Daniel M. Horn, MD is the Director of Population Health for the Division of General Internal Medicine and an Associate Medical Director at the Massachusetts General Physician Organization. Dr. Horn is a primary care physician at Internal Medicine Associates, where he provides comprehensive preventive care, chronic disease management and urgent care to adult patients. Dr. Horn is board certified in Internal Medicine and is an instructor at Harvard Medical School. Dr. Horn is trained in various process improvement methodologies and is certified as an Improvement Advisor by the Institute for Healthcare Improvement.