Funding for this research was provided by:
Text and Data Mining valid from 2019-04-22
First Online: 22 April 2019
Compliance with Ethical Standards
: Because this was a retrospective study of patients’ clinical records, a waiver was obtained for Human Study IRB approval. This study has been performed in accordance with the ethical standards as laid down in the 1964 Declaration of Helsinki and its later amendments. For this type of study, formal consent is not required.