Funding for this research was provided by:
Fondo Nacional de Desarrollo Científico y Tecnológico (3190058)
Text and Data Mining valid from 2019-12-01
Received: 26 September 2019
Accepted: 16 December 2019
First Online: 26 December 2019
Ethics approval and consent to participate
: The protocol of each wave of the NSH was approved by the Ethics Committee of the Pontificia Universidad Católica de Chile (Pontifical Catholic University of Chile), institution in charge of the studies. Participants signed an informed consent to take part in the study.
: Not applicable.
: The authors declare that they have no competing interests.