Received: 16 February 2018
Accepted: 12 March 2018
First Online: 2 April 2018
Ethics approval and consent to participate
: All women invited to participate in the ABC study were given written information explaining the purpose of the study and they were informed that participation was voluntary. Written informed consent was obtained from all participants. The study was approved by the Regional Committee for Ethics in Medical Research in Norway (Approval No. S-08013a). All data were anonymous.
: The authors declare that they have no competing interest related to the work presented.
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