Aim 1: Formative work guided by an implementation mapping process to engage key
stakeholders, finalize implementation strategies to maximize successful implementation of
the evidence-informed clinical intervention, and develop site specific adaptations of the
interventions along with an implementation blueprint to guide intervention delivery.
Proposed implementation strategies include 1) identify and prepare referral site
champions, 2) audit and feedback for referral sites, 3) build a coalition between
referral and study care sites, 4) assess for readiness and identify of implementation
barriers at care sites, 5) adaptation of intervention components to site-specific
context, 6) develop a formal implementation blueprint to guide site-specific intervention
delivery, 7) develop educational materials and conduct ongoing training at each site to
support implementation fidelity, and 8) create a learning collaborative to facilitate
cross-site sharing of best practices and positive peer pressure.
Aim 2: Following initial formative work, a type 2 hybrid implementation-effectiveness
study will be conducted using a prospective cohort of persons referred to drop-in/mobile
HIV care at one of the four participating care sites (n=400). Patients are eligible for
referral to the drop-in/mobile care model if they meet the following three criteria: 1)
most recent HIV viral load >200 copies/mL or off ART by ≥1 month by self-report; 2)
sub-optimal care engagement by self-report or chart history (defined as no current HIV
primary care provider, no HIV primary care visit in the past 6 months, or ≥ 1 missed HIV
primary care visit in the past 6 months); and 3) ≥1 major barrier to care engagement by
self report, chart history, or clinical assessment (homelessness/unstable housing, any
mental health diagnosis, any illicit substance use). The study will compare outcomes over
12 months to two propensity score-matched control groups: 1) contemporaneous patients
identified using Alameda and San Francisco Departments of Public Health (DPH) HIV
surveillance data (n=400) and 2) historical patients at participating clinic sites
(n=400). The evaluation will be guided by the RE-AIM implementation framework, with
co-primary outcomes of Reach (≥ 1 HIV primary care visit over 12 months following
referral) and Effectiveness (≥1 HIV viral load <200 copies/mL over 12 months following
referral).
In Aim 3: Impact Analysis to understand and model the individual, clinic, and
population-level impacts of the staged care approach, the study will use several
approaches: 1) Heterogeneity and Health Equity Analysis, 2) Pathway & Scenario Analysis,
3) Cost and Cost-effectiveness Analysis, and 4) Population-level Health Impact Modeling.
Analyses will use mixed-methods to assess for whom the staged care approach worked and
did not work and why. The Cost and Cost-effectiveness Analysis will estimate total
program costs, costs associated with each intervention strategy, cost per person
referred, cost per person engaged in each intervention strategy and cost per person
engaged in optimized pathways. Observed study outcomes and scenario analysis results will
be used to estimate the additional number of patients with suppressed viral load within
the entire program, for each intervention strategy and for the identified optimized
pathways.