[Challenges for developing a comparative analytical model for health services].

This paper presents different models that describe health determinants, services, and systems. It highlights the important model developed by Contandriopoulos, proposing a separation between the health status and health care circuits. The article is intended as a contribution to the field of comparative analysis with a new theoretical, methodological, and evaluative approach. Problems were identified in the development of a new model. Decentralization and access are introduced as categories, suggesting that they may take part in such new model.