Background
In 2021, three Community Health and Wellbeing Worker (CHWW) pilot programmes were implemented in Westminster (London), Calderdale (West Yorkshire), and Bridgewater (Warrington). Based on the Brazilian primary care system, these proactive community outreach and care navigation interventions marked the first efforts to implement this novel service in England. Guided by the theorised model—as described in academic literature [1-8] and communicated through professional networks involving the model’s principle theorist, Dr Matthew Harris—each site aimed to recruit workers from the locality, integrate them into the primary care system with training in basic health promotion, and support them to conduct proactive outreach in patches of around 150 households on an ongoing basis. This approach corresponded to what has been described as the CHUI (“chewie”) principles: Comprehensive, Hyperlocal, Universal, and Integrated. The overarching objective was to help residents access timely support to improve their health and wellbeing, without differentiation based on age, need, or any other criteria, by connecting them with primary care and other community services.
Despite seeking to implement the same model, there were significant differences between the three programmes, stemming from the routes through which they were commissioned and the circumstances under which they were implemented, as well as the distinct regional and cultural characteristics of the three settings.
- Westminster’s pilot was commissioned by the local authority, which recruited four workers and a service manager, and delivered on a housing estate in central London. The CHWWs were hosted by a GP practice close to the estate, with access to practice patient records and clinical oversight from a GP and implementation lead who facilitated integration of the workers into practice workflows. The programme also received significant input from researchers from Imperial College London, who provided guidance on implementation and conducted research into the pilot’s impact on healthcare service uptake [9]. in 2023, the programme was recommissioned by Healthcare Central London (HCL), a GP federation, and expanded, with the enlarged CHWW team now being hosted by Voluntary and Community Sector (VCS) providers in multiple settings across Westminster.
- Calderdale’s pilot was commissioned by the CCG/ICB[a], under NHS England’s Community Mental Health Transformation (CMHT) policy framework, and hosted by Healthy Minds, a well-established mental health charity. The largest of the pilots, Calderdale recruited 11 CHWWs, who worked across nine diverse communities throughout the borough. Distinct from the other programmes, Calderdale’s CHWWs were not formally integrated into primary care, a decision driven by the charity’s concerns about community trust and data privacy, as well as the challenges of data sharing and interoperability. Nonetheless, the workers were supported to develop collaborative connections with primary care providers locally. The pilot was discontinued in September 2024, after the borough’s partnership board reached a consensus that there was insufficient commitment to recommission the programme.
- Bridgewater’s pilot was commissioned and hosted by an NHS Community Healthcare Foundation Trust, a provider of specialist healthcare services, including community dental services, health visiting, and community matrons. The trust recruited six CHWWs (over the course of the pilot) who worked in a small community in Warrington. The CHWWs had access to patient records, once residents consented to participate, and received clinical oversight from the programme manager, with additional training and oversight support from other trust teams. Despite initial interest from the Primary Care Network (PCN) in co-hosting the programme, the pilot remained operationally separate from general practice for most of its duration; however, the workers established collaborative relationships with individual practice staff. In September 2024, the PCN agreed to trial a targeted outreach programme, using the CHWWs, across a much wider geographic footprint. This marked a significant shift in the service model and so was not captured within the process evaluation. Following a review of the modified service, the PCN did not wish to recommission the programme and it was discontinued in March 2025.
To understand how the CHWW programme was implemented in each setting and to identify contextual factors (barriers and facilitators) influencing delivery and uptake, I conducted a comparative case study process evaluation. This research was necessary because interventions like the CHWW service are complex, requiring close evaluation to identify what makes them effective—or not—in different settings and under different circumstances. Understanding the dynamic interplay between the intervention and its unique local context—including existing services, organisational cultures, funding environments, and policy landscapes—is critical for success.
Methods
Using a mixed-methods approach, data were collected through participant observation of steering group and oversight meetings, interviews (with implementors, service providers, system leaders, and service users), focus groups (with CHWWs), and from secondary data sources, including routinely collected productivity data, service reports, and CHWW-authored case studies. Data analysis was structured using the Consolidated Framework for Implementation Research (CFIR), which aided identification of contextual determinants across five domains (Innovation, Outer Setting, Inner Setting, Individuals, Implementation). Data synthesis involved cross-case comparison to identify patterns and develop explanatory programme theories about implementation of the CHWW model.
