Nursing theory is the term given to the body of wisdom that is used to support nursing practice. In their professional education, nurses will study a range of interconnected subjects which can be applied to the practice setting. This knowledge may come from experiential learning, from formal sources such as nursing research or from non-nursing sources.

Nursing theories provide a framework for nurses to systematize their nursing actions: what to ask, what to observe, what to focus on and what to think about, to develop new and validate current knowledge. They define commonalities of the variables in a stated field of inquiry, guide nursing research and actions, predict practice outcomes, and predict client response.

Nursing theories are used to describe, develop, disseminate, and use previous/present knowledge in nursing. Descriptive theory identifies properties and components of a discipline. They identify meaning and observations and describe what elements exist in that discipline. Explanatory theory identifies how the properties and components relate to each other and accounts for how the discipline functions. Predictive theories predict the relationships between the components of a phenomenon and predict under what conditions it will occur. And, Prescriptive theories address nursing therapeutics and consequences of interventions.

There are generally 4-levels of Nursing Theory: Metatheory is the most abstract and not easily tested. Grand Theory is a conceptual framework that defines broad perspectives for nursing practice. Middle Range Theory is moderately abstract and has a limited number of variables. They can be tested directly. Mid-range is very useful in nursing research and practice. Practice Theory traces the outline for practice. Objectives are set and actions are set to meet the objectives. Four steps in the development of practice theories are: factor isolating, factor relating, situation relating, and situation producing control.

In nursing, theories can also be analyzed by types which are needs, interaction, outcome, and humanistic-focused.

It is interesting to note that 90% of all nursing theories have been generated just in the last 20-years. Many schools encourage students to formulate theories of Nursing as part of their curriculum. In fact the pages of Nursing Science Quarterly are a major mouthpiece for Nursing Theory. Some still argue though that this multiplicity of theory is detrimental to the practice and undermines common vision. Others would say that the nature of the young science is sufficiently far reaching to require such tactics in order to elicit true consensus. It cannot be denied, however, that there is much vanity involved in the formulation of nursing theory.

Nursing theory is essential to the framework of nursing practice. Nursing theory information will assist in guiding individual practice and research methods.