Meet the team that is guiding us forward.
The Lewin Group cultivates world-class leadership. This shines through in the relationships we keep and the quality insights we develop.
Lewin has built one of the most successful research
and policy analysis firms in the country.
Meet the Lewin Leadership Team
Chief Executive Officer
Michael Nestor joined The Lewin Group in 2013 and is the chief executive officer of the organization. In this role, Nestor provides end-to-end leadership across all aspects of The Lewin Group.
A successful executive with more than 20 years’ experience, Nestor has developed corporate business strategies and complex enterprise initiatives to deliver innovative solutions to enhance customer satisfaction, drive revenue growth and reduce operational expenses.
Prior to joining Lewin, Nestor served in multiple executive roles as part of the rescue team for the initial roll out of Healthcare.gov among others.
Nestor received his bachelor’s degree in management information systems from New York University and is a recipient of the NYU Founders Day Award for academic achievement.
Sr. Vice President, Center of Aging & Disability Policy
Lisa Alecxih is a nationally recognized expert in long-term services and supports financing and service delivery.
She has extensive research experience with systems change related to supportive services for older adults and individuals with disabilities and the intersection of health and social services for these vulnerable populations.
Alecxih helps governments transform their long-term support systems to be consumer-focused and cost-effective. Greater integration of long-term services and supports into the health system to better support vulnerable populations is an important focus for her work.
She received a master's of public administration in public affairs from the Lyndon B. Johnson School of Public Affairs at the University of Texas.
Charlie Bruetman, MD
Sr. Vice President, Federal Health & Human Services
As the leader of Lewin’s Federal Health and Human Services market, Dr. Charlie Bruetman is responsible for developing the team’s strategy, growth, opportunity assessments and ensuring appropriate resources to deliver high-quality products to the organization’s clients.
Dr. Bruetman has extensive experience providing policy analysis, program evaluation and support, and developing clinical quality measures across U.S. federal health care agencies, including transformation engagements at CMS.
He received his MD degree from the University of Buenos Aires, Argentina, and his master’s degree in business administration from the Kellogg Graduate School of Management at Northwestern University.
Sr. Vice President, Comparative Effectiveness Research
Cliff Goodman has 30 years of experience working with government, industry, and nonprofit organizations in such areas as health technology assessment, comparative effectiveness research, health economics and health care innovation.
A compelling public speaker, Goodman is a nationally recognized health issues moderator and panel facilitator. He is past president of the Health Technology Assessment International, and is a Fellow of the American Institute for Medical and Biological Engineering.
He received a Doctor of Philosophy from The Wharton School, University of Pennsylvania, a Master of Science from The Georgia Institute of Technology, and a Bachelor of Arts from Cornell University.
Sr. Vice President, Security & Emergency Preparedness
A member of The Lewin Group for 30 years, Paul Hogan applies microeconomics, econometrics, cost/benefit analyses, statistics and research methods to problems of health economics, labor supply, compensation, training, performance and cost measurement.
Hogan’s areas of research in health economics include workforce studies and measures of Medicare and Medicaid payment accuracy.
His doctoral studies include economics, econometrics and finance at the University of Rochester. He completed his undergraduate work in economics at the University of Virginia.
Sr. Vice President, Business Development, States
Yvonne Powell offers broad insights across the continuum of health care services, including managed care program design, acute care and long-term care financial modeling, and the design of long-term care and community support services for populations with special needs.
Powell has more than 20 years’ experience in public sector delivery of health care services, providing policy, programmatic and technical assistance to state Medicaid programs. This includes evaluating and designing new health care delivery structures and methods.
Powell received a master's degree in public policy from the University of Michigan.
Carol J. Simon, PhD
Sr. Vice President, Evaluation and Advanced Analytics
Carol J. Simon, PhD, leads The Lewin Group’s Center for Evaluation and Advanced Analytics. She brings more than 25 years of experience in health economics, evaluation design and policy consulting to help government clients design and implement effective health reforms.
Author of more than 40 peer-reviewed articles, Simon’s work has appeared in the American Economic Review, Journal of Health Economics and Health Affairs, and has been cited in the New York Times, Wall Street Journal and health care business publications.
