RT Journal Article SR Electronic T1 The Participatory Zeitgeist: an explanatory theoretical model of change in an era of coproduction and codesign in healthcare improvement JF Medical Humanities JO J Med Humanit FD BMJ Publishing Group Ltd and Institute of Medical Ethics SP medhum-2017-011398 DO 10.1136/medhum-2017-011398 A1 Victoria Jane Palmer A1 Wayne Weavell A1 Rosemary Callander A1 Donella Piper A1 Lauralie Richard A1 Lynne Maher A1 Hilary Boyd A1 Helen Herrman A1 John Furler A1 Jane Gunn A1 Rick Iedema A1 Glenn Robert YR 2018 UL http://mh.bmj.com/content/early/2018/07/11/medhum-2017-011398.abstract AB Healthcare systems redesign and service improvement approaches are adopting participatory tools, techniques and mindsets. Participatory methods increasingly used in healthcare improvement coalesce around the concept of coproduction, and related practices of cocreation, codesign and coinnovation. These participatory methods have become the new Zeitgeist—the spirit of our times in quality improvement. The rationale for this new spirit of participation relates to voice and engagement (those with lived experience should be engaged in processes of development, redesign and improvements), empowerment (engagement in codesign and coproduction has positive individual and societal benefits) and advancement (quality of life and other health outcomes and experiences of services for everyone involved should improve as a result). This paper introduces Mental Health Experience Co-design (MH ECO), a peer designed and led adapted form of Experience-based Co-design (EBCD) developed in Australia. MH ECO is said to facilitate empowerment, foster trust, develop autonomy, self-determination and choice for people living with mental illnesses and their carers, including staff at mental health services. Little information exists about the underlying mechanisms of change; the entities, processes and structures that underpin MH ECO and similar EBCD studies. To address this, we identified eight possible mechanisms from an assessment of the activities and outcomes of MH ECO and a review of existing published evaluations. The eight mechanisms, recognition, dialogue, cooperation, accountability, mobilisation, enactment, creativity and attainment, are discussed within an ‘explanatory theoretical model of change’ that details these and ideal relational transitions that might be observed or not with MH ECO or other EBCD studies. We critically appraise the sociocultural and political movement in coproduction and draw on interdisciplinary theories from the humanities—narrative theory, dialogical ethics, cooperative and empowerment theory. The model advances theoretical thinking in coproduction beyond motivations and towards identifying underlying processes and entities that might impact on process and outcome.Trial registration number The Australian and New Zealand Clinical Trials Registry, ACTRN12614000457640 (results).