Simulating patterns of patient engagement, treatment adherence, and viral suppression: a system dynamics approach to evaluating HIV care management.

System dynamics (SD) modeling belongs to the rapidly evolving, interdisciplinary field of system science research. This field adds value to more traditional health research by contributing to the design and testing of complex integrated models of change, to examine health system performance and patient outcomes. Using selected milestones in HIV care management to frame our simulation research, we created a SD model to examine three patient subgroups of women of color (WOC) represented in our multi-site cohort, classified by their health care seeking status at baseline. Asked to reflect on their circumstance 6 months prior to enrollment in the MSE cohort, 53% noted they were receiving some care (In Care, n = 341), 31% that they had been seeking care (Seeking Care, n = 201), and 16% that they were undecided about seeking care (i.e., answered that they may or may not look for care) for treatment of their HIV (May or May Not Seek Care, n = 103). Our SD model compared simulated patterns of patient retention over 24 months in relation to: (1) access to antiretroviral therapy (ART), (2) adherence to ART, and (3) viral suppression. Assessed patterns yielded insights about system capacities and constraints in the context of the SPNS initiative under evaluation.