Funding for this research was provided by:
Universidad de La Frontera (DFP16-0012)
Text and Data Mining valid from 2019-08-10
Received: 1 July 2019
Accepted: 5 August 2019
First Online: 10 August 2019
Compliance with ethical standards
: The authors declare that they have no conflict of interest.
: This study was approved by the Scientific Ethics Committee of Universidad de La Frontera (Decision N°084/17 of 9 August 2017).