Institute for Community Research
PSD Modeling to Simulate HIV Test-and-Treat Improvements

PSD Modeling to Simulate HIV Test-and-Treat Improvements

CVL Model Image

Participatory System Dynamics Modeling to Simulate HIV Test-and-Treat Improvements

This 2-year study is designed to build a computational and simulation model of the full HIV service system using a system dynamics (SD) modeling approach. We will use group model building (GMB) and multiple secondary data sources, supported by our recently funded in-depth study of the local T&T service system in Greater Hartford, CT (R01-MH103176), to build the SD computational and simulation model of that system. Using GMB, diverse community stakeholders will work with researchers to develop, validate, and test the model. The study aims are: (1) to engage a group of community stakeholders (N=20) in an iterative, participatory GMB process to develop, refine, and critique a computational SD model of Greater Hartford’s HIV T&T service system designed to simulate community viral load (CVL) over time in order to uncover system performance problems; (2) to combine GMB estimates, secondary data analysis, and relevant literature to calibrate/parameterize and formulate variables in the computational SD model and develop reference modes (epidemic trends) to validate the simulation model throughout the GMB process; (3) to demonstrate use of the SD computational model and web-based simulator app as a pilot analytical and practical tool that allows stakeholders, through simulation, to identify weaknesses and negative drivers of the system and project and compare impacts of different systems-level intervention options to reduce CVL at the city/population level. The SD computational model and simulator tool may be transferrable to other cities seeking to reduce HIV CVL with modifications using local data and stakeholder input.

Project Staff

Margaret R. Weeks, Ph.D.
Principal Investigator

Jianghong Li, MD, MSc.

Heather Mosher, Ph.D.

Marcie Berman, Ph.D.
Research Associate

Albert Einstein School of Medicine of Yeshiva University
David Lounsbury, Ph.D.

SD Modeling Task Force
Merry Bajana
St. Francis Hospital and Medical Center/Gengras Clinic
Christina Cipriani
Hartford Dispensary
Angelique Croasdale-Mills
Ryan White Greater Hartford
Ricardo Cruz
HRA of New Britain
Rocin Deutsch, MD
Brownstone Clinic
Linda Estabrook
Hartford Gay & Lesbian Health Collective
Alice Ferguson
Community Member
Nilda Fernandez
CT Children’s Medical Center (CCMC)
Seja Jackson, APRN
Burgdorf Clinic
Heidi Jenkins
CT Department of Public Health (CT DPH)
Jen Krebsbach
Gilead Sciences
Shawn Lang
Clifford Lumpkin
Community Member
John Merz
Mauricio Montezuma, MD
Community Health Services
Fernando Morales
Latino Community Services (LCS)
Tung Nguyen
Hartford Department of Health and Human Services (DHHS)
Bill Petrosky
Hartford Gay & Lesbian Health Collective
Janette Rodriguez
Community Member
Romario Roper
Community Member
Ashley Rosario
Community Member
Carol Steinke
Hartford DHHS, STI Clinic
LaToya Tyson
Yolanda Velez
LCS and Bergdorf Clinic
Danielle Warren-Diaz
SD Modeling Facilitation Team
Maryann Abbott
Marcie Berman
Natalie Garcia
Rosie Gonzalez
Danielle Green
Jianghong Li
David Lounsbury
Albert Einstein
Heather Mosher
Lucy Rohena
Margaret (Peg) Weeks


Read the Project Abstract here.


Read the project findings here.


Weeks, M.R., Green Montaque, H.D., Lounsbury, D.W., Li, J., Ferguson, A., and Warren-Dias, D. (2022) Using participatory system dynamics learning to support Ryan White Planning Council priority setting and resource allocations. Evaluation and Program Planning, 93: August:102104.

Weeks, M.R., Lounsbury, D.W., Li, J., Hirsch, G., Berman, M., Green, H.D., Rohena, L., Gonzalez, R., Montezuma-Rusca, J.M., Jackson, S. (2020). Simulating system dynamics of the HIV care continuum to achieve treatment as prevention. PLOS ONE. 2020 Mar 19;15(3):e0230568. doi: 10.1371/journal.pone.0230568. eCollection 2020. PMID: 32191771 [PubMed – in process] PMCID: PMC7082036.

Weeks, M.R., Lounsbury, D.W., Li, J., Green, H.D., Berman, M., Rohena, L., Gonzalez. R., Mosher, H.I., & Hirsch, G. System Dynamics (SD) Model of the HIV Care Continuum: Model Protocol (V.3). September 21, 2020.

Green, H.D., Weeks, M.R., Berman, M., Salvi, A., Gonzalez, R., Rohena, L., Ferguson, A., and Li, J. (2020) The impact of perceptions of community stigma on utilization of HIV care services. Journal of Racial and Ethnic Health Disparities, 7 (2): 383-391.

Green, H.D., Weeks, M.R., Berman, M., Mosher, H.I., Abbott, M., Garcia, N. Managing the risk of intimacy: accounts of disclosure and responsiveness among people with HIV and intimate partners of people with HIV. Culture, Health & Sexuality. 2018;20(10):1117-1129. PMID: 29944072;PMCID: PMC6399062.

Weeks, M.R., Li, J., Lounsbury, D., Green, H.D., Berman, M., Rohena, L., Gonzalez, R., Lang, S., Mosher, H.I. (2017). Using participatory system dynamics modeling to examine the local HIV test and treatment care continuum in order to reduce community viral load. American Journal of Community Psychology, 60 (3-4): 584-598. PMID: 29154393; PMCID: PMC5729085.