Measuring success: the case for calculating the return on investment of environmental public health tracking.

The Centers for Disease Control and Prevention's Environmental Public Health Tracking (EPHT) Program has funded multiple partners to develop a nationwide surveillance system that focuses on the environment and its impact on human health. To show that investing in a nationwide EPHT Network is a sound practice, the program must demonstrate that monetized improvements to the public's health due to tracking outweigh the costs. In the process of developing capacity for the EPHT Network, programs have had a positive impact on the public health. Results from successful programs can be used to estimate financial measures of the EPHT performance, such as net present value, return on investment, and payback period. The estimation of such measures for the EPHT requires an understanding of the economic elements for analysis in the context of surveillance systems. A quantitative assessment must take into account elements that are difficult to measure and value. By performing a return on investment, a financial measure of program performance, the expected costs and potential benefits of individual projects need to be assessed and compared with the current cost burden of the health condition.