Funding for this research was provided by:
Helse Vest (911441)
Received: 15 November 2015
Accepted: 29 January 2018
First Online: 23 February 2018
Ethics approval and consent to participate
: The study was approved by the Regional Committee for Medical and Health Research Ethics, Western Norway (ref 2009/3137-CAG) and was conducted at the Neonatal Intensive Care Unit (NICU), Haukeland University Hospital, Bergen, Norway. All patients were included in the study following written informed consent obtained from a parent or guardian after explanation of the study in accordance with the Declaration of Helsinki. The study trial was registered in ExternalRef removed (ExternalRef removed Identifier: NCT01044940).
: Not applicable
: The authors declare that they have no competing interest.
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