title: Current status of evidence-based sports medicine.
abstract: OBJECTIVE
  The purpose of this investigation is to determine the proportion of sports medicine studies that are labeled as Level I Evidence in 5 journals and compare the quality of surgical and nonsurgical studies using simple quality assessment tools (Consolidated Standards of Reporting Trials [CONSORT] and Jadad).
  
  
  METHODS
  By use of PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines over the prior 2 years in the top 5 (citation and impact factor based) sports medicine journals, only Level I Evidence studies were eligible for inclusion and were analyzed. All study types (therapeutic, prognostic, diagnostic, and economic) were analyzed. Study quality was assessed with the level of evidence, Jadad score, and CONSORT 2010 guidelines. Study demographic data were compared among journals and between surgical and nonsurgical studies by use of χ(2), 1-way analysis of variance, and 2-sample Z tests.
  
  
  RESULTS
  We analyzed 190 Level I Evidence studies (10% of eligible studies) (119 randomized controlled trials [RCTs]). Therapeutic, nonsurgical, single-center studies from the United States were the most common studies published. Sixty-two percent of studies reported a financial conflict of interest. The knee was the most common body part studied, and track-and-field/endurance sports were the most common sports analyzed. Significant differences (P < .05) were shown in Jadad and CONSORT scores among the journals reviewed. Overall, the Jadad and CONSORT scores were 2.71 and 77%, respectively. No differences (P > .05) were shown among journals based on the proportion of Level I studies or appropriate randomization. Significant strengths and limitations of RCTs were identified.
  
  
  CONCLUSIONS
  This study showed that Level I Evidence and RCTs comprise 10% and 6% of contemporary sports medicine literature, respectively. Therapeutic, nonsurgical, single-center studies are the most common publications with Level I Evidence. Significant differences across sports medicine journals were found in study quality. Surgical studies appropriately described randomization, blinding, and patient enrollment significantly more than nonsurgical studies.
  
  
  METHODS
  Level I, systematic review of Level I studies.
authors.affiliation: Houston Methodist Hospital, Center for Orthopaedics and Sports Medicine, Houston, Texas, U.S.A.; Division of Sports Medicine, Department of Orthopedic Surgery, Rush Medical College of Rush University, Rush University Medical Center, Chicago, Illinois, U.S.A.. Electronic address: joshuaharrismd@gmail.com.
authors.forename: Joshua D
authors.initials: JD
authors.lastname: Harris
authors.affiliation: Division of Sports Medicine, Department of Orthopedic Surgery, Rush Medical College of Rush University, Rush University Medical Center, Chicago, Illinois, U.S.A.
authors.forename: Gregory
authors.initials: G
authors.lastname: Cvetanovich
authors.affiliation: Division of Sports Medicine, Department of Orthopedic Surgery, Rush Medical College of Rush University, Rush University Medical Center, Chicago, Illinois, U.S.A.
authors.forename: Brandon J
authors.initials: BJ
authors.lastname: Erickson
authors.affiliation: Division of Sports Medicine, Department of Orthopedic Surgery, Rush Medical College of Rush University, Rush University Medical Center, Chicago, Illinois, U.S.A.
authors.forename: Geoffrey D
authors.initials: GD
authors.lastname: Abrams
authors.affiliation: Sports Medicine and Arthroscopy, Toronto Western Hospital, Toronto, Canada; Women's College Hospital, Department of Surgery, University of Toronto, Toronto, Canada.
authors.forename: Jaskarndip
authors.initials: J
authors.lastname: Chahal
authors.affiliation: Division of Sports Medicine, Department of Orthopedic Surgery, Rush Medical College of Rush University, Rush University Medical Center, Chicago, Illinois, U.S.A.
authors.forename: Anil K
authors.initials: AK
authors.lastname: Gupta
authors.affiliation: Division of Sports Medicine, Department of Orthopedic Surgery, Rush Medical College of Rush University, Rush University Medical Center, Chicago, Illinois, U.S.A.
authors.forename: Frank M
authors.initials: FM
authors.lastname: McCormick
authors.affiliation: Division of Sports Medicine, Department of Orthopedic Surgery, Rush Medical College of Rush University, Rush University Medical Center, Chicago, Illinois, U.S.A.
authors.forename: Bernard R
authors.initials: BR
authors.lastname: Bach
mesh_terms: D015706:Bibliometrics; D019317:Evidence-Based Medicine / Q000145:classification / Q000706:statistics & numerical data*; D006801:Humans; D007719:Knee Joint / Q000601:surgery; D010506:Periodicals as Topic / Q000706:statistics & numerical data*; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data; D012107:Research Design / Q000592:standards; D013178:Sports Medicine / Q000592:standards / Q000706:statistics & numerical data*; D014481:United States