Combined DES/SD model of breast cancer screening for older women, I: Natural-history simulation

<p>Two companion articles develop and exploit a simulation modeling framework to evaluate the effectiveness of breast cancer screening policies for U.S. women who are at least 65 years old. This first article examines the main components in the breast cancer screening-and-treatment process for older women; then it introduces a two-phase simulation approach to defining and modeling those components. Finally this article discusses the first-phase simulation, a natural-history model of the incidence and progression of untreated breast cancer for randomly sampled individuals from the designated population of older U.S. women. The companion article details the second-phase simulation, an integrated screening-and-treatment model that uses information about the genesis of breast cancer in the sampled individuals as generated by the natural-history model to estimate the benefits of different policies for screening the designated population and treating the women afflicted with the disease. Both simulation models are composed of interacting sub-models that represent key aspects of the incidence, progression, screening, treatment, survival, and cost of breast cancer in the population of older U.S. women as well as the overall structure of the system for detecting and treating the disease.