She was an associate professor and director of the health economics program at Boston University, and a professor of public policy at the University of Illinois, University of Chicago, and UCLA; she has a doctorate from the University of Chicago and a master’s from MIT.
Erika Ange focuses on developing and refining policies and processes for Lewin. She uses her consulting, business development and strategy background in areas such as quality management system/ISO processes, recruiting, resource management and project management.
She has managed complex projects involving multiple stakeholders, including working with state, federal and private clients on Medicaid, focusing on the design, implementation and evaluation of managed care programs, program integrity and special populations.
Ange received her bachelor of science in human development from Cornell University and her master's in health care administration from the University of North Carolina-Chapel Hill.
Karen F. Davenport, MPA
Karen Davenport’s 25-year career includes health care financing and women’s health care policy. Her work has shaped policy and program development in health coverage, long-term services and supports, and payment and delivery system reform.
Davenport previously served as director of health policy for the National Women’s Law Center in Washington, D.C., where she directed research and advocacy programs. She convened the Women in Health Care Coalition to coordinate women’s health advocacy efforts.
Davenport’s previous positions include research project director and lecturer at George Washington University, and Washington director at the Medicare Rights Center. She is a graduate of Whitman College and has a master’s degree from Syracuse University.
Laura A. Dummit
Dummit brings more than 25 years of policy analysis experience, focused on payment policies, and health care markets and spending, including a multi-year project for the Centers for Medicare & Medicaid Services on coordinating care for Medicare-Medicaid enrollees.
She has led engagements on Medicare Special Needs Plans, accountable care organizations, Medicaid health plans, and home- and community-based services. She was formerly the director for Medicare payment issues at the U.S. Government Accountability Office (GAO).
Dummit has also held positions with the Alpha Center for Health Planning, the National Health Policy Forum and the Office of the Assistant Secretary for Planning and Evaluation in the U.S. Department of Health and Human Services.
Cindy Gruman, PhD
For nearly 30 years, Cindy Gruman, PhD has worked to improve the quality of life for individuals connected to the health and human services system by conducting policy studies, literature reviews, gap analyses and employing innovative knowledge-sharing methods.
Gruman has managed projects or collaborated on projects for the Administration for Children and Families, Veteran’s Administration, the Health Resources and Services Administration, Centers for Disease Control and Centers for Medicare and Medicaid Services.
Findings from her research have been published in peer-reviewed scientific literature, presented at national meetings and disseminated to federal and state policymakers. In addition, she has co-written many detailed legislative, public policy and health policy reports.
Steve Johnson has over 33 years of experience working with Medicaid claims data and conducting financial analyses of Medicaid program issues. A risk adjustment expert, Johnson has helped several states implement risk adjustment payment systems.
He is the principal author of the CMS manual “Implementing a Risk Adjusted Payment System for State Medicaid Programs,” and is an expert at processing large health care claims data sets.
He has directed numerous projects profiling the quality and quantity of data submitted by managed care plans and network providers. Johnson received his PhD in Economics from the State University of New York at Albany.
Jennifer Kuo has more than 10 years of experience in project management, program evaluation and assessment, technical assistance, qualitative and quantitative data collection and analysis, evaluation design and planning and performance measurement.
She has directed numerous large-scale projects for Federal health agencies, including AHRQ, HRSA and CMS, and for private-sector clients on topics including quality improvement, evidence-based medicine, organ transplants, maternal and child health and mental health.
Kuo received her bachelor’s degree from Rice University and her Master of Health Sciences in health policy from The Johns Hopkins Bloomberg School of Public Health.
Grecia M. Marrufo has extensive experience conducting empirical research on a wide range of health care programs, including managing projects and applying econometrics methods to assess policy impacts on access to care, expenditure and utilization rates.
Marrufo was a principal research director at Acumen LLC where she focused on the Medicare program, including evaluation studies on payment demonstrations and program interventions, models to simulate the impact of changes in coverage, and performance measurement.
She received a Doctor of Philosophy in Economics from the University of Chicago.
