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Capturing learning from public involvement with people experiencing homelessness to help shape new physiotherapy research: Utilizing a reflective model with an under‐served, vulnerable population

Abstract Introduction People experiencing homelessness (PEH) have poorer health than housed people but face barriers accessing care and being involved in research. As an often‐ignored group, their contribution to help shape research that is for and about them is essential, as it can strengthen the research proposal, in turn facilitating research and outcomes that are relevant to this vulnerable group. Methods Six people with experience of homelessness attended a PPI consultation aided by Pathway, a UK homeless peer advocacy charity, which coordinates an ‘Experts by Experience’ group. We present reflections on conducting PPI with PEH that informed the development of a physiotherapy research proposal. Kolb's Experiential Learning Cycle guided reflections across four stages: (1) describing the PPI experience; (2) reviewing and reflecting on the PPI experience; (3) learning from the PPI experience; and (4) planning and trying out learning. Results Reflections highlighted the importance of: working closely with an advocacy organisation and leader to reach under‐served people; the diversity of experiences; using familiar venues, contingency and budget planning; flexibility and ‘allowing time; talking less; listening more’; planning for early and ongoing PPI, and the potential of mobile ‘one‐off’ PPI outreach models to reach vulnerable groups. Conclusion Kolb's Experiential Learning Cycle aided team reflection on feedback from PEH, which helped refine and strengthen a physiotherapy research proposal. The project was unfunded. However, a reflective model helped maximize learning and impact including for future PPI and research. The novel application of Kolb's Experiential Learning Cycle provided structure, facilitated reflection and enhanced individual and collective learning and may benefit capturing learning from PPI with other vulnerable populations. Patient or Public Contribution We highlight how a PPI consultation with people with experience of homelessness helped shape a funding proposal. Additionally, the reflections of the experts by experience team leader are included.


| Aims and objective
This reflective case study shares individual and collective learning from patient and public involvement (PPI) activities focussed on the development of a mixed-methods research funding proposal investigating accessibility, acceptability, and the need for physiotherapy services for people experiencing homelessness (PEH). We reflect on how involving vulnerable and under-served PEH in a new physiotherapy study helped inform both the funding proposal and future research planned by team members. We aim to impart learning to help inform researchers undertaking PPI with other underserved and vulnerable groups.

| PEH and their health
A person experiencing homelessness can be defined as anyone who has no home 1 and includes people identified in official United Kingdom (UK) statistics as 'legally homeless' and the 'hidden homeless' (those out of sight in squats, hostels, Bed and Breakfasts or staying with friends). In England alone, the most extreme forms of homelessness 2 have increased year on year since 2010 3 with the latest estimates standing at 280,000 people. 4 During the 2020 pandemic the UK government announced the 'Everyone In' scheme, housing around 29,000 rough sleepers in emergency accommodation 5 and guaranteed residential tenants protection from eviction during this period. 6 Both may have positively impacted homelessness statistics.
However, economic challenges resulting from the pandemic may increase homelessness when such interventions no longer apply.
PEH have poorer health than housed people, often experiencing a 'tri-morbidity' of mental and physical ill-health, substance misuse 7 and early mortality. 8 The combination of ill-health, coupled with insecure living arrangements, can make PEH some of the most vulnerable in our society.
The incidences of musculoskeletal, cardiorespiratory problems and brain injury [9][10][11] are greater amongst PEH than in the general population. Care of these conditions is the core area of physiotherapy practice, with rapid access recognized as vital in preventing more severe or long-term health problems. 12 Despite a high prevalence of these conditions amongst PEH, research shows they have difficulty accessing National Health Service (NHS) physiotherapy. 13 General practitioner (GP) referral is the main access route to NHS physiotherapy care. However, around 33% of people sleeping rough are not registered with a GP, compared with only 2% of the English general population. 14 Barriers to registering and attending primary care include frequently moving areas, a chaotic lifestyle and lack of transport. 14 These challenges may explain why PEH are regarded as being under-served by current healthcare provisions.

