Levels of evidence in foot and ankle surgery: progress over the last decade?

Background The focus on evidence-based medicine has led to calls for increased levels of evidence in surgical journals. The purpose of the present study was to review the levels of evidence in articles published in the foot and ankle literature and to assess changes in the level of evidence over a decade. Methods All articles from the years 2000 and 2010 in Foot and Ankle International, Foot and Ankle Surgery, and all foot and ankle articles from JBJS A and JBJS B were analysed. Animal, cadaveric, basic science, editorials, surveys, letters to Editor and correspondence were excluded. Articles were ranked by a five-point level of evidence scale, according to guidelines from the Centre for Evidence Based Medicine. Results A total of 379 articles were analysed from a total of 42 different countries. The kappa value for the inter-observer reliability showed very good agreement between the reviewers for types of evidence (κ = 0.785 (P< 0.01)) and excellent agreement for levels of evidence (κ = 0.846 (P< 0.01)). Between 2000 and 2010 the percentage of high level evidence (Levels I and II) increased (5.2% to 10.3%), and low level evidence (levels III, IV and V) decreased (94.8% to 89.7%) (p=0.09). The most frequent type of study was Therapeutic. The JBJS A produced the highest proportion of high-level evidence. The USA and UK were the highest producer of articles. The number of rest-of-world articles (non USA or UK) increased from 40.5% to 46.4% between 2000 and 2010. Conclusion There has been a trend towards higher levels of evidence in foot and ankle surgery over a decade but the differences did not reach statistical significance