Elizabeth Martin joined Lewin in 2015 after a successful tenure as vice president of Program and Network Integrity for Optum® Specialty Networks. In that role, Martin participated in health care initiatives that served members in the private and public sectors.
Overseeing system change and program realignment, Martin directed all public and commercial fraud, waste, and abuse efforts for behavioral and physical health programs, with a focus on community-based programs to improve the lives of those with complex needs.
An expert in alternative financing and program infrastructure, Martin received her law degree from Boston College and a business degree from Creighton University. Martin is also a candidate for an MA/PhD in depth psychology at the Pacifica Graduate Institute.
Traci Padgett, MPP
Traci Padgett serves as a vice president in Lewin’s Federal Health and Human Services practice. She has more than 20 years of experience in health care analytics, home- and community-based care, standards development, quality measurement and performance improvement.
She is a lead for the State Innovation Model (SIM) All-Payer Operations contract. Padgett formerly served as executive vice president at the Community Health Accreditation Partner (CHAP), a national accreditor of home and community-based care.
She has a master’s degree in public policy from the John F. Kennedy School of Government at Harvard University.
Bob Page is a Navy veteran with 25 years of public sector operations, management and federal consulting experience with the Department of Veterans Affairs (VA) and Department of Defense (DoD). He is responsible for VA and DoD client engagement and business development.
He has led various studies and analyses, program evaluations, policy and strategic planning, and technical assistance projects focused on health care and benefits delivery for Veterans and their families. Before that, Page served 13 years with VA in leadership roles.
Page received a Master of Science in Management & Health Care Administration from the University of Maryland.
Erika C. Robbins
Erika Robbins, MA, PMP, vice president, joined The Lewin Group in 2011, leading long-term services and supports projects with federal and state agencies. Prior to joining Lewin, she worked at the Ohio Department of Medicaid for over 10 years.
She has managed and provided oversight over state services, including behavioral health, HCBS waivers, functional eligibility and enrollment processes, data collection and analysis, care coordination and innovative approaches to health and human service delivery.
Robbins received her bachelor’s degree from Hanover College and a master’s degree from the Wright State University Applied Behavioral Science Program. She is a certified project management professional.
Marisa Russo, PhD
Marisa Russo, PhD, joined The Lewin Group in 1998 and specializes in organizational and systems analysis, program monitoring and performance management.
Russo’s work includes the development and provision of training, strategic planning and technical assistance, as well as design and implementation of research and evaluation studies, with an emphasis on maximizing efficiencies and effectiveness of program performance.
Russo’s focus has been on programs addressing the health and educational needs of women and children. She received her doctorate of philosophy in industrial and organizational psychology from George Mason University.
Lisa Shugarman, PhD
Lisa Shugarman is a nationally recognized expert in aging, long-term services and supports (LTSS), end-of-life care, chronic and advanced illness, and Medicare, Medicaid and dual eligible populations.
Shugarman is serving as project director or task lead for high-level federal and state government initiatives including the CMS Medicare Care Choices Model Implementation, which tests new models of care for hospice-eligible Medicare and dual eligible beneficiaries.
She has published 52 papers in peer-reviewed scientific literature and presented at more than 80 national conferences. Shugarman is a graduate of the University of California at Berkeley and received her doctorate from the University of Michigan at Ann Arbor.
Brian Simonson is a biostatistician, with experience analyzing both clinical and economic outcomes in the health care field, and currently serves as a statistical expert for the Center for Medicare and Medicaid Services’ statistical audits of Medicare and Medicaid.
Simonson also has extensive experience in retrospective clinical analyses and pharmacoeconomics. He has served as a senior statistician in a series of retrospective studies analyzing the clinical effectiveness of diabetes and the cost effectiveness of ulcer treatments.
Simonson received a bachelor’s degree in economics and a master’s degree in statistics from the University of Virginia.
Julie Somers, PhD
An economist by training, Julie Somers, PhD, has over a decade of experience working for congressional agencies on health care policy issues. She employs econometric modeling and data analytics to assess the effects of changes in legislation on health care spending.
