Received: 28 February 2020
Accepted: 25 March 2020
First Online: 21 April 2020
Compliance with ethical standards
: The scientific guarantor of this publication is Philippe Autier.
: The authors of this manuscript declare no relationships with any companies whose products or services may be related to the subject matter of the article.
: One of the authors, Philippe Autier, has significant statistical expertise.
: Written informed consent was not required for this study because based on published data.
: Institutional Review Board approval was not required because no human subjects or animals involved.
: • Not applicable.
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