Mobile primary health care clinics for Indigenous populations in Australia, Canada, New Zealand and the United States: a systematic scoping review

Accessible primary health care is an inherent human right for all populations, as stipulated by the Declaration of Alma-Ata (1978) [1]. Primary health care encompasses early interventions delivered by general practitioners, nurses and allied health professionals such as health promotion, screening for disease and health education for disease prevention [1, 2]. Evidence supports the effectiveness of primary health care services in improving the management of chronic disease and addressing risk factors for developing chronic disease, across a range of contexts [3‐6]. However, primary health care services are not always accessible for all populations. This is the case for Indigenous populations in Australia, Canada, New Zealand and the United States, who often experience racism, cultural, transport and financial barriers when accessing health services [7‐10].

The multi-dimensional nature of health care access is well documented which includes the availability, accessibility, accommodation, affordability, acceptability and awareness of health care services [11, 12]. For Indigenous people, an important component of health care access is the provision of culturally safe and holistic health care by a trusted health professional who respects their values, traditions and customs [13‐15]. Across the globe, Indigenous populations are culturally and linguistically diverse, with differing environmental contexts (e.g. climates, connections to land and waterways), cultural practices (e.g. lore, customs, spiritual beliefs) and cultural identities (e.g. kinship ties, ancestors) [16]. In modern states with a history of invading Indigenous lands through the process of colonization (e.g. Australia, Canada, New Zealand and United States), there are numerous Indigenous nations, tribes and clans, all with unique cultural identities, histories and languages [16]. However, there are similarities in the experience of colonialization for Indigenous people (e.g. racism, violence, experience of European communicable diseases and loss of land), particularly in Australia, Canada, New Zealand, and the United States, which has led to enduring inequity [7, 17, 18].

To redress health inequities for Indigenous populations, including the burden of chronic disease and high mortality rate compared to non-Indigenous populations [18], culturally safe models of health care are needed which improve the accessibility of primary health care services [19]. Evidence supports that a greater participation of Indigenous people in their health care leads to better health outcomes [20, 21]. Therefore, Indigenous-governed health care services are inherent to the provision of culturally accessible health care [22]. In Australia, over 140 Aboriginal Community-Controlled Health Services (ACCHOs) provide primary health care services to Aboriginal and Torres Strait Islander people [23]. Internationally, evidence supports the important contribution of Indigenous-governed health organisations in providing culturally safe and accessible primary health care for Indigenous populations [24‐27].

Mobile clinics implemented specifically for Indigenous populations and governed by Indigenous health organisations, may be one way to improve the accessibility of culturally safe primary health care for Indigenous populations. It is known that mobile clinics are able to deliver health care to populations experiencing health inequity, particularly in countries where health care can be otherwise inaccessible due to transport, financial or cultural barriers [28‐30]. In the United States, there has been an upward surge in the implementation of mobile clinics, particularly of mobile clinics delivering primary health care services [31, 32]. The support for mobile clinics in providing flexible and safe health care to vulnerable people has gained traction with the recent COVID-19 pandemic [33]. In other countries, mobile clinics have also been implemented with the purpose of screening for communicable and non-communicable diseases [34‐36] and providing disaster relief [37, 38]. Some research supports the potential for mobile clinics to be a cost-effective model of health care and improve the management of chronic disease [29, 39].

There is also some evidence of mobile clinics being implemented specifically for Indigenous populations, either by an Indigenous health organization [40] or for a specific disease (e.g. diabetes) [41] or treatment (e.g. dialysis) [42]. What is not known, is the available evidence regarding the use of primary health care mobile clinics implemented specifically for Indigenous populations in Australia, Canada, New Zealand, and the United States who share a similar history of colonization, discrimination and barriers to accessing primary health care services [7]. This was apparent when undertaking a preliminary search of the literature for evidence around the effectiveness of mobile clinics for Indigenous populations, as part of seeking funding for a mobile clinic to be implemented in an Australian ACCHO. Indeed, it was an absence of evidence that made it difficult to obtain funding for the mobile clinic, justifying the need for a systematic scoping review. It is known that there is a vast body of literature regarding mobile clinics in the United States, yet there is very little focus on Native American, Native Hawaiian, and Alaskan Native populations [32]. A systematic scoping review was conceptualised to synthesise the available evidence regarding the use of primary health care mobile clinics implemented specifically for Indigenous populations in order to identify gaps in the literature and inform future research evaluating mobile clinics for Indigenous populations. Specifically, the review question developed was:

What is the evidence surrounding the use of mobile primary healthcare clinics implemented for Indigenous populations in Australia, Canada, New Zealand, and the United States?

