title: Pitfalls in systematic reviews.
abstract: OBJECTIVE
  The term 'evidence-based medicine' means integrating individual clinical expertise with the best available external clinical evidence from systematic research. An important source for those who wish to practise evidence-based medicine is the systematic review. Systematic reviews, however, are not without their pitfalls. This review will consider the problems and challenges for researchers and users of systematic reviews.
  
  
  RESULTS
  Failure to adequately assess study quality, funding bias, publication bias, reliance on outcomes that provide no help in clinical decision-making, analysis errors and the incorrect use of evidence statements are all common pitfalls in systematic reviews.
  
  
  CONCLUSIONS
  There are several steps in completing a systematic review. These include developing the clinical question, searching for all available literature, study selection, assessment of study quality, data extraction, data analysis, interpreting the results, implications for practice and further research, and finally updating the review in a timely manner. Authors of systematic reviews need to be aware of these problems and attempt to address them so that research evidence may be of clinical value to both providers and consumers of healthcare.
authors.affiliation: Cochrane Menstrual Disorders and Subfertility Group, Department of Obstetrics and Gynaecology, University of Auckland, Auckland, New Zealand. c.farquhar@auckland.ac.nz
authors.forename: Cynthia
authors.initials: C
authors.lastname: Farquhar
authors.forename: Andy
authors.initials: A
authors.lastname: Vail
mesh_terms: D019317:Evidence-Based Medicine; D006801:Humans; D012196:Review Literature as Topic