[Lay expertise in patient organizations: an instrument for health democracy].

In the health sector, lay expertise refers to two distinct but related phenomena: experiential expertise, i.e. expertise based on the experience of a specific condition, and medical-scientific expertise. A significant part of the activities of patient organizations are devoted to developing both forms of expertise: on the one hand, they collect, shape, analyze their members' testimonies, conduct surveys and produce statistics; on the other hand, they provide a scientific watch, synthesize the academic literature, publish documents for the public or organize conferences. This two-fold expertise is mobilized in actions directed both at empowering of the individual patient as well as at shaping health policies: therefore it contributes to health democracy, understood in the double sense used in the March 4th 2002 Act, i.e. as participation of individuals to decisions regarding their own health and as participation of patients' and users' representatives to the governance of health.