Funding for this research was provided by:
Region Östergotland (LIO-620341)
Linköpings Universitet (LIO-697941)
LFoU grant Region Östergötland
Received: 16 April 2019
Accepted: 29 July 2019
First Online: 9 August 2019
Ethics approval and consent to participate
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional research committee (Linköping University) and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Our regional Ethical Review Board (EPN, Linköping) approved this retrospective study, and the requirement for informed consent was waived.
: Not applicable.
: The authors declare that they have no competing interests.