Received: 21 September 2018
Accepted: 28 February 2020
First Online: 30 March 2020
Ethics approval and consent to participate
: This study was approved by the Regional Ethics Committee in Linköping (entry no. 2010/403-31). No patient or patient organization was involved in the planning or execution of the study. Also, limiting the data to information from national registers no patient consent was needed.
: Not applicable.
: The authors declare that they have no competing interests.