Patient and public involvement - experiences from a Danish peer-mentor complex intervention project

In health research, there is a growing tendency to involve patients and members of the public as partners in research. This approach to patient involvement is known as 'Patient and public involvement' (PPI). In Denmark, different approaches to PPI are utilized. Guidelines and empirical examples are warranted. The aim of this essay is to report the preliminary experiences with PPI in an ongoing research project 'Heartened' (in Danish: 'HjertensGlad') and to discuss the methodological implications of using PPI in the development of a complex intervention. In this essay, we provide empirical examples of how PPI can be used in 1) Development of a complex intervention, 2) Recruitment of research participants, 3) Development of written material, 4) Validation of results, and 5) for dissemination of scientific results. PPI have contributed substantially in IljertensGlad' and helped developing the project. There are many advantages of using PPI in research. However, researchers must be apt to work with research in a new way if they initiate a PPI collaboration.