Article History
Received: 18 January 2018
Accepted: 16 May 2018
First Online: 29 May 2018
Ethics approval and consent to participate
: Ethics approval and consent to participate is not applicable to this study.
: SL Norris is an employee of the World Health Organization (WHO) where she oversees the guideline quality assurance process and guideline methods development. She is also an active member of the GRADE Working Group.Zhicheng Wang and Lisa Bero declare that they have no competing interests.
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