Results
The combined results of the three process evaluation case studies are presented in Table 1, detailing factors that acted as facilitators and barriers to the CHWW programmes across the three settings.
Table 1. Combined facilitators and barriers to the implementation of the CHWW programme in three settings.
| Facilitators | Barriers |
| Innovation | |
| The model aligned with local policy priorities and service development goals: In Westminster, to improve connections between patients and general practice. In Calderdale, to improve community wellbeing, prevention, and cross-sector collaboration (CMHT policy objectives), and develop neighbourhood hubs (borough-level objective).In Bridgewater, to implement proactive outreach and develop the healthcare workforce. | Some senior leaders and stakeholders expressed uncertainty about the desirability of the model without locally-relevant evidence of impact.In Calderdale, the host organisation leadership questioned the appropriateness of the primary care integration principle, particularly regarding the workers’ access to patient records, leading to non-integration, a significant deviation from the CHWW model. |
| Outer Setting | |
| Connections with other pilot sites, developed through the NAPC and CHWW community of practice, offered operational support, guidance, and a unified purpose. Local partnerships and wellbeing networks, involving NHS, local authorities, and VCS organisations, created opportunities for collaboration and awareness raising about the model. | Scepticism regarding the service among some senior stakeholders (principally in Calderdale and Bridgewater), notably those in the PCN, resulted in unwillingness to recommission the pilot.In Calderdale, NHS England’s expectations regarding CMHT impact metrics were ill-matched with the CHWW model. |
| Inner Setting | |
| Westminster: a GP service champion facilitated training and integration of CHWWs into practice workflows; the service manager did likewise in the local authority; both provided pastoral support.Calderdale: the host organisation fostered a supportive and nurturing environment valued by the CHWWs; the team collaborated and trained with other services in the organisation.Bridgewater: the trust was well-resourced for implementation and provide training, shadowing, and collaboration opportunities. | Westminster: low awareness about the service initially impeded integration into the GP practice; local authority resourcing and recruitment processes were slow, delaying aspects of the service.Bridgewater: Complex oversight and programme development processes delayed project initiation. |
| Individuals | |
| CHWWs in all settings were characterised by personability, empathy, willingness to learn, and possessing local connections.Residents appreciated the programme’s proactive and personalised support.Implementation leads possessed clinical training and/or experience managing community support and outreach services.In Westminster, connections with high level opinion leaders were leveraged to raise the programme’s profile, aiding sustainability. | In Bridgewater, strategic responsibilities diverted the programme manager away from team oversight, negatively impacting morale and team cohesion. |
| Implementation | |
| Effective community engagement and relationship building: Perseverance and a sustained presence within fixed geographical areas helped establish trust and connections with residents. Proactive outreach methods, including community coffee mornings, canvassing in pairs, scheduling pre-arranged appointments, and using marketing materials like postcards, improved service visibility and resident engagement. Structuring home visits with clear time limits, defined boundaries, and encouraging residents to document their concerns facilitated more productive interactions. Strong inter-service collaboration and care navigation: Collaborative partnerships with VCS providers, social prescribing link workers, and GP practices were crucial for effective care navigation. Access to clinical data systems (e.g., Electronic Health Records) further enabled navigation and signposting activities. Robust data practices and organisational learning: Developing data collection tools based on feedback and needs. Collaborative data workshops involving academic research teams, helped refine data collection processes. CHWW case studies provided rich insights into their work and were used effectively in stakeholder communications. Supportive team dynamics, culture, and CHWW empowerment: Attentive and supportive supervision, readily available peer support, and clear safeguarding procedures enhanced CHWW resilience and effective teamworking. A positive team culture, cultivated through frequent and open communication, the sharing of skills and knowledge, and an accessible and open programme manager, was highly beneficial. CHWWs valued working with autonomy and flexibility, having a clear vision for their role, and feeling a sense of equality and common purpose. Effective project management: Proactive measures, such as responding to low uptake and planning for a controlled closure of the service, where applicable, demonstrated good project oversight. | CHWW role clarity, scope, and empowerment issues: A lack of clarity regarding the role’s scope could lead to uncertainty around purpose and objectives. CHWWs experienced frustration over their limited influence on wider systemic issues affecting residents (e.g., housing).Perceptions of inadequate compensation were a concern for some CHWWs. Challenges in resident engagement and service uptake: Difficulties were encountered in engaging certain resident demographics (e.g., single, employed individuals).Overall service uptake rates were low in some settings, attributed to a lack of systematic follow-up with residents who initially declined participation (Bridgewater).CHWW safety and operational support concerns: Some CHWWs expressed concerns about their personal safety during visits. Lone working devices provided for safety were often deemed unreliable. Data collection and performance measurement issues: Standard productivity measures were often felt to underrepresent the full scope of CHWW effort and impact. Self-reported wellbeing measures used were neither validated nor practically useful for providing meaningful insights into resident outcomes. Operational and management challenges: The novelty of the programme presented multiple operational challenges, requiring concerted effort to retain adherence to, and enhance understanding about, the CHWW model. Requirements to provide regular update reports, whilst maintaining day-to-day oversight of the programme, generated a substantial administrative burden for programme managers. |
