gms | German Medical Science

Background: Dementia Special Care Units (DSCU) provide care for people with dementia who exhibit complex psychiatric symptoms and severe behavioral problems like agitation, aggression or wandering. DSCUs are frequently operated as segregated units within a nursing home; they offer a dementia-specific activity program, the staff is specially trained and the environment is adapted to the needs of people with cognitive impairments. Provided that the nursing home has negotiated higher staff ratios with the cost bearers, the staff-to-resident ratios in DSCUs are higher compared to other units. In the practice, the infrastructure and performance of DSCUs vary to a great extent; also because of different legal regulations in the federal states and the strong influence of municipal decisions. Because of the different elements that constitute a DSCU, they can be regarded as a complex health care program that is nowadays implemented in approximately 50% of all German nursing homes. Despite their high implementation degree and the additional costs they cause, DSCU evaluation studies from Germany are scarce. Evaluation studies of DSCUs face the challenges that randomization is neither practical nor ethical and that due to the variety in their characteristics, DSCUs are hardly comparable. Predominant research models seem too simplistic to reflect the complexity that is inherent in this field of health service research. Therefore, alternative research frameworks and methodologies are needed to explore complex relationships in DSCUs. The realist evaluation approach by Pawson & Tilley (1997) is a theory-driven multi-method generic approach that goes beyond the experimental paradigm by providing an in-depth exploration of generative causal mechanisms and their social and contextual influences (Salter & Kothari, 2014).

Objective: This realist evaluation aims to identify and explain which aspects of DSCUs are working, for whom, and under what circumstances the outcomes intended are reached. The evaluation will lead to a middle-range theory of relationships between contextual factors, mechanisms and outcomes of DSCUs.

Methods: This multi-method study will be conducted in four phases. Phase 1 will lead to the development of an initial program theory that contains testable descriptions of the context, mechanisms and outcomes (CMOs) and proposes assumptions about their relationship. Therefore, a rapid realist review of different sources of literature will be conducted. Review findings will be enriched with data that were generated in expert interviews with program stakeholders. In Phase 2, the initial program theory will be evaluated and CMO-configurations will be refined. Therefore, a survey study will be used to describe the context of implemented DSCUs. Based on the descriptive data distinctive types of DSCUs that differ with regard to contextual factors will be developed. DSCUs of different types will be investigated further within a multiple case study. For the multiple case study in-depth interviews with nursing staff, family members and residents, non-participant observation and an environmental audit at each site will be conducted. For the outcome evaluation a longitudinal retrospective cohort analysis will be performed using routinely collected data. Qualitative data of the multiple case study will be analyzed thematically applying a deductive analytical approach. The initial program theory will provide the coding framework but qualitative data may also identify emergent categories. The quantitative data from the cohort study will be analyzed using Kaplan-Meier methods. In Phase 3, empirically derived CMO-configurations from the different DSCUs will be compared within a cross-case analysis to scrutinize pre-developed assumptions of what works, for whom and under what circumstances. As a result of the synthesis process, the initial program theory will be refined and generalized.

Results: The results of the study are intended to inform providers of DSCUs and policymakers about contextual aspects that are needed to facilitate an effectively working DSCU and which mechanisms enhance or hinder their successful implementation. The results will also inform about the question for whom which DSCU model may be the most beneficial.