Implementation Science for HIV Prevention and Treatment in Indigenous Communities: a Systematic Review and Commentary

Purpose of Review We systematically reviewed implementation research conducted in Indigenous communities in the Americas and the Pacific that focused on improving delivery of HIV preventive or treatment services. We highlight strengths and opportunities in the literature and outline principles for Indigenous-led, HIV-related implementation science. Recent Findings We identified 31 studies, revealing a consistent emphasis on cultural tailoring of services to Indigenous communities. Common barriers to implementation included stigma, geographic limitations, confidentiality concerns, language barriers, and mistrust. Community involvement in intervention development and delivery emerged as a key facilitator, and nearly half of the studies used community-based participatory research methods. While behavioral HIV prevention, especially among Indigenous youth, was a major focus, there was limited research on biomedical HIV prevention and treatment. No randomized implementation trials were identified. Summary The findings underscore the importance of community engagement, the need for interventions developed within Indigenous communities rather than merely adapted, and the value of addressing the social determinants of implementation success. Aligned to these principles, an indigenized implementation science could enhance the acceptability and reach of critical HIV preventive and treatment services in Indigenous communities while also honoring their knowledge, wisdom, and strength. Supplementary Information The online version contains supplementary material available at 10.1007/s11904-024-00706-z.


Introduction
HIV remains a significant public health challenge in Indigenous communities across the Americas and the Pacific.Reported rates of HIV diagnosis are disproportionately high for Indigenous peoples in Australia, Canada, Aotearoa/New Zealand, and the United States (US) [1].In the U.S., between 2017 and 2021, annual HIV diagnoses among American Indian/Alaska Native (AI/AN) people increased by 16% and diagnoses among Native Hawaiians and other Pacific Islanders increased 55%; diagnoses decreased for all other racial and ethnic groups [2].AI/AN people also have the shortest survival time after diagnosis among racial and ethnic groups in the US, reflecting inequities in access to testing and treatment uptake [3].HIV prevalence in Indigenous communities in Venezuela (Warao), Peru (Chayahuita), and Colombia (Wayuu women) has been estimated at 9.6%, 7.5%, and 7.0%, respectively, substantially higher than the general population average of 0.4% in the region [4,5].Papua New Guinea has the highest incidence and prevalence of HIV in the Pacific, and infection rates there are steadily increasing [6].Multiple factors contribute to these inequities, including differential exposure to the social determinants of health, with Indigenous communities often facing higher rates of poverty and unemployment than non-Indigenous communities [7,8].Limited access to healthcare -often exacerbated by remote living conditions, a lack of culturally safe services, and chronic under-funding in violation of treaty agreements -further hinders effective HIV prevention and treatment [9,10].Furthermore, the effects of colonization, coloniality, racism, and discrimination, which have disrupted traditional social structures and introduced new vulnerabilities, play a significant role in the current HIV epidemic in these populations [8,11].Addressing these challenges requires a multifaceted approach that respects and integrates Indigenous knowledge, values, and systems [12].
As noted in the literature, inequities in the implementation of health interventions for different population groups contribute to differential health benefits [13].Thus, implementation science, which focuses on understanding and addressing barriers to the effective adoption of evidence-based interventions, has the potential to help to bridge these gaps.As a relatively new, rapidly growing field using a range of interdisciplinary methods, implementation science is unique in its focus on the 'how' of health service delivery in the real world [14].Core to the science are implementation strategies -deliberate approaches to facilitate intervention delivery, including training, financial incentives, and audit and feedback [15,16].Implementation science measures the outcomes of these strategies, focusing on concepts like acceptability, feasibility, fidelity, and sustainability [17].Implementation science with a health equity focus could thus offer insights into appropriate strategies for implementing HIV prevention and treatment services in Indigenous communities, including the tailoring of culturally safe services.to align with local priorities, practices, and knowledges, thereby leveraging their known strengths [10].
Given the urgent need to improve HIV outcomes in Indigenous communities and the potential of implementation science to support this goal, we sought to understand the scope of current research in this area.Our objectives were to review implementation research conducted in and with Indigenous communities in the Americas and the Pacific that focused on improving delivery of HIV prevention or treatment services, with the intent of outlining principles for future Indigenousled, HIV-related implementation science.