Discussion
This summary report details key findings and cross-cutting themes from the three CHWW pilot programmes. The full reports (to be published) incorporated a wide range of data, including routinely collected productivity data, to assess the reach of the programmes (the number of residents approached and supported) and the nature of the support provided, alongside detailed accounts of service user and service provider experiences of engaging with and delivering the service, respectively. The findings, which are summarised and discussed below, have broader import beyond the specific pilot contexts and form the basis of a number of recommendations detailed at the end of this discussion.
Implementation facilitators
Evidence from the diverse experiences of the three pilot programmes demonstrated that the CHWW model was fundamentally feasible to implement and generally acceptable to service users and the workforce, capable of identifying and addressing unmet need through proactive outreach. Several key factors consistently facilitated implementation success. Firstly, strong, visible leadership and dedicated service champions within host organisations were crucial, particularly individuals able to ‘span boundaries’—navigating different organisational cultures and priorities to secure buy-in and resources, as exemplified by the Westminster implementation lead. The specific context provided by the host organisation significantly shaped success, demonstrating the importance of ‘fit’ between the host’s culture, resources, and mission. For instance, the nurturing charity culture in Calderdale fostered team resilience, while Bridgewater’s NHS setting provided access to established training infrastructure and safeguarding expertise. Furthermore, robust workforce support mechanisms were essential facilitators. This included accessible, responsive supervision addressing both operational challenges and emotional demands, strong peer support networks within teams (facilitated through meetings and informal communication like WhatsApp groups), and ongoing training opportunities covering areas like safeguarding, mental health first aid, and reflective practice. Events like the data workshops in Westminster, which invited the CHWWs to provide feedback on data collection practices and tools were important for building workforce confidence, skills, and resilience, removing barriers between programme leads and CHWWs, and improving data collection and reporting. Additionally, for the implementors and programme leads, the national quarterly workshops hosted by the National Association of Primary Care (NAPC) offered structured opportunities for shared learning and problem-solving across sites, as well as for promoting adherence to the CHWW model.
Implementation barriers
Despite the programmes’ successes in engaging residents, building relationships, and delivering care navigation support, a number of pervasive challenges impacted the pilots’ trajectories and outcomes, highlighting areas needing attention for future implementation. Achieving meaningful primary care integration emerged as a universal and complex barrier. This was often hindered by practical constraints like GP time pressures, but also by deeper issues such as a lack of strategic buy-in from PCN leadership, differing organisational priorities, cultural mismatches between community-focused CHWW approaches and clinical workflows, and the inherent difficulties of effective cross-sector communication and data sharing. Alongside integration issues, operational delivery also presented difficulties. Achieving universal engagement proved challenging, requiring persistence against sometimes low response rates. CHWW safety concerns during outreach needed careful management through specific protocols and timely, responsive support, while accurately measuring the diverse activities and time investment involved in the CHWW role remained methodologically complex. Securing sustainable funding proved another critical, and ultimately decisive, challenge. This was inextricably linked to difficulties in robustly demonstrating impact and cost-effectiveness using metrics valued by commissioners within the relatively short pilot timeframes. The reliance on unvalidated wellbeing measures and process-oriented evaluation failed to provide the quantifiable impact data (e.g., reduced hospital admissions, cost savings) often required for ongoing investment, even though expecting demonstrable population-level impact data was likely unrealistic given the intervention’s novelty and the short pilot timeframe. The lack of robust impact data appeared to contribute directly to the closure of the Calderdale and Bridgewater pilots, yet this was not the case in Westminster. The reasons for this cannot be easily unpacked; however, the presence of senior leaders willing to invest in the service model based on a strong belief that it was the correct approach for the context, in the absence of robust population level data, was pivotal.