| The UK Research Governance Framework: Involving vulnerable people in research
Researchers aiming to improve the health of vulnerable and underserved groups must ensure their voices are heard throughout the research process. Current UK guidance states that health and social care research must provide an environment where patients, service users and the public '…are given, and take, the opportunity to participate in health and social care research and to get involved in its design, management, conduct and dissemination, and are confident about doing so'. 15

| Patient and public involvement in research with vulnerable, under-served populations
Patient and public involvement (PPI) in research is defined as '… research being carried out "with" or "by" members of the public rather than "to", "about" or "for" them'. 16 The founding principle being, people who are affected by research have a right to have a say in how it is designed, undertaken and disseminated. 17 An earlier version of UK research guidance explicitly referenced the importance of involving PEH in research. 18 Vulnerable members of the public also include children and young people, older people, people from low socioeconomic backgrounds, prisoners, those living with chronic illnesses, people from black and minority ethnic backgrounds and asylum seekers. 19 Such groups tend to have greater health care needs than the wider population 20 and face multiple barriers in engaging with healthcare services, further compounding health problems. 14 They are also frequently excluded from involvement to help shape and deliver research. 21 'Under-served groups' is a term adopted recently by the NIHR's INCLUDE guidance 22 in preference to others (e.g. 'hard to reach') that erroneously imply the lack of inclusion is due to the fault of the members of these groups. There is no single definition of underserved groups, but characteristics common to them include: lower inclusion in research; high healthcare burden unmatched by the volume of research designed for the group and differences in how they respond to or engage with healthcare interventions compared to other groups, with research often neglecting to address these factors. 22 We use the term 'under-served' to refer to PEH in terms of their access to both health services and research opportunities, as it is a useful reminder that healthcare and research communities need to engage better to provide appropriate services and opportunities for these groups. Additionally, their views on improving the accessibility of services are likely to go unheard.
Researchers must explore opportunities to undertake PPI when planning and prioritizing research about health services for vulnerable, under-served groups, and reflect on those opportunities to help support wider learning about how involvement works, for whom and when. 23

| Reflexivity in PPI work
Developed against a backdrop of debates around measuring PPI impact, 24 there is recognition that reflecting on patient and public activities can help capture researchers' 'rich and valuable' subjective accounts of the value and impacts of PPI. 23 It is argued that reflexivity forms one of the fundamental principles underlying the evaluation of PPI. 25 Staley and Barron 23 suggest reporting of PPI should enable researchers to 'tell the story' of what happened, '…where the researchers started, what they learnt from their conversations with the public…' and '…what changed as a result…'. 23 Reflecting on PPI activities may help researchers to learn from, and impart their PPI story. The NIHR UK Public Involvement Standards encourages researchers to reflect on the PPI they undertake though no guidance is given regarding how. 16 Previous reports of reflections of PPI have adopted 'critical reflection' techniques using written and annotated diaries employed in different degrees by various members of the research team, including: researchers 26 only; researchers and public contributors reflecting separately 27 and, collective reflections of the entire team. 28 Techniques drawing on 'models' of reflection have also been applied to learning from PPI activities. For example, a reflective model developed by Marks-Maran and Rose, 29 which comprises four components (the incident; reflective observation; related theory and future action) was used to reflect on the PPI experiences of a research team developing a stroke study. 30 However, we chose The Experiential Learning Cycle 31 to reflect on our PPI activities due to its established utility within physiotherapy and familiarity within the team.

| Context
This project was led by J. D., a physiotherapist with extensive clinical experience in homelessness healthcare. It was designed to inform a proposal for research exploring physiotherapy services for PEH. Research priorities in healthcare for PEH have recently been identified using a stakeholder event. However, it did not involve people with lived experience of homelessness. 32 The challenges of involving PEH in PPI and research have recently been discussed, highlighting the complications of paying appropriate fees to people in receipt of welfare benefits, or the difficulty some people might have in committing to a project of long duration (perhaps over many years). 33 These insights further show the importance of our work to help to fill a knowledge gap. We describe two experiences pertinent to this reflective case study.
First, undertaking a PPI consultation with PEH and secondly, undertaking the process of reflection.

| Undertaking a PPI consultation with PEH
A research idea and question were formulated building on previous research looking at access to mainstream NHS physiotherapy for PEH. 13 It was important to discuss the new ideas with people who had experienced homelessness, to establish whether the research question was relevant to them and to gain insights regarding the proposed recruitment, data collection, analysis and dissemination methods.
The research team engaged with Pathway, a leading UK homeless peer advocacy charity to help reach people with lived experience of homelessness. 35 Pathway runs Experts by Experience (EbE), a group led by and for people who have experienced homelessness.
EbE aims to influence healthcare providers, commissioners and researchers to ensure services and research are designed to best meet the needs of people experieincing homelessness. 36 The EbE team leader (who also had lived experience of homelessness) helped recruit EbE members to attend a PPI consultation to help inform the funding proposal.
The PPI consultation was held in a room used by Pathway, led by Further reflection occurred after the (unsuccessful) NIHR funding outcome was known. The consultation notes and recording were revisited by the team who were keen that, despite the unsuccessful funding outcome, learning from the PPI session should not be lost.
The latter focus was on how the PPI consultation helped inform team members' subsequent PPI thinking and research activities. We recorded our collective learning, recognizing this may be transferable to PPI with other under-served or vulnerable groups. We individually followed the four phases of the Experiential Learning Cycle 31 to aid reflections. J. D. collated and summarized key topics, which were circulated within the team for further debate and clarification, until finally a consensus was reached on key collective learning outcomes. He suggested that those given the opportunity to tell their story benefitted when they felt heard, but with that comes vulnerability.
He recommended that such vulnerability should be acknowledged and valued by the research team.

