title: Levels of Evidence in the Journal of Pediatric Orthopaedics: Update and Comparison to the Journal of Bone and Joint Surgery.
abstract: BACKGROUND
  Periodic review of the published research in pediatric orthopaedics is helpful to evaluate the state of scientific methodology. The purpose of this paper was to review the levels of evidence (LOE) and types of evidence (TOE) published in the Journal of Pediatric Orthopaedics (JPO) from 2009 to 2013 and to compare the percentage of articles with each LOE to pediatric orthopaedic articles published in the Journal of Bone and Joint Surgery-American Volume (JBJS) during the same time.
  
  
  METHODS
  All articles published in JPO from January 1, 2009, to December 31, 2013, were reviewed. Articles were classified as scientific studies, case reports, commentaries/letters to editor, reviews, expert opinion, and basic science articles. All scientific articles in the pediatrics section of the online version of JBJS were reviewed. If listed, the LOE was recorded from all clinical scientific studies. In addition, articles were abstracted for self-reported TOE (therapeutic, diagnostic, prognostic, or economic analysis).
  
  
  RESULTS
  We found 850 citations in JPO over the study period; 646 (76%) were identified as scientific articles and, of those, 552 (85%) had a LOE listed. There were 18 level I articles (3%), 101 level II (18%), 184 level III (34%), and 289 level IV (45%). The TOE was listed in 213 (39%) articles: 114 (54%) therapeutic, 37 (17%) prognostic, 55 diagnostic (26%), and 7 (3%) economic analysis. Comparing 2009 to 2013, the percentage of scientific studies with a self-reported LOE improved significantly (from 81% to 93%, P=0.001). Compared with JPO, JBJS had a significantly higher rate of level I (12% vs. 3%, P=0.006) and a significantly lower rate of level III (23% vs. 34%, P=0.01) articles.
  
  
  CONCLUSIONS
  From 2009 to 2013, 3% of articles in JPO were level I. Significantly more articles are now including a level of evidence designation. Approximately half of published studies are level IV, and most are therapeutic type. A higher percentage of level I studies were published in JBJS during the same time period.
authors.affiliation: University of Tennessee-Campbell Clinic, Memphis, TN.
authors.forename: Robert F
authors.initials: RF
authors.lastname: Murphy
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Cibulas
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Sawyer
authors.forename: David D
authors.initials: DD
authors.lastname: Spence
authors.forename: Derek M
authors.initials: DM
authors.lastname: Kelly
mesh_terms: D035843:Biomedical Research; D002648:Child; D019317:Evidence-Based Medicine; D006801:Humans; D019637:Orthopedic Procedures; D009985:Orthopedics; D010506:Periodicals as Topic / Q000592:standards*