Orthopaedic surgeons, like all physicians, must make clinical decisions based on the best available evidence. This evidence comes from individual clinical experience and external sources1. Although clinical experience is left to the physician, the medical and surgical literature provides the best external evidence. To facilitate the process of determining the best evidence to answer a clinical question, The Journal of Bone & Joint Surgery assigns level of evidence (LOE) ratings to all clinical articles.

Since 20032, The Journal has used a hierarchical rating system based on the recommendations of the Centre for Evidence-BasedMedicine (CEBM) in Oxford,United Kingdom, to rank articles according to the study design used to answer the primary research question3. In 2011, the CEBM updated its recommendations. After robust internal and external discussion, The Journal has decided to keep pace with the CEBM and has updated our LOE table.