The Doctor of Philosophy in Nursing Science program prepares scientists capable of advancing nursing practice and education through research and scholarly activity. Rigorous research training is offered for persons contemplating careers in academia or in health agencies in which designing, planning, and implementing research is a significant expectation. The conceptual base of the program is grounded in nursing science, which seeks to define conditions that are requisite to promote, restore, and maintain health. There are two major interrelated functions: (1) to extend knowledge of various circumstances and environments that influence and alter health (of individuals, groups and populations), and (2) to incorporate theories that identify conditions necessary and sufficient for promoting, restoring, and maintaining states of health.

Nursing provides services that assist individuals and/or populations toward the achievement of health and health-directed behaviors. Services of this nature must be based on systematic knowledge about humans in interaction with their life situations with emphasis on understanding the kinds of environments (both internal and external) that are optimum for the promotion, maintenance, and restoration of states of health, at both microscopic and macroscopic levels. This systematic knowledge base is the foundation of nursing science and incorporates:

1. identification of nursing phenomena and nursing actions relevant to the phenomena;
2. testing of actions and therapies; and
3. use of the results in building various levels of nursing science theories. According to the ANA, 'Nursing's Social Policy Statement', 1995:

The knowledge base for nursing practice is derived from multiple sources, including nursing science, philosophy, and ethics, and physical, economic, biomedical, behavioral, and social sciences. To expand the knowledge base of the discipline, nurses generate and utilize theories and research findings that are relevant to nursing practice and fit with nursing's values about health and illness."