programme has previously funded the development and evaluation of training interventions for healthcare staff in different settings, such as the CHAT study or the CLECC programme. Other relevant work in the HSDR portfolio includes evaluation of communication training for hospital staff working with people with dementia and understanding ‘What works in dementia education and training’ as well as wider work with some parallels in research on implementation of do not attempt cardiopulmonary resuscitation (DNACPR) policies in clinical practice.

An ongoing interdisciplinary research programme, Mental Health and Justice, led by King’s College London, is exploring the concepts of metacognition and insight in relation to mental capacity and will produce guidance for frontline professionals on decision-making and mental capacity.