Table 1 Recommendations for improving inclusion in clinical trials and clinical research

Research staff

All research staff should receive cultural competency training

There was evidence that culturally sensitive study staff improved the recruitment and retention of diverse populations

Training should be given to staff at all levels so that cultural competency is present across research organisations. To foster an open environment where learning is continuous, it is also recommended that staff are encouraged to reflect on mistakes and lesson learnt [51]. Role-play may also be helpful as part of the training [44].

Increase recruitment of staff from under-served groups

To better ensure that teams represent the communities that trials serve

This is also an important part of ensuring a culture that has inclusion at the forefront of its values.

Communication

Personalise communications as far as possible

There was strong evidence that people preferred to be seen as individuals

This could include, for example, having a consistent point of contact rather than having contact with lots of different individuals and sending personalised mailings such as birthday cards and thank you letters.

Have video calling as a contact option

Some under-served groups require or prefer a visual option for communications, e.g. deaf individuals

This may also benefit other groups that rely on visual cues for communication.

Alternative language options available for all communications

There was strong evidence that availability of non-English communications greatly assisted under-served groups

This relates to both written and verbal communications, and so bilingual staff or translators may be required. Also, consider non-foreign language options for other under-served groups, e.g. sign language and braille.

Consider offering community outreach

Outreach to community leaders, groups, and providers was highly effective in several studies

Research teams could consider offering outreach (e.g. community events/meetings) to increase the participation of under-served groups.

Include social proof where possible in communications

Social proof and validation were important enablers

Social proof could include, for example, testimonials. This may also help with building trust.

Offer extended office hours

A lack of out-of-office availability was a consistent barrier

This could potentially cover evenings or weekends and could be delivered via telephone, email, or instant messenger chat. Under-served groups will be best placed to advise on how this could support them best.

Community

Establish a diverse community advisory panel for ongoing input into the research process

Closing the gap between researchers and under-served groups was consistently highlighted as an effective strategy

It is vital that the voices of under-served groups are heard. Building relationships with these groups and consulting regularly with them will help to ensure that existing inequities are not perpetuated.

Education

Include education about clinical trials for the public on study websites

A lack of knowledge about and trust in trials was a recurring barrier

This could focus particularly on the importance of inclusion in clinical trials and how the research organisation is working towards that.

Feasibility and or identification

Examine demographic summary of excluded populations

Eligibility criteria may directly or indirectly exclude under-served groups

Where possible (i.e. with access to local data), researchers should compare demographic summaries of the initial target population compared with that of eligible participants so that the generalisability of results can be determined.

Encourage the use of sites with high enrollment of under-served groups

For research to be generalisable, it is key that the research goes where the need is and not only where investigators already are

This may require an initial understanding of which under-served groups are particularly relevant to the condition of interest.

Explore whether linkages with non-healthcare data sources could increase trial access for people without access to healthcare

Inability to access healthcare and/or not being part of the traditional system were barriers to accessing trials

This could include, for example, working with refugee, prison, or homeless data providers.

Consider creating a local registry of individuals from under-served groups who are interested in participating in trials

A diverse registry of people interested in participating in trials was an effective strategy

This could initially be piloted for one particular under-served group before being rolled out more widely.

Outcomes

Collect data on both sex at birth and gender identity

This was identified as an effective strategy among transgender individuals

This could also potentially benefit other under-served gender groups as well.