Funding for this research was provided by:
Sophies Minde AS, Oslo, Norway (06/2014)
Norwegian Orthopaedic Association/Heraeus Medical
Received: 2 October 2018
Accepted: 16 May 2019
First Online: 24 May 2019
Ethics approval and consent to participate
: The study was evaluated by the Regional Ethics Committee South East and was deemed to not require approval (reference number 2015/409). Data was collected and handled in accordance with requirements from the local data protection officer. The study was exempt from consent to participate. The Norwegian Data Inspectorate has approved the registration of data in the NHFR.
: Not applicable.
: The authors declare that they have no competing interests.
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