Received: 4 September 2018
Accepted: 20 December 2018
First Online: 7 January 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 and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The study was submitted to the Regional Committee for Medical and Health Research Ethics (REC) as a remit assessment since we were in doubt as to whether our study had to be approved by the REC. The committee concluded that this was a quality improvement study validating register data against source data. The project was in accordance with The Norwegian Health Research Act § 2 and § 4 and was not required for submission and could therefore be implemented and published without the approval of the REC. Written informed consent was obtained from all individual participants included in the study, and on behalf of the minors in this study (under the age of 16) parents have signed a written informed consent. Patients who were minors at the time of inclusion in the register are contacted upon turning 16 and given the option of withdrawing the consent given by their parents, and having the information concerning themselves deleted from the register.
: Not applicable.
: The inter-rater reliability study was performed by an employee of the register. We were aware of this when we designed the study. Therefore, the investigator was blinded to the registrations in the registry during the period the patient records were reviewed.
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