| DISCUSSION
The PPI session and subsequent reflections reported in this paper demonstrate the value of reaching vulnerable, underserved groups to inform new research, which affects them and the potential value of the reflection and learning process for teams undertaking PPI with similar groups. Vulnerable groups, such as PEH, are known to struggle to access healthcare services like physiotherapy. 13 It is also vital they are not overlooked by teams planning research that affects them; something we hope our reflections help address.
A recurring observation from the collective reflections was the value of working with a third-party advocacy organisation and community leader to reach a diverse group of PEH. The research team did not have direct contacts with PEH, nor resources to build links on the ground, so it offered pragmatic advantages for engaging potentially people from a socially disadvantaged group, an important issue highlighted in a related systematic review. 40 As others have noted, involving public contributors early and undertaking reflections together may help foster a collaborative approach whereby relationships and trust are built and maintained between researchers and public contributors, 41,42 helping address power differentials. 43 Collaborating with a community representative external to the research team has also been recommended elsewhere 42,43 as this provides a useful 'buffer' should public contributors have concerns that may be difficult to raise directly with the research team. The 'guardian role' adopted by the EbE Team Leader in our project may have helped foster 'ethically conscious' 44 PPI being undertaken, by helping our vulnerable group of people with experience of homelessness feel safe and able to speak openly. Involving members of the community of interest as advocates (or who adopt 'protective roles') may help the conduct of more ethical PPI from the outset and help reach a broader more diverse population; something the EbE leader felt had been achieved in this project.
Holding the PPI consultation at a venue hosted by pathway may have afforded a well-known and safe environment, enabling attendees to discuss their views and experiences openly. As other commentators have stressed, budgeting to enable public contributors to attend a venue and to cover out-of-pocket expenses is crucial, 42,43,45,46 and was offered to our attendees. Previous studies have undertaken different approaches to reflecting on PPI primarily at the end of their studies. 30,41,43 We undertook ours in-depth early on at the design stage. We recommend the reflective practice and learning taking place at the earliest opportunity (as well as throughout the study) to maximize impact on shaping the proposal and delivery of research. Reporting of PPI rated highly by funding reviewers, but which may ultimately be unfunded should still be routinely reported so that learning can be maximized and not lost.
A strength of this paper is the novel application of Kolb's Experiential Learning cycle 31 to aid reflection, and to our knowledge, this is the first time Kolb has been used to reflect on and evaluate PPI. Using the four stages of Kolb 31 to facilitate reflections on PPI was a pragmatic and relevant approach for a team that included physiotherapy researchers since the model is widely used in physiotherapy education and clinical practice. 49 By including all members of our research team and an EbE in the reflection phase, and supplementing this with team discussions, we aimed to mitigate the power imbalances that often exist in research teams via dialogue.
A limitation of the Experiential Learning Cycle model is that it may fail to account for how 'reflection in action' can be utilized as a learning tool. 50 Therefore, we advocate supplementing the model with team reflections (including members of the public) that are dialogical rather than discursive, to consider collective thoughts on the shared PPI experience. This paper demonstrates the benefit of including an EbE in the reflection process and the value it brought to the teams' understanding of the experience.

| CONCLUSION
The individual and collective PPI reflections and learning reported in this paper were inspired by an early-stage PPI session with a vulnerable group, with the aim of informing a research funding application. This paper demonstrates the value of undertaking PPI with vulnerable, under-served groups such as PEH, and how individual and team reflections using an existing model have the potential for enhancing the learning from PPI undertaken with other vulnerable groups. The planned physiotherapy research project was ultimately unfunded. However, by using a theoretical model to reflect on the early design stage PPI process we have gone some way to optimize learning both individually and collectively from the PPI experience.
Reflecting on and getting the most out of PPI activities is an ethical imperative, even when projects are not funded. 43 We concur that '…a reflection cycle can be usefully employed as a tool to structure ongoing dialogue about the motivations, contributions and experiences of researchers and members of the public when they work together to develop and conduct health research studies'. 30