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Article History

Received: 26 July 2018

Accepted: 12 October 2018

First Online: 19 October 2018

Ethics approval and consent to participate

: All the procedures performed in this study were in accordance with the ethical standards of the Helsinki Declaration and the study was approved by the central ethical review board, Gothenburg, Sweden, Dnr: 970–15.

: Not applicable

: The authors declare that they have no competing interests.

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