Justin Dimick

Justin Dimick, MD, MPH

George D. Zuidema Professor of Surgery
Chief of the Division of Minimally Invasive Surgery
Associate Chair for Strategy & Finance


Dr. Dimick, Professor of Surgery and Health Policy & Management, serves as the Chair of the Department of Surgery at the University of Michigan. He is a national leader in surgical outcomes research, with over 250 peer-reviewed publications addressing performance measurement, policy evaluation, and collaborative quality improvement.

With funding from the National Institutes of Health (NIH), his current research is evaluating Center for Medicare and Medicaid Services (CMS) policies aimed at improving surgical care, including those aimed at non-payment for adverse events (hospital acquired conditions and readmissions), episode-based bundled payments, and accountable care organizations. With funding from the Agency for Healthcare Research and Quality (AHRQ) and National Institutes of Health (NIH), Dr. Dimick is conducting a statewide study evaluating the impact of video-based coaching to improve individual surgeon performance in bariatric surgery.

Dr. Dimick is currently Chair of the Health Services Organization and Delivery (HSOD) study section at the NIH Center for Scientific Review. He has served as an advisor on issues related to quality measurement and policy evaluation for the Medicare Payment Advisory Committee (MedPAC), the Institute of Medicine (IOM), The Leapfrog Group, and the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP).


Obesity surgery scientist training program T32 1T32DK108740 (Dimick, PI, Co-PI with Seeley) 7/1/16 - 6/30/21 - This grant aims to train the next generation of surgeon-scientists focused on key questions in understanding and improving bariatric surgery, including basic, clinical, and health services questions.

Evaluating policies for improving surgical care in the elderly R01 AG039434 (Dimick, PI) 9/1/16 – 8/31/21 - National Institute of Aging (NIA) - The specific aims of this project are to evaluate the relative effectiveness of several competing policy options for improving care and reducing costs in surgical patients.

Long term comparative effectiveness of laparoscopic sleeve gastrectomy R01 DK115408 (Dimick, PI) 8/1/18 - 4/3/22 - The specific aims of this project are to use insurance coverage for sleeve gastrectomy as an instrumental variable to compare the long-term safety and health care use of sleeve gastrectomy vs. gastric bypass, the gold-standard weight loss procedure. 

Using video analysis to improve outcomes of laparoscopic colectomy R01 HS025365 (Dimick, PI) 9/15/18 - 7/31/23 - The specific aims of this project are to use operative videos to understand best techniques for laparoscopic colectomy and implement them statewide to improve outcomes across Michigan. 

Published Articles or Reviews

Dimick JB, Welch HG, Birkmeyer JD. "Surgical mortality as an indicator of hospital quality: The problem with small sample size." JAMA 2004;292:847-851.

Ghaferi AA, Birkmeyer JD, Dimick JB. "Variation in hospital mortality associated with inpatient surgery." N Engl J Med 2009;361:1368-1375.

Dimick JB, Staiger DO, Birkmeyer JD. "Ranking hospitals on surgical mortality: the importance of reliability adjustment." Health Serv Res 2010;45:1614-1629.

Ryan AM, Nallamothu BK, Dimick JB. “Medicare's public reporting initiative on hospital quality had modest or no impact on mortality from three key conditions.” Health Affairs 2012;31:585-592.

Dimick JB, Staiger DO, Osborne NH, Nicholas LH, Birkmeyer JD. “Composite measures for rating hospital quality with major surgery.” Health Serv Res 2012;47:1861-1879.

Dimick JB, Nicholas LH, Ryan AM, Thumma JR, Birkmeyer JD. “Bariatric surgery complications before vs after implementation of a national policy restricting coverage to centers of excellence.” JAMA 2013;309:792-799.

Dimick JB, Ruhter J, Sarrazin MV, Birkmeyer JD. “Black patients more likely than whites to undergo surgery at low-quality hospitals in segregated regions.” Health Affairs 2013;32:1046-1053.

Osborne NH, Nicholas LH, Ryan AM, Thumma JR, Dimick JB. “Association of hospital participation in a quality reporting program with surgical outcomes and expenditures for Medicare beneficiaries.” JAMA 2015;313: 496-504.

Chhabra KR, Dimick JB. “Hospital Networks and Value-Based Payment: Fertile Ground for Regionalizing High-Risk Surgery.” JAMA 2015;314:1335-1336.

Ibrahim AM, Hughes TG, Thumma JR, Dimick JB. “Association of Hospital Critical Access Status With Surgical Outcomes and Expenditures Among Medicare Beneficiaries.” JAMA 2016;315:2095-2103.

Nathan H, Thumma JR, Ryan AM, Dimick JB. "Early Impact of Medicare Accountable Care Organizations on Inpatient Surgical Spending." Ann Surg. 2019 Feb;269(2):191-196. 

Chhabra KR, Dimick JB. "Surprise Out-of-Network Medical Bills." JAMA. 2020 Mar 3;323(9):902. 

Chhabra KR, Telem DA, Chao GF, et al. "Comparative Safety of Sleeve Gastrectomy and Gastric Bypass: An Instrumental Variables Approach" Ann Surg. 2020;10.