Ethical considerations
This study was performed in accordance with the Declaration of Helsinki ethical principles for medical research and was approved by the Regional Ethics Review board in Linköping, Sweden (Dnr: M119-08, 2010/101 − 32, 2012/416 − 31, 2018/330 − 31). All participants received written information and provided written informed consent to participate prior to analyzing data. Data was anonymized and stored in a secure locker, and as encrypted computer files at Linköping University.