The discovery of unique nurse practitioner theory in the literature: seeking evidence using an integrative review approach.

Purpose: To determine if theory unique to nurse practitioners (NPs) exists and to describe the attributes of such theory.

Data sources: An integrative review of the literature was used. CINAHL and MEDLINE were searched using key terms such as nurse practitioners, theory, or research. Forty-five articles contributed to the final analysis.

Conclusions: The NP role evolved from nursing yet is heavily influenced by medicine. This integration may affect both the use of theory in NP literature and the types of theories that are used to guide NP literature generation and research. Evidence was found of emerging theory unique to NPs with theoretical origins grounded in nursing, medicine, and social science.

Implications for practice: NPs are beginning to develop theories of "nurse practitionering." This development is imperative for NP education, practice, and research to further the knowledge of the discipline and to help articulate the unique body of knowledge possessed by NPs.