Implementation strategies and adjunctive interventions for HIV testing and linkage-to-care in the United States: a...

Ending the HIV Epidemic in the United States depends on expanding HIV testing and rapidly linking people to care. However, methods to improve testing and linkage-to-care are inconsistently described and often conflate health system-level implementation strategies with recipient-directed adjunctive interventions. We conducted a systematic review to map, classify, and synthesize these approaches and their outcomes.

We searched Ovid MEDLINE, PsycINFO, and Web of Science in 2021 and updated the search on July 26, 2023. Eligible studies were peer-reviewed, U.S.-based, and reported a real-world change method targeting HIV testing and/or linkage-to-care innovations. Two reviewers screened records and extracted data with consensus adjudication. Implementation strategies were coded to the expanded Expert Recommendations for Implementing Change (ERIC) taxonomy. Adjunctive components were coded to the Theoretical Domains Framework (TDF) and mapped to Capability, Opportunity, Motivation-Behavior (COM-B). Given heterogeneity, we synthesized narratively and, where comparators existed, coded direction of effect. This review is reported in accordance with PRISMA.

We included K = 187 studies, 151 of which report implementation strategies and 36 report adjunctive interventions. We identified a total of 756 strategies (mean ≈ 5 per study; range 1-17). Common ERIC domains included Train and Educate Stakeholders, Change Infrastructure, Support Clinicians, Adapt and Tailor to Context, and Utilize Financial Strategies. Frequently used discrete strategies were ongoing training, changing service sites, clinician reminders, audit/feedback, and revising professional roles. The most reported implementation outcome was reach (e.g., tests performed, individuals linked), captured in k = 134 (88%) strategy studies; adoption/uptake was next most common (k = 53, 35%), with far fewer reports of implementation costs, speed/efficiency, or sustainment. Adjunctive interventions predominantly targeted knowledge/skills (TDF) and reflective motivation (COM-B). Few studies explicitly addressed health equity or reported equity-stratified outcomes.

U.S. HIV testing and linkage-to-care initiatives rely on multi-component implementation strategies centered on training, workflow/site reconfiguration, and clinician-facing supports, while adjunctive interventions chiefly target recipient capability and motivation. The field would benefit from standardized outcome definitions and rigorous comparative evaluations that link discrete strategies and adjunctive interventions through hypothesized mechanisms to specific implementation outcomes, including costs and sustainment, to guide scale-up.

PROSPERO CRD42021233089.