Review of research related to Kristen Swanson's middle-range theory of caring.

The aim of this study was to identify and describe how Kristen Swanson's middle-range theory has been used in nursing practice/research presented in international journals. A total of 120 studies were included in the review and 23 were analysed further. An overview of the studies is presented, followed by four categories of how the theory has been used: referring to the theory (97 papers), applications of the theory to practice/research and/or theoretical discussions (nine papers), relating findings to and/or validation of the theory (eight papers), and development of measurements from and/or testing of the theory (six papers). The use of the theory and conclusions of the studies related to criteria for evaluation of theories were discussed.