Middle-range theories as models: New criteria for analysis and evaluation.

This essay argues for a new perspective on the analysis and evaluation of middle-range theory. The commonly used criteria for theory evaluation in nursing are not as useful as they should be, and the root of the problem is an inappropriate understanding of middle-range theory. In spite of their name, middle-range theories should not be analysed and evaluated as concrete or limited versions of more general theories. Rather, they are best understood as models. The latter sections of this essay present a new method for analysing middle-range theories and new criteria for their evaluation. Analysing and evaluating theories relevant to nursing as models has the capacity to increase their scholarly and clinical usefulness.