Levels of evidence in hand surgery: a review and guide

This article explores the background to the concept of levels of evidence and their role in promoting the principles of evidence-based medicine within hand surgery. The Journal of Hand Surgery (European Volume) requires allocation of a level of evidence to each full-length clinical research article. The system employed by the Journal is described, together with discussion of limitations and difficulties in application. Most articles published on hand surgery still have a low level of evidence. Insights and editorial perspectives on various types of research study and the classification of evidence levels are included. Clinical importance of articles and the need to encourage innovation as opposed to high levels of evidence are also discussed.