Search Strategy
We searched PubMed on June 29, 2023 to identify original peer-reviewed research in any language that 1) evaluated the implementation of HIV preventive or treatment interventions, 2) assessed at least one implementation outcome as specified by Proctor et al. (2011) or Glasgow et al. (1999) [17,18], and 3) enrolled from a majority Indigenous population in North America, Central America, South America, or the Pacific (i.e., Australia, Aotearoa/New Zealand, Polynesia, Micronesia, and Melanesia).The full search strategy is presented in Additional File 1.

Study Selection
During the title and abstract screening phase, all database results were uploaded into ASReview, an active learning tool designed to assist systematic review screening by automatically categorizing results by relevance [19].Prior research has shown that ASReview's algorithm can identify 95% of the final selected publications within the initial 20% of the publications shown, significantly reducing the time required for screening while ensuring the quality and integrity of the results [20].The first author (CK) manually reviewed all results using ASReview.Studies were included at the title and abstract screening phase if they appeared to be related to HIV/AIDS in Indigenous communities.We then used Covidence for full-text screening [21].A mix of two authors (CK, AE, GK, or LW) independently screened all full-text articles and noted reasons for exclusion.Studies passed the full-text screening stage if they met all inclusion criteria.Discrepancies in eligibility assessments were resolved through discussion until consensus was reached.

Data Abstraction
Two authors (CK and AE) independently piloted a structured abstraction form on Covidence.One of four authors (CK, AE, GK, or LW) then abstracted study, intervention, and implementation strategy characteristics for the remaining studies, while another author independently verified each abstraction, and then resolved any disagreement through discussion.We abstracted study settings, objectives, study design and methods, whether community-based participatory methods were used, whether any author-identified Indigenous research methods were used, study populations, HIV prevention or treatment interventions of focus, types of implementation strategies used [22] -including author-defined Indigenous implementation strategies, implementation outcomes reported [17,18], HIV-related outcomes reported, and conclusions or lessons learned.Risk of bias was not assessed as no metaanalysis of effectiveness was conducted.

Analysis
Percentages were calculated for all categorical variables; these were used to summarize study characteristics.Quantitative meta-analysis of study findings was not possible given the heterogeneity in research questions and outcomes.

Results
Our search yielded 484 articles.We excluded 435 during title/abstract screening, leaving 49 for full-text review.Of these, eight were excluded for not assessing implementation of an HIV treatment or preventive intervention, six were excluded because they did not plan to measure or report an implementation outcome, three were excluded because they were not conducted in or with an Indigenous community, and one was excluded for multiple reasons (Fig. 1).
The final sample included 31 studies (Table 1) .Table 2 provides descriptive statistics.The largest number (10, 32.3%) were conducted in Canada, followed by the United States (9, 29.0%) and Australia (4, 12.9%).Two (6.5%) were study protocols; the rest presented empirical data.A range of formative and evaluative study designs were adopted; cross-sectional qualitative or survey designs (9, 29.0%) and quasi-experimental designs, including prepost without control designs (8, 25.8%), were the most used.Nearly half (15, 49.4%) of studies used key-informant interviews.Community-based participatory research methods  were clearly specified in fifteen (48.4%) studies.Indigenous research methods used included gathering or talking circles and the Aboriginal ownership, control, access, and possession (OCAP) model [54].Most studies evaluated implementation of behavioral HIV prevention programs (17, 54.8%), and twelve (38.7%) evaluated implementation of testing programs.
We organize our summary of HIV-related implementation research in Indigenous communities by the prevention or treatment interventions of focus in each study.Studies evaluating implementation of multiple interventions are categorized by the most upstream intervention (i.e., testing, then behavioral prevention, then biomedical prevention, then treatment, then other interventions).

