The role of the nurse varies with the needs of the client, the nurse's credentials, and the type of employment setting. An RN assesses a client's health status, identifies health problems, and develops and coordinates care. A licensed vocational nurse (LVN), in some states known as a licensed practical nurse (LPN), provides direct client care under the direction of an RN, physician, or other licensed practitioner. As nursing roles have expanded, new dimensions for nursing practice have been established. Nurses can pursue a variety of practice specialties (e.g., critical care, mental health, oncology). Advanced practice registered nurses (APRNs) provide direct client care as NPs, nurse midwives, certified registered nurse anesthetists, and clinical nurse specialists. These nurses have education and certifications that—depending on state regulations—may allow them to provide primary care, prescribe medications, and receive third-party (insurance) reimbursement directly for their services.