[The meaning of 'consensus' in the context of guidelines--an introduction into the problem].

From the point of view of sociology a consensus may be incompatible with science. This also applies to consensus statements developed by a scientific medical society, since a lack of facts might have been replaced by a majority decision. This is in contrast to the idea of evidence-based medicine (EbM). Personal beliefs do not gain more plausibility (a higher level of evidence) by the mere fact that they are supported by a majority. Thus it is not helpful to demand that EbM-oriented guidelines also be consensus-based.