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Mary Creten (van der Heijde), FSA, MAAA

Principal, Consulting Actuary
Denver, CO, US

Tel: +1 303 2999400

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Professional Designations

  • Fellow, Society of Actuaries
  • Member, American Academy of Actuaries


  • BS (with highest distinction) in Applied Mathematics, University of Colorado at Boulder
  • Certificate in Actuarial Sciences, University of Colorado at Boulder

Current Responsibility

Mary is a principal and consulting actuary with the health practice in the Denver office of Milliman. She joined the firm in 2001.


Mary has been heavily involved in healthcare reform, with focus both on current required changes and on pricing and strategy for entry to health exchanges. Mary works extensively on individual and small group underwriting and pricing and leads the development of Milliman's Small Group Medical Underwriting Guidelines and Individual Medical Underwriting Guidelines products for the United States, Brazil, and Mexico. She has recently done significant work assisting insurers in the individual market, including pricing, design, medical underwriting implementation, and other market and competitive considerations. She has also worked in areas of predictive modeling, including risk adjusters, lifestyle based analytics, and other tools to enhance initial underwriting.

She has considerable experience in pricing, having worked intensively on pricing healthcare costs for the federal government's multi-billion dollar TRICARE program. In addition, she has done extensive work in litigation support for Medicaid rate setting expert witness cases. She has also worked for the Center for Medicare and Medicaid Services (CMS) as a part of Milliman's ACRP Audit team. She has ample experience in statistical and longitudinal data analysis. Mary also helped in development of the book True Group Long-Term Care and has worked in long-term care modeling and pricing. Her recent projects include plan utilization rate development for large insurers, researching and pricing changes in benefit coverage, and plan analysis.

  • Work at Milliman

    • “I was offered a chance to come in, shake things up, create something."
    Work at Milliman