Dr. Marrero received a B.A. (1974), M.A. (1978) and Ph.D. (1982) in Social Ecology from the University of California, Irvine. He joined the IU School of Medicine in 1984 and became the J. O. Ritchey Professor of Medicine in 2004. He was a member of the Diabetes Research & Training Center and served as Director of the Diabetes Prevention and Control Division.
Dr. Marrero is an expert in the field of clinical trials in diabetes and translation research which moves scientific advances obtained in clinical trails into the public health sector. He helped design the Diabetes Prevention Program and the TRIAD study, which evaluated strategies to improve diabetes care delivery in managed care settings. His research interests include strategies for promoting diabetes prevention, care settings, improving diabetes care practices used by primary care providers, and the use of technology to facilitate care and education.
Dr. Marrero was twice awarded The Allene Von Son Award for Diabetes Patient Education Tools by the American Association of Diabetes Educators, nominated to Who's Who in Medicine and Health Care in 2000, and served as Associate Editor for Diabetes Care (1997-2002). Dr. Marrero was selected as the 2008 Outstanding Educator in Diabetes by the American Diabetes Association.