title: Risk of bias and methodological appraisal practices in systematic reviews published in anaesthetic journals: a meta-epidemiological study.
abstract: The validity of primary study results included in systematic reviews plays an important role in drawing conclusions about intervention effectiveness and carries implications for clinical decision-making. We evaluated the prevalence of methodological quality and risk of bias assessments in systematic reviews published in the five highest-ranked anaesthesia journals since 2007. The initial PubMed search yielded 315 citations, and our final sample after screening consisted of 207 systematic reviews. One hundred and seventy-four reviews conducted methodological quality/risk of bias analyses. The Jadad scale was most frequently used. Forty-four of the 83 reviews that included high risk of bias studies re-analysed their data omitting these trials: 20 showed differences in pooled effect estimates. Reviews containing a greater number of primary studies evaluated quality less frequently than smaller reviews. Overall, the majority of reviews evaluated bias; however, many applied questionable methods. Given the potential effects of bias on summary outcomes, greater attention is warranted.
authors.affiliation: Institutional Research and Analytics, Oklahoma State University Center for Health Sciences, Tulsa, Oklahoma, USA.
authors.forename: B N
authors.initials: BN
authors.lastname: Detweiler
authors.affiliation: Institutional Research and Analytics, Oklahoma State University Center for Health Sciences, Tulsa, Oklahoma, USA.
authors.forename: L E
authors.initials: LE
authors.lastname: Kollmorgen
authors.affiliation: Institutional Research and Analytics, Oklahoma State University Center for Health Sciences, Tulsa, Oklahoma, USA.
authors.forename: B A
authors.initials: BA
authors.lastname: Umberham
authors.affiliation: Institutional Research and Analytics, Oklahoma State University Center for Health Sciences, Tulsa, Oklahoma, USA.
authors.forename: R J
authors.initials: RJ
authors.lastname: Hedin
authors.affiliation: Institutional Research and Analytics, Oklahoma State University Center for Health Sciences, Tulsa, Oklahoma, USA.
authors.forename: B M
authors.initials: BM
authors.lastname: Vassar
mesh_terms: D000776:Anesthesiology; D015982:Bias; D016021:Epidemiologic Studies; D006801:Humans; D010506:Periodicals as Topic; D012196:Review Literature as Topic; D012306:Risk
keywords: cochrane; meta-analysis; research quality; risk of bias; systematic review