William J. Parish

Will Parish is a Health Economist at RTI who leads the quantitative impact analyses to evaluate a Centers for Medicare & Medicaid Services-funded model developed to address social determinants of health in health care outcomes. He oversees a team of analysts and claims data programmers who work with multiple claims databases associated with Medicaid, Medicare fee-for-service, and Medicare Advantage populations. In addition, Dr. Parish is a co-investigator on a National Institute on Alcohol Abuse and Alcoholism R01 research grant to develop a novel Bayesian technique for measuring alcohol exposure distributions in the United States that account for misclassification errors in self-reported survey data. This project aims to create more reliable evidence on the burden of illness associated with alcohol use in the United States and provide research techniques applicable to other national and global contexts.

In addition, he serves as the project director for a small research grant funded through a partnership with an advocacy group to study the prevalence of unmet substance use disorder treatment needs among Medicare beneficiaries. This study builds off multiple groundbreaking research studies that highlighted barriers to opioid use disorder treatment access among Medicare patients.