Dr. Rebecca Arden Harris, MD, is a primary care physician on faculty in the Penn Department of Family Medicine and Community Health. A graduate of Haverford College (BSc in Biology), she attended medical school at Thomas Jefferson University and completed residency at Montefiore Medical Center in New York. Before medical school, Rebecca was a research assistant in labs at the Fox Chase Cancer Center and the University of Pennsylvania where she investigated the immune response to hepatitis B and C viruses. At Jefferson and Montefiore, Rebecca studied antiretroviral medication adherence among HIV-positive persons who were experiencing homelessness. She also constructed and validated an instrument for predicting treatment interruptions of HIV medication. Her recent research has focused on opioid prescribing in primary care, and has compared the extent to which different agents (hydrocodone and oxycodone) induce long-term use and dependency. Rebecca plans to expand this focus to include the impact of insurance and out-of-pocket costs on prescription patterns and health outcomes. On the treatment side, Rebecca is interested in the design and evaluation of interventions for opioid use disorder.