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May 9, 2011

Risk Adjustment Software to Support Health Care Reform

The Johns Hopkins Bloomberg School of Public Health is launching an updated version of the Johns Hopkins ACG® (Adjusted Clinical Groups) System to support federal health care reform. Developed in 1991, the ACG System is an industry standard risk adjustment and predictive modeling software originally developed by a team of researchers from the Bloomberg School. The updated “ACG-HIE” software will be distributed to the newly formed state Health Insurance Exchanges (HIEs) and to health plans currently under contract with these Exchanges. This innovative technology will be distributed at no cost to facilitate health care insurance reform and encourage equitable care.

“A key provision of federal health reform is the establishment of state-level health insurance exchanges,” said Jonathan Weiner, DrPH, executive director of the ACG team and a professor with the Bloomberg School’s Department of Health Policy and Management. “Uninsured persons will be able to get subsidized insurance through these exchanges whether or not they have any pre-existing medical conditions.  When setting payment rates for the private health plans that will insure people in these HIEs, the differences in the medical needs of the persons selecting different plans must be accounted for.  Without such ‘risk adjustment,’ the health insurance exchange and possibly health reform itself could fail as some health plans may go under and others get large windfalls.” 

The updated ACG-HIE software is based on the Johns Hopkins ACG Risk Adjustment System, a computer-based algorithm that assesses the health of people enrolled in a given health plan or health system. Government agencies or health plans, in turn, use the ACG System to help predict the need for their future health care services.  Today, ACGs help finance and manage the care of more than 80 million people globally and is currently being used by 16 State Medicaid agencies. The Bloomberg School has a full time team of faculty, clinicians and staff dedicated to research, development and maintenance of the ACG System and are currently developing the 11th version of ACGs. 

"The reason we continue to develop and disseminate the ACG tool is to help promote equitable, effective and efficient health care in the U.S. and around the globe,” Weiner adds. "The nation is about to embark on the biggest reform of our health insurance system in history. Making sure that plans covering persons with high levels of medical needs are adequately reimbursed is key to the success of this reform.”

DST Health Solutions, LLC will support and distribute this free version of the ACG software to state health insurance exchanges on behalf of the University. For more information on Johns Hopkins ACGs and the special HIE version of the software, go

About the Johns Hopkins Bloomberg School of Public Health
As a leading international authority on public health, the Johns Hopkins Bloomberg School of Public Health is dedicated to protecting health and saving lives. Every day, the School works to keep millions safe from illness and injury by pioneering new research, deploying its knowledge and expertise in the field, and educating tomorrow’s scientists and practitioners in the global defense of human life. Founded in 1916 as part of the Johns Hopkins University, the Bloomberg School of Public Health is the world’s oldest and largest independent school of public health, with over 2,000 students from 78 countries. For more information, visit

About DST Health Solutions
DST Health Solutions, LLC delivers systems and services that help improve efficiency, reduce operational costs, increase speed to market, and facilitate medical cost management and price containment. Our clients include commercial health plans, consumer-directed plans, government plans (Medicare Advantage, Medicare Part D and Medicaid) and physician practices. DST Health Solutions’ enterprise applications and outsourcing services include claims processing, member and provider management, benefit plan management, new product development, care management and medical management, and decision support/analytics. DST Health Solutions is a wholly-owned subsidiary of DST Systems, Inc. For more information about DST Health Solutions, contact 800.272.4799, email or visit

Public Affairs media contact: Natalie Wood-Wright at 410-614-6029 or