HIV Testing
Three studies explored the perspectives of different Indigenous communities on HIV testing.Bucharski et al. (2006) conducted a study with Canadian Aboriginal women, noting several barriers to testing uptake but also identifying guiding principles for culturally appropriate testing programs [28].Palma-Pinedo and Reyes-Vega (2018) conducted a similar study in the Peruvian Amazon and found barriers including geographic limitations, sociocultural challenges, confidentiality concerns, language barriers, mistrust of the screening process, and limited healthcare resources [42].They also emphasized the need for culturally sensitive and differentiated care.Finally, Sianturi et al. (2022) conducted a study in Indonesia to understand the reasons for the lack of acceptance of HIV programs among Indigenous Papuans.They argued for community-based, multi-sectoral, culturally sensitive approaches to educating and building awareness around HIV [52].
Five studies assessed the acceptability, feasibility, and uptake of specific testing approaches.Miller and Torzillo (1998) evaluated the uptake of HIV testing in remote Aboriginal communities in Australia, crediting the high uptake among high-risk groups to the confidentiality that was maintained and to the use of community-wide education [25].Three studies were related and conducted with Indigenous communities in the Brazilian Amazon.Benzaken et al. (2014) demonstrated the feasibility of dried tube specimens (DTS) for external quality assurance of point-of-care syphilis and HIV testing [35].Ruffinen et al. (2015) assessed the implementation of a point-of-care screening program for syphilis and HIV in these communities, describing the context for the introduction of the testing, evaluating the performance of the healthcare system, and describing barriers to and facilitators of implementation success.Their results formed the basis for the design of strategies to improve the feasibility, viability, and sustainability of introducing  2022) explored the acceptability of dried blood spot testing (DBST) for HIV, STIs, and blood-borne infections among Métis people in Alberta, Canada.They used a mixed-methods approach, including gathering circles, and found that DBST was highly acceptable to Métis community members and could be part of a culturally grounded, Métis-specific epidemic response [50].
Two studies evaluated more comprehensive testing related intervention packages.Treloar et al. (2018) assessed the acceptability of the Deadly Liver Mob program, which was aimed at engaging Aboriginal Australians in hepatitis C and sexual health education, screening, and care, including educational sessions about HIV and referral to a sexual health service for HIV assessment and screening.They found that the program was acceptable to staff and clients and was effective in increasing the proportion of Aboriginal clients attending health education and screening services [43].Tu et al. (2013) discussed the implementation of the chronic care model (CCM) to improve HIV care in a predominantly Indigenous population in Canada.The CCM includes enhancing clinical teamwork, promoting evidence-based clinical recommendations, empowering patients to manage their own care, and creating a framework for population-based quality improvement initiatives.The authors found that the CCM led to improvements in HIV implementation outcomes, including increased rates of testing, treatment uptake, and effectiveness outcomes, such as viral suppression [34].

Behavioral Prevention
Behavioral HIV prevention with Indigenous youth was a major focus; most of these studies used community-based, culture-forward approaches, and authors emphasized the importance of community involvement and cultural relevance in successful program adoption, implementation, and maintenance.Baldwin et al. (1996) documented the collaborative development and implementation of culturally sensitive HIV/AIDS and substance abuse prevention curricula for Native American youth, demonstrating the adaptability of multi-component preventive intervention curricula for Native American communities when combined with formative research activities and community input [24].Aguilera and Plasencia (2005) described programs hosted by the Native American Health Center's Youth Services that incorporate traditional cultural activities and empowerment to reduce risk.The authors emphasized the importance of community healing, healthy traditions, and family involvement [26].Mikhailovich and Arabena (2005) reported on the Indigenous Peer Education Project (IPEP), which trained young Indigenous Australians to become sexual health peer educators, finding positive effects on participants' knowledge and skills in sexual health education [27].Lowe (2008) used a measure of Cherokee self-reliance and conducted a feasibility study using talking circles -a traditional coming-together approach -to deliver HIV/AIDS and HCV prevention material to Native American adolescents [31].
Four of these studies were related.Craig Rushing and Stephens (2012) first described the work of Project Red Talon -a STD/HIV prevention project with the Northwest Portland Area Indian Health Board Tribal Epidemiology Center -and their use of community-based participatory research methods to review existing technology-based interventions and generate recommendations for designing culturally appropriate media-based interventions for Native youth [32].Craig Rushing and Gardner (2016) then described the adaptation process for a video-based HIV/STI intervention (Native VOICES) using the ADAPT-ITT model, including the development of a culturally tailored intervention toolkit [38,57].Shegog et al. ( 2017) also described the adaptation process of the Native It's Your Game curriculum, which included a needs assessment and the development of a web-based curriculum incorporating Native culture and language, all informed by cultural sensitivity adaptation frameworks and principles [40,58].Finally, Markham et al. (2022) detailed the development of the Healthy Native Youth Implementation Toolbox, which is a decision support system for implementing culturally-relevant sexual health education programs, adapted from the iCHAMPSS (CHoosing And Maintaining Effective Programs for Sex Education in Schools) toolkit using the process of implementation mapping [51,59].
As part of a separate effort, Lee et al. ( 2018) described the adaptation of an HIV prevention intervention (Becoming a Responsible Teen, BART) for Native American adolescents.The authors received input from an advisory board, modified the intervention to be more consistent with Native American culture, and conducted a pilot study, finding that the adapted intervention was highly acceptable [41].Kaufman et al. (2021) conducted a national survey of stakeholders involved in sexual health programs for Native American youth and sought to understand the factors that might facilitate or hinder their use of a particular evidence-based risk reduction intervention.They found that perceived trialability, compatibility, and observability all influenced the likelihood of intervention uptake [47].
In the oldest study in our sample, Crown et al. (1993) documented the challenges faced by Canada's Northwest Territories in implementing HIV prevention strategies, including language barriers, cultural taboos, and confidentiality concerns, noting that programs were facilitated by the involvement of community members and the efforts of Community Health Representatives [23].Worthington et al. (2020) also conducted a qualitative study on rural and remote regions community-based HIV/ AIDS prevention interventions in Canada, highlighting the importance of involving communities in program development, building relationships and partnerships, assessing community readiness, program flexibility, and addressing stigma [46].
In the most recent study in our sample, Nogueira et al. (2023) aimed to culturally adapt an evidence-based HIV intervention for traditional birth attendants (comadronas) in rural Guatemala.The study found that the adapted intervention was acceptable, suitable, and feasible for the comadronas, and increased their confidence in HIV prevention [53].

