[Representation and representativeness in health councils: between formalization and participatory legitimacy].

The action of social representatives greatly influences the performance of health councils and the quality of participatory management in the Brazilian Unified National Health System. This study aimed to analyze the mechanisms of representation and forms of representativeness within health councils in municipalities of different population sizes. This multiple case study was carried out in Vitória da Conquista, Guanambi, and Urandi, in Bahia State, Brazil.