An increasing number of people seek medical attention for mild cognitive symptoms at older age, worried that they might develop Alzheimer's disease. Some clinical practice guidelines suggest offering biomarker testing in such cases, using a brain scan or a lumbar puncture, to improve diagnostic certainty about Alzheimer's disease and enable an earlier diagnosis. Critics, on the other hand, point out that there is no effective Alzheimer treatment available and argue that biomarker tests lack clinical validity. The debate on the ethical desirability of biomarker testing is currently polarized; advocates and opponents tend to focus on their own line of arguments. In this paper, we show how the method of reflective equilibrium (RE) can be used to systematically weigh the relevant arguments on both sides of the debate to decide whether to offer Alzheimer biomarker testing. In the tradition of RE, we reflect upon these arguments in light of their coherence with other argumentative elements, including relevant facts (e.g. on the clinical validity of the test), ethical principles, and theories on societal ideals or relevant concepts, such as autonomy. Our stance in the debate therefore rests upon previously set out in-depth arguments and reflects a wide societal perspective.

Background Patient, public and participant involvement (PPPI) is increasingly acknowledged as a key pillar of successful research activity. PPPI can influence recruitment and retention, as well as researcher experience and contribute to decision making in research studies. However, there are few established methodologies of how to set up and manage PPPI activities. Methods In this paper we describe the set-up, running and experiences of the EPAD participant panel. The EPAD study was established as a pan-European cohort study aiming at understanding risks for developing Alzheimer’s disease and building a readiness cohort for Phase 2 clinical trials. Due to the longitudinal nature of this study, combined with the enrolment of healthy volunteers and those with mild cognitive impairments, the EPAD team highlighted PPPI involvement as crucial to the success of this project. The EPAD project employed a nested model, with local panels meeting at least twice a year established in England, France, Scotland, Spain and The Netherlands, feeding into a central panel who met once a year at the project’s General Assembly. The local panels were governed by terms of reference which were adaptable to meet local needs. We discuss the recruitment opportunities employed by the centres and the set-up of the panels. Results Impact of the panels has been widespread, and varies from feedback on documentation, to supporting with design of media materials and representation of the project at national and international meetings. Conclusions The EPAD panels have contributed to the success of the project and the model established is easily transferable to other disease areas investigating healthy or at-risk populations.