1. Heterogeneity of studies in anesthesiology systematic reviews: a meta-epidemiological review and proposal for evidence mapping 
B. Umberham, R. Hedin, B. Detweiler, L. Kollmorgen, C. Hicks, M. Vassar 
British Journal of Anaesthesia 
Volume 119, Issue 5, Pages (November 2017)
DOI: /bja/aex251
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2. Fig 1 PRISMA flowchart of excluded articles.
British Journal of Anaesthesia  , DOI: ( /bja/aex251)
Copyright © 2017 The Author(s) Terms and Conditions

3. Fig 2 Evidence mapping flow chart.
British Journal of Anaesthesia  , DOI: ( /bja/aex251)
Copyright © 2017 The Author(s) Terms and Conditions