title: Levels of evidence in plastic surgery research over 20 years.
abstract: BACKGROUND
  Evidence-based medicine, particularly randomized controlled trials, influences many daily decisions within the medical specialties. The structure of questions asked during the history and selection of physical examination maneuvers, diagnostic tests, and treatment regimens are all guided by evidence-based medicine. Implementation of evidence-based medicine has been slower in surgical practice. The purpose of this study was to survey published plastic surgery literature to evaluate changes in the level of evidence from pre-evidence-based medicine popularization to the present time.
  
  
  METHODS
  Articles from Plastic and Reconstructive Surgery for the years 1983, 1993, and 2003 were ranked by a five-point level of evidence scale. The highest level of evidence value (1) was given to randomized clinical trials and the lowest value (5) was given to individual case reports; 989 articles were ranked.
  
  
  RESULTS
  The average level of evidence of an article published in 1983 was lower than that of one published in 2003 (4.42 versus 4.16, respectively), and the majority of research (86.9 percent in 2003) remained largely uncontrolled and descriptive in nature. However, there was a trend toward higher-quality research. The percentage of studies with control or placebo groups nearly doubled from 1983 to 2003 (from 7.21 percent to 13.7 percent), and the number of randomized clinical trials increased (zero versus seven).
  
  
  CONCLUSIONS
  The plastic surgery literature has responded to the demand for more evidence-based medicine, but the rate of change has been slow and the field will likely never enjoy the high level of evidence of medical fields.
authors: Calgary, Alberta, Canada From the Division of Plastic Surgery, Department of Surgery, Faculty of Medicine, University of Calgary.
authors: Frederick
authors: F
authors: Loiselle
authors: Raman C
authors: RC
authors: Mahabir
authors: A Robert
authors: AR
authors: Harrop
mesh_terms: D035843:Biomedical Research / Q000592:standards*; D019317:Evidence-Based Medicine; D019651:Plastic Surgery Procedures; D013997:Time Factors