The cancer intervention and surveillance modeling network (CISNET) is a consortium of investigators sponsored by the National Cancer Institute "whose focus is using modeling to improve our understanding of the impact of cancer control interventions (e.g., prevention, screening treatment, etc.) on population trends in incidence and mortality" [15] . They use models to project future trends and help determine optimal cancer control strategies (for detail, see http://cisnet.cancer.gov/about/). The CISNET also describes using a comparative modeling approach in which each modeler focuses on an individual area. However, whenever possible, they develop a common "base" question that allows comparison across all models using a set of common population inputs. Then, they develop a common set of intermediate and final outputs.