What is a theory?

There's nothing so practical as a good theory. A theory is a set of conceptual tools that enable us to describe, explain, and make claims about aspects of the world we live in. Theories enable us to do three kinds of conceptual work:

1. Accurate description. A theory must provide a taxonomy or set of definitions that enable the identification, differentiation, and codification of the qualities and properties of cases and classes of phenomena.

NPT systematically establishes and differentiates the phenomena with which it is concerned by defining actors, objects and contexts, and the processes that govern them. It therefore permits a rational foundation for explanations of observed events and processes pertaining to the implementation of new technologies and complex interventions in health care systems.

2. Systematic explanation. A theory must provide an explanation of the form and significance of the causal and relational mechanisms at work in cases or classes of the phenomena defined by the theory, and should propose their relation to other phenomena.

NPT offers a systematic explanation of the operation of those processes and conditions by referring to patterns of action that can be empirically shown to affect their outcomes, and by defining the causal mechanisms and relations that underpin these. It may thus be reasonably employed to make predictions about the normalization potential of proposed technologies or interventions, and about the possible outcomes of other implementation processes.

3. Knowledge claims. A theory must lead to knowledge claims. These may take the form of abstract explanations, analytic propositions, or experimental hypotheses. They may also map relations with other phenomena that are believed to possess similar qualities and properties.

NPT permits verifiable knowledge claims about process and action, and proposes a set of analytic propositions that can inform empirical investigation. This means that it not only accounts for outcomes of implementation processes, but can also account for differences between expected and observed outcomes of new technologies or complex interventions in real health care settings.

A fourth, but not mandatory, component of a theory is that it proposes a means of testing its knowledge claims. A theory must be testable. Such tests may be abstract (i.e. formal logical representations, simulations, or thought experiments); or concrete (empirical investigations).