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PRISMA Flow Diagram of Study Selection. Adapted from Moher D, Shamseer L, Clarke M, Ghersi D, Liberati A, Petticrew M, Shekelle P; Stewart LA. Preferred Reporting Items for Systematic Review and Meta-An a lysis Protocols (PRISMA-P) 2015 statement. Syst Rev. 2015;4(1):1. doi: 10.1186/2046-4053-4-1.
Abbreviations: AHRQ, Agency for Healthcare Research and Quality; EWS, early warning system; IHI, Institute for Healthcare Improvement.
