John Malcolm Hollingsworth MD, MS - Principal Investigator

Dr. Hollingsworth is a Professor of Urology. He received his medical degree from Georgetown University in 2002. Following completion of his urology residency (2002-2008), he entered the Robert Wood Johnson Foundation Clinical Scholars Program (2008-2010). Since joining the University of Michigan faculty in 2010, Dr. Hollingsworth's clinical practice has focused on the medical and surgical management of urinary stone disease. He co-directs the University’s multidisciplinary stone clinic. Using the shared medical appointment model, this clinic brings together experts in Urology, Nephrology, and Nutrition.

In addition to delivering state-of-the-art clinical care, Dr. Hollingsworth maintains a robust research agenda that encompasses a broad range of health services disciplines. He has investigated the effect of physician financial incentives on utilization. He has also examined the relationship between variation in provider practice and the quality and costs of urological care. His current line of inquiry explores the interface between primary and specialty care. With funding from AHRQ, NIDDK, and NIA, he is investigating how the incorporation of specialist physicians into Medicare payment reforms influences program performance and the comparative effectiveness of different preventive pharmacological therapy agents for urinary stone disease, respectively.

Institutionally, Dr. Hollingsworth serves as the Medical Director for Clinical Quality and Interim Medical Director for Clinical Design and Innovation. His group offers a variety of services, including clinical guidance development, project management support for Michigan Medicine’s quality improvement committees, administrative support for the Blue Cross Blue Shield of Michigan-funded collaborative quality initiative coordinating centers, and coaching for Maintenance of Certification Part IV. He also chairs Michigan Medicine’s Quality Council. Regionally, Dr. Hollingsworth co-directs the Michigan Urological Surgery Improvement Collaborative’s Reducing Operative Complications from Kidney Stones initiative.



Phyllis Yan

Phyllis joined the HSR division in 2015, primarily working with Medicare data. Her specialties include large data analysis and mixed models. In her spare time, Phyllis is a dodgeball pro.


Mary Oerline

Ms. Oerline joined the HSR division in 2016. She has co-authored many papers published in peer-reviewed journals and contributed to abstracts presented at major scientific meetings.


Addison Shay



Laura Woodman

Laura provides administrative support to Dr. Kristin Chrouser, Dr. Khurshid Ghani, Dr. John Hollingsworth and Dr. Ted Skolarus. She is also the fellowship coordinator for the HSR fellowships.


Research Associate

Sitara Murali

Sitara is a Research Associate for the Dow Division of Health Services Research in the Department of Urology. She provides research and project management support to Dr. Hollingsworth. Sitara graduated from the University of Michigan School of Public Health with a Bachelor of Science in Public Health Sciences in 2020.