Specific objectives were to: (1) scope the models of primary health care clinics for Indigenous populations (in Australia, Canada, New Zealand, and the United States) as described in the literature, (2) determine geographically where mobile primary health care clinics for Indigenous populations (in Australia, Canada, New Zealand, and the United States) have been implemented and, (3) examine the findings of any evaluations of mobile primary health care clinics for Indigenous populations (in Australia, Canada, New Zealand, and the United States) that have been published in the literature.

This systematic scoping review examines the evidence surrounding the use of mobile primary healthcare clinics implemented for Indigenous populations in Australia, Canada, New Zealand, and the United States [43]. This review was conducted in accordance with the Joanna Briggs Institute (JBI) Reviewer’s Manual 2017: Methodology for JBI Scoping Reviews [44]. Search terms were developed using a PCC (Population, Concept, Context) mnemonic. The premise and methods of this review, have been published elsewhere [43]. The Preferred Reporting Items for Systematic Reviews and Meta-analysis extension for scoping reviews checklist (PRISMA-ScR) [45] was adhered to in the reporting of this review (Additional file 1_PRISMA-ScR checklist).

Database searches yielded 1672 citations. An additional 91 citations were retrieved from an extensive search of the grey literature and targeted organisational websites. A total of 1350 unique title and abstracts were screened, after duplicates were removed. The full texts of 123 citations were screened in accordance with the review criteria, identifying 39 relevant citations (Fig. 1– PRISMA Flow Diagram). An additional 14 citations were snow-balled from 39 included citations, resulting in a total of 53 included citations discussing 25 mobile clinics.

Reasons for excluding citations were provided (Additional file 4_Excluded studies) and included: not an Indigenous-specific mobile clinic (n = 39), no mobile clinic (n = 25), not a primary health care mobile clinic (n = 12), sub-studies already included in search (n = 3), sub-studies did not meet the inclusion criteria (n = 3) and audio-recording not available (n = 2).

Information sources of citations meeting the review criteria (n = 53) included peer-reviewed journal articles (n = 18), conference presentations, papers or posters (n = 3), thesis (n = 1), independent report (n = 1), organisational annual reports or web pages (n = 25), and media releases or online news articles (n = 5).

To our knowledge, this is the first systematic scoping review examining primary health care mobile clinics implemented for Indigenous populations in Australia, Canada, New Zealand, and the United States. This review locates evidence of mobile clinics that have been implemented specifically for Indigenous populations (with the exception of New Zealand), and highlights the potential for mobile clinics to improve the accessibility of primary health care services. These findings are a valuable contribution to the growing body of international literature around the use of mobile clinics [28, 29, 32, 33, 36, 38]. Before discussing the implications of these findings, it is important to reiterate that Indigenous populations are diverse, have different languages, cultural identities, customs, lore and spiritual beliefs [16]. However, Indigenous populations in Australia, Canada, New Zealand, and the United States share the experience of colonization and require culturally safe health care embedded in the principles of self-determination [7, 16, 17, 46].

Likewise, there are key differences between the health care systems of Australia, Canada, New Zealand, and the United States, which may account for variations in the implementation of mobile clinics specifically for Indigenous populations. Australia, Canada, and New Zealand have universal access to health care for all populations [100‐102] which differs from the partially-funded health care system in the United States [103]. There are also complexities around the policies of each modern state regarding the funding of Indigenous-governed health services and programs [104]. In the United States, funding is allocated through the Indian Health Service (IHS), with a key criticism being the failure to provide sufficient resources to meet the health care needs (particularly primary health care needs) of a growing Native American, Native Alaskan, and Native Hawaiian population [17, 105]. In Australia and Canada, Indigenous health organisations (e.g. ACCHOs in Australia and on-reserve First Nations health services in Canada) receive some funding from governments to provide primary health care services to Indigenous populations, yet inequities exist in the distribution of funding (e.g. lack of funding for Métis People) and power imbalances between government and Indigenous health-organisations [17, 27, 104]. The funding structure in New Zealand differs again, with a more integrated approach of health service delivery through mainstream health services or private agencies and greater participation of Māori People in the process of informing the policy of District Health Boards (DHB) [17, 106]. The need to reform health care systems for the provision of equitable and culturally safe health care for Indigenous populations, has been widely discussed in the peer-reviewed literature [27, 104, 105].

