Funding for this research was provided by:
Text and Data Mining valid from 2020-01-22
Received: 28 April 2019
Accepted: 7 January 2020
First Online: 22 January 2020
Ethics approval and consent to participate
: Research was performed in accordance with the Declaration of Helsinki and was approved by an appropriate ethics committee.Informed consent to participate in the study was obtained from participants (or their parent, in the case of children under 16).
: Not applicable.
: The authors declare that they have no competing interests.