Text and Data Mining valid from 2019-04-02
Received: 21 December 2018
Revised: 7 March 2019
Accepted: 13 March 2019
First Online: 2 April 2019
Compliance with ethical standards
: The authors declare that they have no conflict of interest.
: The study was approved by Clinical Research Ethics Committees at the hospitals involved and performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments.
: Informed consent was obtained from all individual participants included in the study.