Biomedical Prevention
Two studies focused only on biomedical HIV prevention.Newman et al. (2012) examined the acceptability of a vaccine for HIV among sexually diverse Aboriginal peoples in Canada, identifying barriers to acceptance including mistrust, concerns about safety and efficacy, stigma, and cost.They emphasize the need for culturally appropriate dissemination approaches, including community engagement and working with local leaders [33].Ansari et al. (2017) conducted a study in Papua, Indonesia to assess the acceptability and feasibility of voluntary medical male circumcision (VMMC), finding initially that demand was weak due to lack of prior socialization and concerns about safety and religious appropriateness [39].

Treatment
Two studies focused on HIV treatment.Ubrihien et al.
(2021) described a study protocol aiming to improve STI treatment outcomes for Aboriginal young Australians by addressing barriers to accessing sexual health services [48].Gabster et al. (2022) similarly used interviews to assess the barriers and facilitators to treatment adherence and retention in HIV care among the Indigenous population in the Ngäbe-Buglé Comarca, Panama.Identified barriers included psychological health, family and community support or discrimination, and difficulties in accessing ART care due to travel costs, ART shortages, and challenges in navigating between Western and Traditional medical systems.One of their recommendations was to foster formal collaboration between Western and Traditional providers [49].

Other
Four studies were concerned with HIV services generally.Two were from Australia.Andersson et al. (2008) outlined the protocol for the Aboriginal Community Resilience to AIDS (ARCA) research project, which aimed to investigate the role of resilience in the health and well-being of Canadian Aboriginal youth in relation to STIs and blood-borne viruses, using both talking circles and the OCAP model [29].Barlow et al. (2008) further explored the issue of culturally competent service provision for Aboriginal people living with HIV/AIDS in Canada, again using the OCAP model.They also highlighted the importance of treating addictions and HIV/AIDS together [30].
Two studies in Canada related to identifying community needs and resources.Larcombe et al. ( 2019) described a pilot project by the Dene First Nations community in northern Manitoba, using both the community readiness model and OCAP model to develop culturally appropriate HIVrelated interventions and programs [44].Jongbloed et al.
(2020) conducted a study of mobile phone ownership and usage among young Indigenous people in British Columbia who have used drugs with the goal of understanding challenges and potential solutions for engaging them in mobile health programs related to HIV and other conditions [45].

