Case study methodology in tissue viability. Part 1: Methodological considerations.

Abstract

Case studies are often presented in relation to tissue viability problems. Within hierarchies of evidence, case studies are sometimes seen to be on a par with expert opinion. This paper examines the case study as a research method and seeks to determine its value in tissue viability research. The term 'case study' denotes a general strategy for research where several methods of data collection are used to provide an in-depth analysis of an individual, group or institution. Three types of case study are used in research: intrinsic, instrumental and collective. All case studies utilize data triangulation within their design, that is, the use of a variety of sources of data within a study. It is one of the major strengths of the case study method. Data sources include documentary data sources, observation and interviews. As in any research, validity and reliability are important in case study methodology; in particular, construct validity, internal validity and external validity. Case studies are potentially vulnerable to observer error and observer bias. Examples are given of potential case studies in tissue viability and their strengths and weaknesses. If undertaken prospectively, with clearly defined multiple sources of data collection and a documented chain of evidence, case studies can add breadth to our knowledge and experience of caring for patients with tissue viability problems.