Implications for practice
A key lesson from this research underscores the inherent tension between the operational realities of the CHWW model and prevailing commissioning and evaluation practices. The model’s effectiveness is fundamentally rooted in building trust and strong relationships over time, allowing CHWWs to understand residents’ holistic needs and support gradual behaviour change or navigation through complex systems. Measurable impacts on population health outcomes, particularly those resulting from preventive efforts or addressing deep-seated social determinants, inevitably require a longer timeframe than typical pilot funding cycles allow. The observed short-term funding cycles and the consequent pressure to rapidly demonstrate value, leading sometimes to shifting between service models or premature closure as seen in two sites, undermine the very relational foundation of the intervention. This instability is detrimental not only to the CHWW workforce, creating job insecurity and potentially devaluing their skills, but also confuses service users and community partners, eroding the trust that is essential for the model’s success and for healthcare services more generally.
Recommendations for practice
Looking forward, acknowledging the centrality of context and the need for patience, these findings form the basis of several practical recommendations. Firstly, robust evaluation must be prioritised from the outset, moving beyond feasibility testing. This requires co-designing plans with commissioners and partners to establish agreed-upon outcomes, including realistic measures of population health impact and economic value, whilst improving data collection consistency. Secondly, primary care integration needs deliberate, clearly defined strategies. Identifying GP champions and creating structured opportunities for inter-professional learning are important for building trust, while tackling systemic barriers like IT interoperability and securing genuine PCN leadership commitment are prerequisites. Thirdly, careful workforce management is essential. Recruitment should balance local connection with role demands, and ongoing training incorporating reflective practice must be coupled with adequately resourced, dedicated, and skilled supervision providing both operational and pastoral support.
Finally, scaling requires a coordinated national approach via the NAPC-CHWW community of practice, enhancing knowledge sharing, quality assurance, and guidance on local adaptation. Future research should focus on longitudinal impact studies, qualitative exploration of user experiences, and evaluating alignment with broader policies like Integrated Neighbourhood Teams and Core20PLUS5. It should also be conducted in alignment with research occurring in other CHWW programme settings. A qualitative evaluation of a CHWW pilot programme in Cornwall [10] identified a number of facilitating and limiting factors that correspond closely to those identified here, including the primacy of experienced and supportive management teams, effective community engagement strategies that build on brand recognition and continued community presence, and strong partnerships with other community providers. Comparative studies that draw together lessons from diverse implementation settings will strengthen understanding about the CHWW model and its implementation, potentially contributing to improved efficiencies, effectiveness, and integration. For sites wishing to adopt the CHWW model, embedding these context-sensitive, evidence-informed practices, and crucially, allowing sufficient time and stable funding for them to mature, enhances the potential of the CHWW model being more sustainably realised.
Contact
Andrew Riley, University of Liverpool
andrew.riley@liverpool.ac.uk
Disclaimer
This report is independent research funded by the National Institute for Health and Care Research Applied Research Collaboration North West Coast (ARC NWC). The views expressed in this publication are those of the author(s) and not necessarily those of the National Institute for Health Research or the Department of Health and Social Care.
Acknowledgements
This research was conducted as a doctoral project by Andrew Riley at the University of Liverpool, under the supervision of Professor Nefyn Williams, Dr Matthew Harris, and Dr Clarissa Giebel. It was produced with the support and collaboration of the CHWW programme teams across the three pilot settings: NIHR ARC North West London, Westminster City Council, and Pimlico Health @ the Marven in Westminster; NHS West Yorkshire Integrated Care Board and Healthy Minds in Calderdale; and Bridgewater Community Healthcare NHS Foundation Trust in Warrington. Sincere gratitude is extended to all contributors to this study.
References
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[a] CCG = Clinical Commissioning Group; ICB = Integrated Care Board. Calderdale’s pilot was commissioned and overseen by Calderdale CCG, until 2022, when CCGs were replaced by ICBs.
