PAs are formally trained to provide diagnostic, therapeutic, and preventive health care services, as delegated by a physician.   They take medical histories, examine and treat patients, order and interpret laboratory tests and x rays, and make diagnoses. They also treat minor injuries, by suturing, splinting, and casting. PAs record progress notes, instruct and counsel patients, and order or carry out therapy. Physician assistants work under the supervision of a physician, however, PAs may be the principal care providers in rural or inner city clinics where a physician is present for only one or two days each week.

Learn more from the US Bureau of Labor Statistics Occupational Outlook Handbook...