Discussion
We identified 31 implementation research studies related to HIV prevention or treatment services in Indigenous communities in the Americas and the Pacific.Studies consistently emphasized the value of culturally safe services that are appropriately tailored to meet the needs and work in tandem with the strengths of Indigenous communities.Geographic limitations, confidentiality concerns, language barriers, mistrust, and insufficient healthcare resources were commonly identified barriers to implementation.Community involvement in intervention development, adaptation, and delivery was consistently noted as a key implementation facilitator, and around half of the studies used community-based participatory research methods.The largest number of studies were focused on behavioral HIV prevention, particularly among Indigenous youth, again using community-based, culture-forward approaches.Relatively few studies were focused on biomedical HIV prevention, with none evaluating programs seeking to improve access to or uptake of Pre-Exposure Prophylaxis (PrEP), and few related to HIV treatment.No randomized implementation trials were identified.
Our results highlight the growing role of implementation research in supporting HIV services for Indigenous communities.Studies used a diverse range of implementation research methods and strategies, uniquely incorporating several Indigenous approaches, including talking circles, for both data collection and intervention delivery.The absence of randomized trials in our sample is consistent with the observation that such trials may be considered culturally inappropriate in some Indigenous communities [60].Studies predominantly focused on early-stage implementation outcomes such as patient-and provider-level acceptability and feasibility, finding that confidentiality, community education, and cultural adaptation improved intervention user perceptions of satisfaction and fit.However, in alignment with most other implementation research, few studies measured later-stage implementation outcomes like fidelity, cost, or sustainability [61][62][63][64].Maintaining fidelity is vital to ensuring interventions work as intended [65].Because a substantial number of HIV implementation studies include community-engaged methodologies, added attention to fidelity may inform our understanding of how implementation practitioners can hold the tension between community implementation and fidelity in Indigenous communities (e.g., Fidelity-Adaptation Dilemma [66]).Demonstrating cost, cost-effectiveness, and sustainability is crucial for justifying expansion, especially with constrained resources [67].For example, healthcare for Indigenous communities in North America is drastically under-funded: the per capita Indian Health Service (IHS) funding allocation is approximately one third of US per person health care spending and 40% of per person federal inmate spending [68].Thus, cost is a vital consideration for IHS, tribal governments, and tribally owned health systems when planning for implementation of health services in AI/AN communities.
We further situate this review within ongoing efforts to critique and strengthen the field of implementation science by elevating the insights and epistemologies of marginalized and under-represented communities, including those of Indigenous communities, and by rejecting oppressive or exclusionary forms of knowledge production [69,70].For example, noting that implementation science inadequately addresses systemic disparities designed to maintain racial inequalities, Bradley et al. draw on critical race theory and the Black radical tradition to help the field "center at the margins" to more effectively dismantle these systems of oppression that hinder access to health services [71].Comparable reviews of implementation research applied to other types of health services in Indigenous communities have similarly noted that centering Indigenous epistemologies, using Indigenous research methodologies, building in extensive community participation, and paying attention to cultural safety will all help to mitigate epistemic injustice and improve the science [72,73].Such work has clear practical benefits: for example, the successful implementation of COVID-19 vaccination in Indigenous communities -with vaccine uptake rates in the US that were the highest among US race and ethnic groups -has been attributed to the centering of Indigenous practices and principles within those efforts [74,75].Even when applied to non-Indigenous or non-marginalized communities, implementation science would likely benefit from these epistemologies and practices.For example, implementation sustainability research could grow by integrating the Indigenous principles of Seventh Generation philosophy, or the idea that we should move through the world while keeping in mind the next seven generations of Earth's inhabitants [76].
To maximize the potential benefit of future HIV implementation science for Indigenous communities, we argue that studies should be anchored to several guiding principles.First, respect for Indigenous sovereignty must be paramount.Interventions, implementation strategies, and implementation studies must be developed in meaningful partnership -recognizing and acknowledging the multiple forms of Indigenous knowing, being, and doing inherent within Indigenous communities.Such implementation work benefits from the science and wisdom held within Indigenous communities and has potential to expand intervention reach via cultural and contextual relevance.Second, while cultural adaptation of existing interventions is valuable, there is a need for the development and evaluation of interventions by, with, and for Indigenous communities.This challenges the prevailing 'top-down' paradigm in implementation science, which often presumes the desirability of interventions that have been evaluated elsewhere.Often, such 'evidence-based' interventions are tested under highly controlled (i.e., RCT) study designs in well-resourced academic settings, including mostly WEIRD (white, educated, industrialized, rich, democratic [77]) participant samples.Lack of attention to the differences in development versus implementation contexts may limit generalizability and contribute to implementation failure in marginalized communities [78].The systematic failure of implementation in marginalized contexts contributes to the inverse-prevention law, in which those who most need evidence-based interventions are the least likely to receive them.Rather than an overreliance on adaptation, which can often take the form of changing only surface elements of interventions to fit Indigenous communities (i.e., "tagging a feather on it" [79]), a more equitable approach is to build interventions in contexts with the least, rather than the most, resources [80].Using participatory approaches to develop and evaluate HIV preventative and treatment interventions in partnership with Indigenous communities has a dual promise of addressing the inverse-prevention law and expanding reach via cultural alignment and responsiveness.Third, given ongoing resource constraints and deep mistrust in many Indigenous communities of health systems and policymakers [81], we argue that future implementation studies must consider higher-level barriers to implementation, or what we might call the social determinants of implementation success [82].We hypothesize that HIV implementation studies that strive to understand and counteract the effects of historical and inter-generational trauma, alongside the impacts of multiple intersecting systems of oppression on Indigenous communities, will expand the uptake and reach of HIV preventative and treatment programs.Fourthly, a strengths-based approach should be adopted, identifying and leveraging the unique resources, resilience, and implementation facilitators inherent in Indigenous communities.This shifts the narrative from one of deficit to one of empowerment [83].Fifth, the use of Indigenous research methods and implementation strategies should be prioritized, ensuring that the research process itself is culturally congruent and respectful, and builds from effective practices of healing and doing that are already present within Indigenous communities.Sixth, there is an urgent need for implementation scientists to build capacity for implementation research within Indigenous communities.Lastly, HIV implementation studies must respect and reflect diversity both within and across Indigenous communities.These communities are not monolithic; all have distinct histories, epistemologies, and practices.
Several limitations to our review approach should be noted.First, our search was confined to PubMed, potentially excluding relevant studies indexed in other databases.Second, we restricted our search to Indigenous communities in the Americas and the Pacific, excluding research conducted with numerous Indigenous and colonized communities around the world.Third, though we highlighted the role of community engagement in each study, our review did not systematically assess the depth or quality of such engagement.Future work should be done to assess the quality and depth of academic-community partnerships to understand the processes of community engagement that are linked with improved implementation outcomes.Finally, given the dynamic nature of implementation science and the rapidly evolving landscape of HIV prevention and treatment, our exclusive use of peer-reviewed, published studies may mean we have missed recent developments and ongoing studies.

