The first educational program for physician assistants opened in 1965 in response to a perceived shortage and maldistribution of physicians. Accordingly, the physician assistant (or physician associate) was initially viewed as a substitute for the doctor; the PA was an individual who, with appropriate supervision, would provide medical care to rural and other medically underserved populations in place of a physician.
Recently, The American Academy of Physician Assistants, the Association of PA Programs and the National Commission on the Certification of Physician Assistants created a document which outlines the Competencies of the Physician Assistant Profession.
Educated in the medical model, a PA is defined by the American Academy of Physician Assistants as "a health professional who practices medicine with the supervision of a licensed physician." Physician utilization of physician assistants creates a unique health care team dedicated equally to 1) increasing accessibility to high quality health care, 2) providing comprehensive health care services, 3) maintaining an atmosphere of caring and trust between the patient, the family, and the health care team, and 4) improving the continuity of patient care within the health care system.
The PA is distinguished from other health care professionals by their education as a generalist, by the breadth of their clinical knowledge, by the extent to which they are given decision-making authority regarding patient care, diagnosis, and treatment, and by the depth of their clinical experience.
PAs practice medicine in all 50 states as well as internationally. As of 2010 all 50 states, the District of Columbia, and Guam have granted PAs licenses to prescribe medicine.