SPACE Tool 2.0: A Downloadable Spreadsheet Tool to Measure the Impact of Sexually Transmitted Infection Program Budgets

Posted on February 22, 2024 by Erika G. Martin, PhD, MPH; Harrell W. Chesson, PhD

This entry is part 13 of 16 in the series Mar 2024

An updated, user-friendly spreadsheet tool is available to help health departments estimate the impact of changes in their STI prevention budgets.

Read the Article

Rates of sexually transmitted infections (STIs) have increased dramatically, with annual new infections contributing to $15.9 billion in lifetime medical costs. Economic analyses can assess returns on investments, facilitate resource allocation decisions, and demonstrate the value of public health services. However, health departments may not have the staff capacity or expertise to conduct economic analyses in-house. In our article, “An Interactive Modeling Tool for Projecting the Health and Direct Medical Cost Impact of Changes in the Sexually Transmitted Diseases Prevention Program Budgets,” we describe how we updated an existing spreadsheet tool to incorporate the latest scientific literature and a redesigned interface in response to user feedback.

The STI Prevention Allocation Consequences Estimator (“SPACE Tool”) model is a spreadsheet tool that estimates the impact of changes in STI prevention funding on the incidence and direct medical costs of chlamydia, gonorrhea, syphilis, and STI-attributable HIV infections. It was initially developed in 2017 by health economists and public health policy experts at the Centers for Disease Control and Prevention in response to jurisdictions’ requests for guidance on how to estimate the impact of budget changes.

What is new in the “2.0” tool?

We engaged users throughout the design process to update the interface to make it more user-friendly and engaging.
We added new functionalities requested by users, such as interactive charts that can be customized and copied into other applications such as PowerPoint.
We updated our modeling approach, which is now based on a recent scientific study that evaluated the impact of federal STI prevention funding to states on reported STI rates over a 35-year period.
We simplified the amount of information that users need to collect to customize the model to their jurisdiction.
We incorporated updated estimates for the direct medical costs of HIV and STIs.
We incorporated other scientific improvements, such as an updated approach to develop confidence intervals.
We incorporated critical model documentation, based on users’ feedback, including plain-language interpretations within the spreadsheet rather than in a separate user manual.

How can jurisdictions use findings?

SPACE Tool 2.0 is most appropriate for modeling the impact of budget changes to federally funded jurisdictions (i.e., states and directly funded large cities). It is suitable for examining small to medium relative changes in annual program funding (less than $2 per capita).

Below are some examples of past and potential future uses:

At the national level, the “1.0” model is already used regularly in annual Congressional Budget Justifications.
At the state level, the “1.0” model has been used to prepare fact sheets about the potential impact of funding changes, to illustrate the value of disease intervention specialists (DIS), and to provide summaries of program impact to government leaders.
The focus group participants interviewed in our study anticipated using findings to demonstrate the economic value of STI programs to executive leadership, provide justification for STI programs in budget proposals to state legislators, make a business case for continued investment in the disease intervention specialist workforce, and motivate internal and external audiences about the impact of STI prevention work.

How can I get the SPACE Tool 2.0 tool?

To access the downloadable tool, visit https://www.cdc.gov/std/program/space/default.htm. To learn more about the model, the underlying science, and our human-centered design process to redesign the tool, read our article, “An Interactive Modeling Tool for Projecting the Health and Direct Medical Cost Impact of Changes in the Sexually Transmitted Diseases Prevention Program Budgets.”

Additional Resources

Author Profile

Erika G. Martin, PhD, MPH; Harrell W. Chesson, PhD: Erika Martin, PhD, MPH, is a Professor of Public Administration and Policy, University at Albany. Her research focuses on infectious disease policies and programs, public health resource allocation, the adoption and impact of public health policies, public health infrastructure and data systems, and translating evidence-based research into practice.

Harrell Chesson, PhD, is an Economist at the Centers for Disease Control and Prevention’s Division of STD Prevention. His research interests include the impact and cost-effectiveness of STI prevention interventions and policies, tools to quantify the value of prevention activities, and racial and other disparities in STIs.