[Development of a program theory as a basis for the evaluation of a dementia special care unit]

Background: An existing dementia special care unit should be evaluated. In order to build a sound foundation of the evaluation a deep theoretical understanding of the implemented intervention is needed, which has not been explicated yet. One possibility to achieve this is the development of a program theory. Aim: The aim is to present a method to develop a program theory for the existing living and care concept of the dementia special care unit, which is used in a larger project to evaluate the concept theory-drivenly. Method: The evaluation is embedded in the framework of van Belle et al. (2010) and an action model and a change model (Chen, 2015) is created. For the specification of the change model the contribution analysis (Mayne, 2011) is applied. Data were collected in workshops with the developers and the nurses of the dementia special care unit and a literature research concerning interventions and outcomes was carried out. The results were synthesized in a consens workshop. Results: The action model describes the interventions of the dementia special care unit, the implementers, the organization and the context. The change model compromises the mechanisms through which interventions achieve outcomes. Conclusions: The results of the program theory can be employed to choose data collection methods and instruments for the evaluation. On the basis of the results of the evaluation the program theory can be refined and adapted.