We would like to thank those whose efforts have made this report possible. Susan Hauan, from the Office of the Assistance Secretary for Planning and Evaluation (ASPE) at the U.S. Department of Health and Human Services, the project officer for the study, provided invaluable guidance throughout the course of the study, and provided very helpful comments on both the substance and presentation of material in this report. We also received valuable comments throughout the course of the study from other people at ASPE: Julia Issacs, Kelleen Kaye, and Don Oellerich. At Mathematica Policy Research, Jim Ohls and Rob Wood provided useful comments on the analysis and findings at various stages of the project. Jigar Bhatt provided outstanding programming assistance in constructing the large and complex data files and in writing the computer programs to conduct the myriad analyses that were performed for this study. Carol Razafindrakoto and Tim Novak also provided helpful programming assistance. Finally, Jennifer Chiaramonti and Bryan Gustus expertly produced the report, and Patricia Ciaccio provided valuable editorial assistance. We gratefully acknowledge these contributions.