Assessing the implementation of a multi-component hypertension program in a Guatemalan under-resourced dynamic context: an application of the RE-AIM/PRISM extension for sustainability and health equity.

Background: The COVID-19 pandemic necessitated rapid changes in healthcare delivery in Guatemala's public primary care settings. A new hypertension program, implemented as part of a type 2 hybrid trial since 2019, exemplifies an implementation effort amidst a changing context in an under-resourced setting. We assessed the implementation of an evidence-based intervention (EBI; protocol-based hypertension treatment) and one of its main implementation strategies (team-based collaborative care), raising implications for health equity and sustainability. We present innovative application of systems thinking visuals.

Methods: Conducting a convergent mixed methods analysis, we assessed implementation in response to contextual changes across five Ministry of Health (MoH) districts at the pandemic's onset. Utilizing quantitative programmatic data and qualitative interviews with stakeholders (n=18; health providers, administrators, study staff), we evaluated dimensions of "Reach, Effectiveness, Adoption, Implementation and Maintenance," RE-AIM (Reach, Implementation delivery + adaptations), and "Practical Robust Implementation and Sustainability Model," PRISM (Organizational perspective on the EBI, Fit, Implementation and sustainability infrastructure) frameworks. We assessed representativeness by comparing participants to census data. To assess implementation delivery, we built behavior-over-time (BOT) graphs with quantitative programmatic data (July 2019-July 2021). To assess adaptations and contextual changes, we performed matrix-based thematic qualitative analysis. We converged quantitative implementation delivery data + qualitative adaptations data in joint displays. Finally, we analyzed qualitative and quantitative results across RE-AIM/PRISM and health districts to identify equity and sustainability considerations.

Results: Contextual factors that facilitated program delivery included the perception that the EBI was beneficial, program champions, and staff communication. Key barriers to implementation delivery included competition with other primary care activities and limited implementation infrastructure (e.g., equipment, medications). Contextual changes related to COVID-19 hindered implementation delivery, threatened sustainability, and may have exacerbated inequities. However, adaptations that were planned enhanced implementation delivery and may have supported improved equity and sustainability.

Conclusions: Recognition of an EBI's benefits and program champions are important for supporting initial uptake. The ability to plan adaptations amid rapid contextual changes has potential advantages for sustainability and equitable delivery. Systems thinking tools and mixed methods approaches may shed light on the relations between context, adaptations, and equitable and sustainable implementation.

Trial Registration: NCT03504124.