Through her roles as a senior analyst for the Medicare Payment Advisory Commission and as a principle analyst for the Congressional Budget Office, she gained extensive experience designing and leading analyses of Medicare and private sector claims data.
The focus of her work has been to distill complex analyses of health care systems into readily accessible and understandable formats for a diverse audience, including CMS policy makers, CBO directors, congressional staff, MedPAC commissioners and industry executives.
Nancy Walczak, FSA, PhD
Nancy Walczak, FSA, PhD, acts as an advisor on medical therapies and interventions for a number of private insurance organizations, pharmacy benefit managers and self-funded employer group health plans.
Walczak is a frequent speaker on the topic of the role of medical innovation as a driver of medical inflation at annual meetings of the Society of Actuaries and conferences. Walczak has more than 20 years’ experience in health care analysis and forecasting.
Walczak is recognized by her peers as a leader in the modeling of new, emerging and disruptive developments in the biotechnology and pharma space. She is a fellow of the Society of Actuaries and received her doctorate in neuroscience from Northwestern University.
Chief Operating Officer, The Lewin Group
As chief operating officer, Michael Wentzien oversees operations while shaping the Lewin vision for 2019 and beyond.
He joined Lewin from Optum Advisory Services where he led the growth organization. Over his six-year leadership tenure, the book of business under his responsibility grew 300 percent.
Wentzien has over 25 years of consulting and leadership experience, with 15 years in health care. He led and directed matrixed teams, delivering business solutions that addressed challenges affecting multiple functions and disciplines.
Prior to joining Optum, he worked as a managing consultant for IBM Business Consulting Services. He holds a Bachelor of Arts degree from the University of Iowa.
Shalini Jhatakia has ten years of experience analyzing health care data and managing large projects for clients in the federal government. At Lewin, she works on the Evaluation of the Oncology Care Model, and State Innovations Model All-Payer Operations project.
She earned a master's degree in Economics from the University of California, San Diego, and a bachelor's degree in Economics/Mathematics from the University of Southern California.
Karen Gallegos is an experienced healthcare professional with a background in quality improvement & management, data analysis, and process re-design to achieve operational and client efficiencies.
She has a proven track record of developing and leading initiatives to improve clinical outcomes and efficiency across the health care continuum. She also has experience in designing and adapting clinical systems, developing communication strategies and fostering engagement in change concepts.
Ms. Gallegos has a bachelor's degree from Colorado State University in Fort Collins, Colorado.
Alicia Goroski, MPH, is a Vice President in the Center for Learning and Diffusion. Ms. Goroski is currently directing the learning system contract for CMS' Bundled Payments for Care Improvement Initiative and Comprehensive Care for Joint Replacement Model.
She is also involved in Lewin's work on the Quality Improvement Network National Coordinating Center. Prior to joining Lewin, Ms. Goroski was the Director of Performance Measurement at the Center for Improving Value in Health Care (CIVHC).
Ms. Goroski received her master's degree in Public Health from Rollins School of Public Health at Emory University. Dedicated to improving the delivery of health care services, she has worked in public health and quality improvement for 16 years.
Jaclyn Marshall has over 14 years of experience in the health care industry conducting and managing projects that rely heavily on quantitative analysis, including program monitoring and evaluation contracts.
She specializes on using administrative data, particularly Medicare and Medicaid claims data, to evaluate the impact of health care policies and examine use and cost of health care services among various subpopulations.
She currently serves as the project manager for the Bundled Payments for Care Improvement (BPCI) Advanced Model evaluation contract for the Centers of Medicare & Medicaid Services (CMS). She previously served in a similar role for the BPCI initiative evaluation and monitoring contract.
She works closesly with the Center for Medicare and Medicaid Innovation (CMMI) on applying robust methodologies to estimate the impact of bundled payments on payment, utilization and quality of care. Ms. Marshall has successfully managed many other multi-faceted projects for many federal health agencies including CMS, AHRQ, NIH, IOM, and ASPE as well as large private employers.
She has a master's degree in Health Services Research from the University of Michigan and a bachelor's degree in Applied Mathematics.