Ziegelmann, Matthew J.
Farrell, Michael Ryan
Levine, Laurence A.
Article History
Received: 5 March 2019
Accepted: 25 April 2019
First Online: 11 May 2019
Compliance with ethical standards
:
: The authors declare that they have no relevant conflicts of interest.
: Although retrospective studies are conducted on already available data or biological material (for which formal consent may not be needed or is difficult to obtain) ethical approval may be required dependent on the law and the national ethical guidelines of a country. Authors should check with their institution to make sure they are complying with the specific requirements of their country.
: Informed consent was obtained from all individual participants included in the study.