Conclusions
Despite these limitations, our review offers a foundation upon which HIV implementation research in Indigenous communities can build.Future studies must expand the scope of this research, particularly to address high-priority HIV prevention and treatment services like PrEP and long-acting injectable treatment, to consider higher-level determinants of implementation success, and to rigorously assess later-stage implementation outcomes including cost and sustainability.They could identify culturally safe strategies for expanding access to and uptake of PrEP in Indigenous communities, explore the role of traditional healers and people with lived experience in these strategies, point to the most effective policy-level strategies for ensuring governments and health systems meet treaty obligations and respect Indigenous sovereignty, and identify the implementation strategies that are most congruent with community engagement and most effective at healing the effects of historical and intergenerational trauma.Our study also underscores the potential for an Indigenous implementation science that is culturally safe, community-based, and participatory.Evidence source matters -interventions and implementation strategies that are developed and evaluated by, with, and for Indigenous communities, and that are grounded in Indigenous ways of knowing, being, and doing, are likely to be more successful than those imported and adapted from other settings.We argue for a strengths-based approach that builds from the healing power of Indigenous traditions while acknowledging the realities of historical and intergenerational trauma, racism, oppression, the chronic and systemic under-funding of healthcare, and broken treaty obligations.Relational implementation strategies could leverage strong ties and social networks in Indigenous communities [84].An Indigenous implementation science could enhance the acceptability, reach and effectiveness of critical HIV preventive and treatment services in Indigenous communities while also honoring their self-determination, knowledge, wisdom, and strength.