While M.D.'s and D.O.'s may use all accepted methods of treatment, including drugs and surgery, D.O.'s place special emphasis on the body's musculoskeletal system, preventive medicine, and holistic patient care. About one third of M.D.s are primary care physicians. They practice general and family medicine, general internal medicine, or general pediatrics and are usually the first health professionals patients consult Primary care physicians tend to see the same patients on a regular basis for preventive care and to treat a variety of ailments. General and family practitioners emphasize comprehensive health care for patients of all ages and for the family as a group. Those in general internal medicine provide care mainly for adults who have a wide range of problems associated with the body's organs.
General pediatricians focus on children's health.
D.O.'s are more likely to be primary care providers than allopathic physicians, although they can be found in all specialties. Many physicians work long, irregular hours. They must travel frequently between office and hospital to care for their patients. Increasingly, physicians practice in groups or health care organizations that provide back-up coverage and allow for more time off. Physicians who are on-call deal with many patients' concerns over the telephone, and may make emergency visits to hospitals.