Introduction

Clinical guidelines are rarely based solely on research evidence. In most cases they also incorporate the consensus views of experts. Despite recognition of the need for rigour in developing a consensus, current approaches often lack sufficient transparency, fail to make clear what influence the level of resources in the health system has, lack sufficient reliability, and will never achieve comprehensive and timely coverage of the whole range of health care. We propose a new approach that we believe will be more cost effective and that could meet these challenges.

Need for consensus

Most professional societies and national agencies in North America, Australia, and Europe recognise that guidelines cannot be based on research evidence alone. To paraphrase the philosopher David Hume: “ought” statements such as guidelines cannot be constructed from “is” statements such as research evidence.1 The conversion from is to ought inevitably introduces value judgments about underlying goals and, in this context, somewhat subjective assessments of the quality of the research evidence and its relevance for particular patients and settings.

The recognised need to go beyond the often limited research evidence has led to the use of expert consensus in developing guidelines. The assumption is that the views of a group have greater validity and reliability than the judgment of an individual. In addition, formal or structured methods for developing a consensus have advantages over informal committees: they should offer more transparent ways of synthesising individual judgments, can reduce the influence of dominating personalities and “group think,” and can provide valuable information on the extent and reasons for differences of opinion.2

Since there can be no standard for checking the validity of a consensus based guideline, we …