Advanced models and simulations

To study the complex interactions between healthcare interventions and outcomes, PHE employs existing and custom-built models to generate credible evidence to inform decision-making.

One of PHE’s primary modeling tools is The Health Economics Medical Innovation Simulation (THEMIS), a proprietary microsimulation that tracks individuals 25 and older over their remaining lives to project future population-level health and economic outcomes. The simulation is built upon real-world patient data. Specific modules are built upon the base model in order to understand the long-term implications of interventions that treat particular diseases or policy interventions that influence pharmaceutical innovation. THEMIS was originally developed with funding from CMS, NIH, and others, from a model known as the Future Elderly Model.

PHE uses a wide range of evidence sources, including real-world retrospective databases, to build models. In some cases, multiple data sources are combined to improve model validity.

Learn more about PHE’s experience with different retrospective data sources »


  • The full technical specifications for the model with the PSID as the host dataset can be found here: THEMIS PSID.
  • The original technical specification produced by USC for the Future Adult Model can be found here: USC FAM.

Precision Medicine Group is an integrated team of experts in fields from advanced lab sciences to translational informatics and regulatory affairs, payer insights to marketing communications. Together, we help our pharmaceutical and life-sciences clients conquer product development and commercialization challenges in a rapidly evolving environment.