Monday, April 8, 2019
Mining Building Room 128
170 College Street
This event is open to the public and registration is not required. Part of the Operations Research Seminar Series coordinated by Merve Bodur.
About one out of six inmates in the United States (U.S.) is infected with hepatitis C virus (HCV). HCV prevalence in prison systems is ten times higher than the general population, and hence prison systems offer a unique opportunity to control the HCV epidemic.
New HCV treatment drugs are very effective, but providing treatment to all inmates is prohibitively expensive, which precludes universal HCV treatment in prison systems. As such, current practice recommends prioritizing treatment based on clinical and incarceration-related factors, including disease staging, remaining sentence length, and injection drug use (IDU) status. However, there is controversy about how these factors should be incorporated because of the complicated tradeoffs.
In this study, we propose a restless bandit modeling framework to support hepatitis C treatment prioritization decisions in U.S. prisons. We first prove indexability for our problem and derive several structural properties of the well-known Whittle’s index, based on which, we derive a closed-form expression of the Whittle’s index for patients with advanced liver disease. From the interpretation of this closed-form expression, we anticipate that the performance of the Whittle’s index would degrade as the treatment capacity increases; and to address this limitation, we propose a capacity-adjusted closed-form index policy.
We parameterize and validate our model using real-world data from Georgia state prison system and published studies. We test the performance of our proposed policy using a detailed, clinically-realistic simulation model and show that our proposed policy can significantly improve the overall effectiveness of the hepatitis C treatment programs in prisons compared with the current practice and other benchmark policies, including the commonly used Whittle’s index policy.
Our results also shed light on several controversial health policy issues in hepatitis C treatment prioritization in the prison setting and have important policy implications including: 1) prioritization based on only liver health status, a commonly practiced policy, is suboptimal compared with many other policies we consider. Further, considering remaining sentence length of inmates and IDU status in addition to liver health status in prioritization decisions can lead to a significant performance improvement; 2) the decision of whether to prioritize patients with shorter or longer remaining sentence lengths depends on the treatment capacities inside and outside the prison system, and prioritizing patients with shorter remaining sentence lengths may be preferable in some cases, especially if the treatment capacity inside the prison system is not very tight and linkage-to-care level outside prison system is low; and 3) among patients with advanced liver disease, IDUs should not be prioritized unless their reinfection is very-well controlled. Lastly, we introduce and discuss a decision support tool we have developed for practical use.
Turgay Ayer is the George Family Foundation Early Career professor and an associate professor at Industrial and Systems Engineering, and is the research director for healthcare analytics and business intelligence in the Center for Health & Humanitarian Systems at Georgia Tech. In addition, Dr. Ayer holds a courtesy appointment at Emory Medical School.
His research focuses on socially responsible operations and practice-focused research, with a particular emphasis on healthcare analytics. His research papers have been published in top tier management, engineering and medical journals, and covered by popular media outlets, including the Wall Street Journal, Washington Post, US News, and NPR.
Dr. Ayer has received over $2 million grant funding and several awards for his work, including an NSF CAREER Award (2015), first place in the MSOM Best Practice-Based Research Competition (2017), INFORMS Franz Edelman Laureate Award (2017), and Society for Medical Decision Making Lee Lusted Award (2009).
Ayer serves an associate editor for Operations Research and Management Science, and is a past president of the INFORMS Health Application Society. He received a B.S. in industrial engineering from Sabanci University in Istanbul, Turkey, and his M.S. and Ph.D. degrees in industrial and Systems Engineering from the University of Wisconsin – Madison.
The Operations Research (OR) seminar series brings together graduate students, faculty and researchers from the University of Toronto community to interact with prominent scholars in the field of OR. Seminars feature visiting scholars from around the world as well as professors and post-docs. Topics include all variants of OR theory and their applications. Questions? Contact Merve Bodur at firstname.lastname@example.org