Systematic reviews: CRD's guidance for undertaking reviews in health care

Systematic reviews and meta-analyses are assuming greater importance in influencing policy makers and clinical opinion worldwide. However, the increasing use and sometimes abuse of these analyses has caused many health-care workers to become sceptical about their benefits. Easy methods to weigh and understand the available evidence are indeed essential for readers and reviewers. The third updated and expanded edition of Systematic Reviews by the Centre for Reviews and Dissemination, a part of the National Institute for Health Research (University of York, UK) is an easy to follow guide that provides researchers with practical suggestions on doing systematic reviews and meta-analyses, from getting started to the final dissemination of the results.