She has studied health care systems, Medicaid, mental health, and populations who interact with the criminal justice system. She has evaluated new types of hospital and physician organizations and their effects on quality, efficiency, costs, prices, and technology adoption. Currently, she is supporting a study panel on addressing pricing power in health care markets and is engaged in an NIH-funded study of employer wellness programs. In other work supported by the National Institute of Mental Health and private foundations, Dr. Cuellar has examined a variety of behavioral health and Medicaid policy issues as they relate to juveniles and adults in the justice systems.