title: Update on the Methodological Quality of Research Published in The American Journal of Sports Medicine: Comparing 2011-2013 to 10 and 20 Years Prior.
abstract: In recent years, the number of articles in The American Journal of Sports Medicine (AJSM) has risen dramatically, with an increasing emphasis on evidence-based medicine in orthopaedics and sports medicine.
  
  
  
  Despite the increase in the number of articles published in AJSM over the past decade, the methodological quality of articles in 2011-2013 has improved relative to those in 2001-2003 and 1991-1993.
  
  
  
  Meta-analysis.
  
  
  
  All articles published in AJSM during 2011-2013 were reviewed and classified by study design. For each article, the use of pertinent methodologies, such as prospective data collection, randomization, control groups, and blinding, was recorded. The frequency of each article type and the use of evidence-based techniques were compared relative to 1991-1993 and 2001-2003 by use of Pearson χ(2) testing.
  
  
  
  The number of research articles published in AJSM more than doubled from 402 in 1991-1993 and 423 in 2001-2003 to 953 in 2011-2013. Case reports decreased from 15.2% to 10.6% to 2.1% of articles published over the study period (P < .001). Cadaveric/human studies and meta-analysis/literature review studies increased from 5.7% to 7.1% to 12.4% (P < .001) and from 0.2% to 0.9% to 2.3% (P = .01), respectively. Randomized, prospective clinical trials increased from 2.7% to 5.9% to 7.4% (P = .007). Fewer studies used retrospective compared with prospective data collection (P < .001). More studies tested an explicit hypothesis (P < .001) and used controls (P < .001), randomization (P < .001), and blinding of those assessing outcomes (P < .001). Multi-investigator trials increased (P < .001), as did the proportion of articles citing a funding source (P < .001).
  
  
  
  Despite a dramatic increase in the number of published articles, the research published in AJSM shifted toward more prospective, randomized, controlled, and blinded designs during 2011-2013 compared with 2001-2003 and 1991-1993, demonstrating a continued improvement in methodological quality.
authors.affiliation: Washington University, St Louis, Missouri, USA brophyr@wudosis.wustl.edu.
authors.forename: Robert H
authors.initials: RH
authors.lastname: Brophy
authors.affiliation: Washington University, St Louis, Missouri, USA.
authors.forename: Dylan
authors.initials: D
authors.lastname: Kluck
authors.affiliation: Hospital for Special Surgery, New York, New York, USA.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Marx
mesh_terms: D019317:Evidence-Based Medicine / Q000379:methods* / Q000706:statistics & numerical data; D006801:Humans; D009985:Orthopedics / Q000379:methods* / Q000706:statistics & numerical data; D010506:Periodicals as Topic / Q000706:statistics & numerical data*; D012107:Research Design / Q000706:statistics & numerical data; D013178:Sports Medicine / Q000379:methods* / Q000706:statistics & numerical data
keywords: collaborative research; evidence-based medicine; evidence-based surgery; multicenter studies; research methodology; sports medicine