There are also variations as to how population density is described in Australia, Canada, and the United States, which also has implications for interpreting the findings of this review (see Table 3). Australia’s Remoteness Structure [47] has a complete coverage of the continent, whereas Canada and the United States classify their urban areas by population size [48, 49]. Although there are other geographical methods for classifying population density (e.g. in Australia, Modified Monash Model [107]), this review has included classification methods used by decision-makers in each country at the time of analysis. For example, the Australian Government’s Rural Health Multidisciplinary Training (RHMT) Program [108] utilizes the Remoteness Structure [47] to guide investment to improve the recruitment and retention of health professionals in rural and remote Australia. Likewise, the Population Centre and Rural Area Classification 2016 (Canada) [48] and Urban status (United States) [49] are both based on the most recent census for each respective country and are used in government decision-making. Acknowledging these variations, this review identifies a pattern of increasing presence of mobile clinics in areas with lower population densities (see Table 3). Geographical gaps in service provision are evident (Figs. 2 and 3), indicating that the implementation of mobile clinics for Indigenous populations is not widespread.

There are also variations in the models of primary health care mobile clinics implemented for Indigenous populations. Most of the mobile clinics retrieved by this review targeted Indigenous populations across the lifespan, indicating a holistic family-centered model of primary health care, which is a preferred characteristic of Indigenous primary health care services [109]. Some mobile clinics targeted specific chronic diseases prevalent in Indigenous populations (e.g. diabetes) [110] and prevention of chronic disease for specific populations (e.g. otitis media in Aboriginal and Torres Strait Islander children) [111]. Although there was some evidence of Indigenous organisational governance or involvement in the implementation of most mobile clinics, it was difficult to ascertain the degree of Indigenous community ownership. This is a key issue which has been discussed in another review examining chronic disease programs implemented for Aboriginal and Torres Strait Islander populations [112], and in the international literature examining health services and programs for Indigenous populations [27, 113, 114]. Indigenous community ownership of mobile clinics is imperative to ensuring culture, self-determination, and community participation are embedded in the delivery of primary health care services [109].

A paucity of published and publicly available evaluations of primary health care mobile clinics implemented specifically for Indigenous populations is also highlighted. This is despite a growing body of literature evaluating mobile clinics implemented for general populations and those at-risk for developing chronic disease, particularly in the United States [28, 31‐33, 36, 39]. Although there is heterogeneity in the approaches used to evaluate mobile clinics implemented for Indigenous populations, there is some evidence that supports the potential for mobile clinics to increase attendance rates to services [54, 62, 69, 72] and improve clinical indicators (e.g. BMI, HbA1C) of targeted chronic diseases (e.g. diabetes) in Indigenous people accessing mobile clinic services [41, 79]. However, evaluation methods have relied heavily on the analysis of patient records and service data (see Table 4). The perspectives and insights of Indigenous people accessing mobile clinic services is largely absent. Findings support the need for high quality evaluations of Indigenous health programs which integrate qualitative evidence regarding the views and perspectives of Indigenous people [115]. An absence of qualitative data around the effectiveness of mobile clinics makes it difficult to know whether mobile clinics have potential to improve the cultural accessibility of primary health care services for Indigenous populations. This is a gap in existing knowledge which requires further research.

It is also difficult to examine how sustainable primary health care mobile clinics are when implemented for Indigenous populations. It is noted that the five diabetes mobile clinics retrieved from Canada were funded under the Aboriginal Diabetes Initiative (ADI), yet it is difficult to identify from the available literature as to whether all of these mobile clinics have been sustained over time under the original funding arrangement [79]. This highlights a key issue mediating the sustainability of mobile clinics in general, being the reliance on multiple funding sources (e.g. government and philanthropic) and/or short funding cycles [33]. There is also limited cost-effectiveness data around the use of mobile clinics for Indigenous populations [52]. Future research should include economic evaluations, coupled with an evaluation of the effectiveness and cultural acceptability of mobile clinics for Indigenous populations. This is imperative to informing the allocation of resources by decision-makers (e.g. governments and Indigenous-health organisations) to mobile clinics.

This review identifies geographical gaps and a paucity of evidence around the implementation of primary health care mobile clinics for Indigenous populations in Australia, Canada, New Zealand and the United States. The findings support the need to undertake rigorous mixed methods evaluations of primary health care mobile clinics implemented specifically for Indigenous populations. Through the involvement of Indigenous people in the evaluation process, greater insights will be obtained as to the potential for mobile clinics to improve access to culturally safe and holistic primary health care services. It is important for organisations implementing primary health mobile clinics for Indigenous populations, to share their experiences by making evaluations publicly available, ideally through the peer-reviewed literature. This is essential in developing evidence around innovative models of health care that have the potential to improve health outcomes for Indigenous people globally. Dissemination of evaluation evidence concerning mobile clinics will also be invaluable to decision-makers, including Indigenous health organisations, who are considering allocating resources to a primary health care mobile clinic.