Empirical tests of the Neuman systems model: relational statement analysis.

To be a valid test of the Neuman systems model, researchers' relational statements must be congruent with Neuman's axioms and must also be congruent at the conceptual, theoretical, and operational levels. Guided by Cooper's five-stage integrative review method, 92 quantitative research studies (dissertations and journal articles) were collected and categorized according to an expanded version of Silva's levels of theory testing. Nine studies, with explicit relational statements, were analyzed at three levels of abstraction, and interpretations of the studies' results were explored. Recommendations are made for the establishment of a program of research.