title: Quality of reporting in systematic reviews of adverse events: systematic review.
abstract: OBJECTIVE
  To examine the quality of reporting of harms in systematic reviews, and to determine the need for a reporting guideline specific for reviews of harms.
  
  
  METHODS
  Systematic review.
  
  
  METHODS
  Cochrane Database of Systematic Reviews (CDSR) and Database of Abstracts of Reviews of Effects (DARE).
  
  
  METHODS
  Databases were searched for systematic reviews having an adverse event as the main outcome, published from January 2008 to April 2011. Adverse events included an adverse reaction, harms, or complications associated with any healthcare intervention. Articles with a primary aim to investigate the complete safety profile of an intervention were also included. We developed a list of 37 items to measure the quality of reporting on harms in each review; data were collected as dichotomous outcomes ("yes" or "no" for each item).
  
  
  RESULTS
  Of 4644 reviews identified, 309 were systematic reviews or meta-analyses primarily assessing harms (13 from CDSR; 296 from DARE). Despite a short time interval, the comparison between the years of 2008 and 2010-11 showed no difference on the quality of reporting over time (P=0.079). Titles in fewer than half the reviews (proportion of reviews 0.46 (95% confidence interval 0.40 to 0.52)) did not mention any harm related terms. Almost one third of DARE reviews (0.26 (0.22 to 0.31)) did not clearly define the adverse events reviewed, nor did they specify the study designs selected for inclusion in their methods section. Almost half of reviews (n=170) did not consider patient risk factors or length of follow-up when reviewing harms of an intervention. Of 67 reviews of complications related to surgery or other procedures, only four (0.05 (0.01 to 0.14)) reported professional qualifications of the individuals involved. The overall, unweighted, proportion of reviews with good reporting was 0.56 (0.55 to 0.57); corresponding proportions were 0.55 (0.53 to 0.57) in 2008, 0.55 (0.54 to 0.57) in 2009, and 0.57 (0.55 to 0.58) in 2010-11.
  
  
  CONCLUSIONS
  Systematic reviews compound the poor reporting of harms data in primary studies by failing to report on harms or doing so inadequately. Improving reporting of adverse events in systematic reviews is an important step towards a balanced assessment of an intervention.
authors.affiliation: Department of Pediatrics, 4-548 Edmonton Clinic Health Academy, University of Alberta, Edmonton, Canada.
authors.forename: Liliane
authors.initials: L
authors.lastname: Zorzela
authors.forename: Su
authors.initials: S
authors.lastname: Golder
authors.forename: Yali
authors.initials: Y
authors.lastname: Liu
authors.forename: Karen
authors.initials: K
authors.lastname: Pilkington
authors.forename: Lisa
authors.initials: L
authors.lastname: Hartling
authors.forename: Ari
authors.initials: A
authors.lastname: Joffe
authors.forename: Yoon
authors.initials: Y
authors.lastname: Loke
authors.forename: Sunita
authors.initials: S
authors.lastname: Vohra
mesh_terms: D057189:Checklist; D006801:Humans; D015201:Meta-Analysis as Topic; D016032:Randomized Controlled Trials as Topic / Q000009:adverse effects* / Q000379:methods; D012107:Research Design / Q000592:standards*; D012196:Review Literature as Topic