Nursing is a recognized health sciences profession concerned with "the protection, promotion, and optimization of health and abilities, prevention of illness and injury, alleviation of suffering through the diagnosis and treatment of human response, and advocacy in the care of individuals, families, communities, and populations." One who performs nursing is called a nurse. There are different levels of qualifications, with narrower or wider scopes of practice, for different types of nursing; the term registered nurse is often used to described the basic professional level. Much as there are areas of physician specialization, there are various areas of advanced practice nursing; much as there are various assistants to physicians, there are various types of nursing technicians, orderlies, and other assistants to professional nurses.
While nurses were once considered only adjuncts to physicians practicing medicine, the profession constantly redefines itself. Even though many functions performed by nurses may be only at the order of physicians, the actual performance of the function may be a skill for which nurses are trained and physicians are not.
While the word "doctor" derives from a Latin word meaning "to teach", a major role of professional nurses is education both in dealing with specific disease matters, and also in health maintenance. Various forms of advanced practice nursing cross into areas previously thought part of medicine; the degree of autonomy exercised by advanced practice nurses vary by training and jurisdiction of practice.
Unquestionably, nurses are the authorities on the direct care of hospitalized patients, and exercise considerable training, continuing knowledge, and experience in delivering care. Many of the evaluation and procedures that a "basic" registered nurse routinely performs, such as starting intravenous drug administration, were once considered only within the scope of practice of physicians.
There is conflict between the role of nurses and physicians. Both, for example, will perform medical history-taking and physical examination. While they may draw many of the same conclusions, they often perform the functions to obtain different types of knowledge. In the past, diagnosis was considered strictly within the scope of practice of medicine. The term "nursing diagnosis" is in vogue, and many physicians find it a challenge; they prefer the less ambiguous term "nursing assessment". At a high level, the medical diagnosis is concerned with determining the etiology of illness and the types of treatment required; the nursing assessment is concerned both with the means of delivery of that treatment, but also the general physical, emotional, and social well-being of the patient.
The term "nurse" is often qualified as "registered nurse", to establish that a person has completed the education and certification (i.e., "registration") to perform a core scope of practice.
- American Nursing Association, Definition of nursing