MacOrtho is pleased to congratulate Dr. Nathan Evaniew for receiving the Resident’s Best Paper Award at the 15th Annual Scientific Conference of the Canadian Spine Society in Halifax last week. Dr. Evaniew presented 'Strategies to improve the credibility of meta-analyses in spine surgery: A systematic survey’.
Authors: Nathan Evaniew, Leon van der Watt, Mohit Bhandari, Michelle Ghert, Ilyas Aleem, Brian Drew, Gordon Guyatt
OBJECTIVES: Meta-analyses are powerful tools that can synthesize existing research and support evidence- based care. They have become increasingly popular in spine surgery, but the rigor with which they are being conducted has not been evaluated. Our objectives were to evaluate the methodological credibility of spine surgery meta-analyses and to propose strategies to improve future research.
METHODS: We conducted a systematic survey of spine surgery meta-analyses published since 1990. Two reviewers independently evaluated credibility according to the Users’ Guide to the Medical Literature and completeness of reporting according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. We used multivariable linear regression to evaluate potential associations. Inter-rater agreement was quantified using kappa and intra-class correlation (ICC) coefficients
RESULTS: We identified 132 eligible meta-analyses. The mean credibility score was 3 out of 7 (SD 1.4; ICC 0.86). Clinical questions were judged as sensible in 125 (95%), searches were exhaustive in 102 (77%), and risk of bias assessments were undertaken in 91 (69%). Seven (5%) meta- analyses addressed possible explanations for heterogeneity using a priori subgroup hypotheses and 24 (18%) presented results that were immediately clinically applicable. Investigators undertook duplicate assessments of eligibility, risk of bias, and data extraction in 46 (35%), and rated overall confidence in the evidence in 24 (18%). Later publication year, increasing Journal Impact Factor, increasing number of databases, inclusion of RCTs, and inclusion of non-English studies were associated with higher credibility (p<0.05). The mean score for reporting was 18 out of 27 (SD 4.4; ICC 0.94).
CONCLUSIONS: The credibility of many current spine surgery meta-analyses is limited. Researchers can improve future meta-analyses by performing exhaustive literature searches, addressing possible explanations of heterogeneity, presenting results in a clinically useful manner, reproducibly selecting and assessing primary studies, addressing confidence in the pooled effect estimates, and adhering to guidelines for complete reporting.