Fig 1.
Modules comprising the system dynamics model of the HIV care continuum.
Treatment as Prevention (Module A, center); Basic Services (Modules B-E, left); Action Strategies (Modules F-I, right).
Table 1.
Modules of the HIV Care Continuum (CC) System Dynamics (SD) simulation model.
Fig 2.
Causal loop diagram: HIV treatment as prevention.
This CLD shows two reinforcing feedback structures (R1 and R2) and three balancing feedback structures (B1, B2 and B3) that collectively represent HIV burden in the community, in relation to basic services and action strategies that serve to foster access to HIV care, use of antiretroviral therapy (ART), and HIV testing. Positively associated connections (+) indicate variables that change in the same direction as each other; negatively associated connections (-) indicate variables that change in the opposite direction as each other.
Fig 3.
Stock-and-flow diagram: Population and HIV incidence (Module A, partial).
Depicts total population in the catchment area, disaggregated into ‘high’ and ‘low’ HIV prevalence communities, and the factors driving HIV infection, or incidence, over time.
Fig 4.
Stock-and-flow diagram: HIV treatment cascade (Module A, partial).
Newly infected persons transition through the treatment cascade over time, moving from being UNDIAGNOSED, to DIAGNOSED, to ENGAGED IN CARE, to achieving VIRAL SUPPRESSION.
Fig 5.
Pattern tests: Comparison of reported to simulated reference modes, 1-Jan-2017 to 1-Jul-2018 (T-12 to T6).
(a) HIV infection rate; (b) Undiagnosed HIV positive persons; (c) HIV test positive rate; and (d) HIV-specific mortality.
Fig 6.
Pattern tests: Comparison of reported to simulated reference modes, 1-Jan-2017 to 1-Jul-2018 (T-12 to T6).
(a) Engaged in care; (b) Engaged in care and virally suppressed; (c) Lost to care; and (d) Proportion virally suppressed.
Table 2.
Parameters selected for sensitivity analysis of proportion of PLWH who are virally suppressed.
Fig 7.
95% Confidence Interval about the Proportion of PLWH who are Virally Suppressed (VS) among Diagnosed PLWH. Three parameters: (1) Risky contacts per month in high prevalence areas (range: .008 –.010; base case value = .009); (2) Prop of PLWH Engaged in Care who are ADHERENT to ART (range: .85–1.0; base case value = .95); and (3) Initial Proportion of No Shows Lost to Care (range: .50 –.70; base case value = .60). Sample runs: 3 parameters x 3 values x 3 combinations = 27.