Text and Data Mining valid from 2019-04-09
Received: 6 November 2018
Accepted: 25 March 2019
First Online: 9 April 2019
Compliance with ethical standards
: All participants provided signed informed consent according to the Declaration of Helsinki. The study was approved by the ethics committee of the Regional Administration of Health of Lisbon, Portugal (Proc.063/CES/INV/201).