Funding for this research was provided by:
Yrjö Jahnssonin Säätiö
Finnish Ministry of Education and Culture
Text and Data Mining valid from 2019-03-25
Received: 19 June 2018
Accepted: 18 March 2019
First Online: 25 March 2019
Ethics approval and consent to participate
: The study was approved by the ethics committee of Northern Ostrobothnia Hospital District, Finland.
: The authors declare that they have no competing interests.
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