Clinical and Economic Research

3M Health Information Systems


Developed by 3M, APR DRGs stands for All Patient Refined Diagnosis Related Groups, a classification system designed to accurately identify how sick a patient population is compared to peer organizations. 3M APR DRGs are an extension of the basic DRG structure that reflects the complete cross-section of patients seen in an acute care setting. The 3M APR DRGs include four severity-of-illness levels and four risk-of mortality levels within each DRG. Severity and mortality subclasses are assigned according to a sophisticated clinical logic that simultaneously evaluates the interactions of multiple co-morbidities, age, procedures, and principal diagnosis. The idea behind APR DRGs is that severity of illness and risk of mortality both depend on the patient’s underlying condition. High severity of illness and risk of mortality are characterized by multiple serious diseases and the interactions between disorders.

3M Commentary

Where we’ve been and where we’re going: A 50-year perspective on health policy

By Megan Carr, Chet Stroyny

I recently had the opportunity to talk with Chet Stroyny, a program manager for Regulatory and Government Affairs at 3M…

Research Study

Geographic Variation in Hospital Admission Rates in the Medicare Population

With Richard Averill, MS, Richard Fuller, MS, Ron Mills, PhD

Health care expenditures continue to steadily increase with hospital stays making up about one-third of health care expenditures. A well-functioning…

Journal Article

Importance of coding co-morbidities for APR-DRG assignment: Focus on cardiovascular and respiratory diseases

Published by the Health Information Management Journal, May 2019, by Julio Souza, João Vasco Santos, MD, Veronica Bolon Canedo,…

Journal Article

IR-DRGs and CDI in the UAE

Published in the Journal of AHIMA, April 2019,  by Wilbur Lo, MD, CDIP, CCA.  Clinical documentation improvement (CDI) holds…

Journal Article

Moving toward paying for outcomes in Medicaid

With Kevin Quinn, MA, EMT-P, Norbert Goldfield, MD

Published by The Journal of Ambulatory Care Management, April/June 2018,  by Billy Millwee MHA; Kevin Quinn MA, EMT-P; Norbert…


Factors Affecting the Development of Medicaid Hospital Payment Policies–Findings from Structured Interviews in Five States

Published by Medicaid and CHIP Payment and Access Commission, 2018,  by Thomas Marks, Kathy Gifford, Steven Perlin, Melisa Byrd, and…

Journal Article

Validation of the All Patient Refined Diagnosis Related Group (APR-DRG) risk of mortality and severity of illness modifiers as a measure of perioperative risk

Published in the Journal of Medical Systems, March 2018,  by McCormick PJ, Lin HM, Deiner SG, Levin MA. The…


Maryland: Final Recommendation for the Hospital-Acquired Conditions Program for Rate Year 2020

Published by Health Services Cost Review Commission This is a final recommendation for the RY 2020 Maryland Hospital-Acquired Conditions (MHAC)…


Arkansas: DRG Conversion Plan

Published by Navigant Consulting, Inc. This report provides a Conversion Plan to the Arkansas Department of Human Services (DHS) for…

Journal Article

Evolution of the International Refined Diagnosis Related Groups (IR-DRGs) from Version 1.0 to Version 3.2

Published by AHIMA World Congress, September 2017,  by Marc Berlinguet, MD; Sue Boucher; and JulieAnne Perry. The IR DRGs…