Clinical practice guidelines: from methodological to practical issues.

The main goal of clinical practice guidelines is to help clinical decision by practitioners, who can not integrate in their daily practice all the published data concerning new technologies and knowledge. Guidelines also have growing applications in the ethical, legal, socio-economic, public policy and health care funding fields. This article describes the various methodologies that have been proposed to develop guidelines. These methods rely to varying degrees on formal methods of analysis of scientific evidence and expert opinions. Then a step by step process is described, that should ensure a rigorous, feasible and explicit guideline development and lead to valid and applicable recommendations. In order for guidelines to be used, they have to be efficiently implemented. Respective efficiency and justification of educational and coercive methods of implementation are discussed.