Table 3 Summary of barriers and facilitators to conducting trials involving adults with impaired capacity

Making trial design decisions

∙ Complexity of the legal frameworks governing trials involving adults lacking capacity

∙ Lack of access to relevant expertise in trial teams

∙ Lack of effective training and information about conducting trials with adults who lack capacity

∙ Context-specific recruitment issues (e.g. lack of consultees/legal representative in some settings, role of gatekeepers)

∙ Pressure of recruitment targets and timescales which do not take account of the additional time required to recruit adults lacking capacity

∙ Lack of resources (e.g. research nurse time) to meet the additional resources required

∙ Lack of appropriate and agreed outcome measures for participants with cognitive impairment and their proxies

∙ Experience and familiarity with trials with adults lacking capacity to consent

∙ Availability of additional data (qualitative, feasibility) to inform the design and conduct of the trial

∙ Flexibility and use of adaptive strategies (e.g. allowing remote contact and consent from consultees and legal representatives)

∙ Feedback from funders and reviewers which recognises the importance of the inclusion of adults lacking capacity and supports their inclusion

Navigating ethical approval

∙ Lack of knowledge and understanding by RECs and research teams about the legal provisions for adults lacking capacity and how they are implemented in practice

∙ Differences in the legal provisions between nations (e.g. between England & Wales and Scotland) and the impact of dual applications and multiple sets of trial documents

∙ Lack of provision for conducting emergency non-CTIMP research in Scotland under AWI

∙ Inconsistency in REC reviews (both between and within RECs) and inaccuracies in advice/requirements

∙ Having an established relationship with a REC who have previously reviewed trials involving adults who lack capacity by the research team

∙ Effective communication with RECs who are able to offer knowledgeable advice to trial teams

Informing and supporting the participant

∙ Complex and lengthy Participant Information Sheets that are not cognitively or linguistically accessible

∙ Lack of access to timely translation services that are appropriate for people with cognitive impairment who do not have English as a first language

∙ Availability of accessible trial information (e.g. easy-read, pictorial, brief summary version)

∙ Involvement of family and carers to support the person with cognitive impairment to make a decision about research participation

Assessment of capacity to consent

∙ Requirement to conduct assess capacity remotely which is more challenging and unfamiliar

∙ Lack of access to background information held in clinical records

∙ Seeking the views of others who are familiar with the person (e.g. family, usual carers)

∙ Access to expertise on communication and assessing capacity (e.g. Speech & Language Therapist)

Involvement of alternative decision-maker

∙ Reliance on care team to identify and approach family members

∙ Gatekeeping or lack of engagement from families and care team

∙ Uncertainty around the legal and ethical role of alternative decision-makers

∙ Challenging process of decision-making when the person’s wishes and preferences are unknown

∙ Flexible consent arrangements (e.g. telephone consultation, verbal consent/agreement)

∙ Established processes for involving alternative decision-makers (e.g. prospective list of care team members able and willing to act as consultee/legal representative)

Revisiting consent and consultation

∙ Participant is discharged, transferred or dies before consent can be sought (e.g. deferred consent or recovered capacity)

∙ Reliance on remote contact only during a trial (e.g. postal follow-up only)

∙ Regular communication and establishing a rapport with the participant and their care team

∙ Prospective planning for changes in capacity (e.g. prospectively obtaining family contact details, ongoing involvement of family/carer)