Description: This paper applies the principles and methodologies discussed in earlier papers in this series to measure cost savings from a two-year disease management DM program for the 200,000 Medicare members of a regional managed care plan. We then study how savings estimates change when we allow for four variations in key assumptions: methods for identifying or excluding plan members, requirements for eligibility in the health plan, methods for calculating health care trend and study design. Finally, we also examine the sensitivity of these results to product type by comparing the Medicare results to those of the Commercial HMO/POS product. Paper 8 of an 8 paper series titled: “Evaluating the Results of Care Management Interventions: Comparative Analysis of Different Outcomes Measures” sponsored by the Society of Actuaries’ Health Section and the Committee on Knowledge Extension Research.