How can trust be investigated? Drawing lessons from past experience.

Although the concept of trust has gained popularity in public debate and academic analysis over recent years, it continues to be regarded by many as difficult to define and so to investigate. In this paper we provide guidance on how to conduct future work on trust in the health sector, by reviewing the methods used in earlier studies. The paper draws on a range of the available literature which investigates trust in different settings from a variety of disciplinary perspectives. The review suggests that appropriate definitions of trust are highly context dependent. Where little is known about how trust functions, qualitative research to explore how respondents view trust and 'trusted' behaviour is important in advance of quantitative investigation. The results of qualitative inquiry facilitate the development and refinement of hypotheses about how trust functions and can be used to generate questions for use in structured questionnaires. Quantitative inquiry is valuable because it allows larger scale investigation and generates data that can be used, for example, to assess the statistical significance of different determinants to overall levels of trust. The review indicates that trying to use existing data to answer a new research question, without ensuring that respondents' answers refer to the form of trust under investigation, may lead to the generation of use of inappropriate data. In this respect, it highlights the need to test pre-existing research tools to ensure that they remain valid and relevant and retain their reliability in different settings. Although there may appear to be common structural features of specific relationships that might allow international measurement tools to be developed for use in the same type setting across geographical locations, cultural differences might invalidate such tools. Specific investigation of such differences is, therefore, needed to explore the potential validity of international tools for investigating trust.