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Article History

Received: 6 January 2018

Accepted: 19 December 2018

First Online: 7 January 2019

Ethics approval and consent to participate

: The Central Denmark Region Committees on Biomedical Research Ethics on the 7th may 2009 (ref: M-20090050), and qualified for registration in the International Standard Randomised Controlled Trial Number Registry (NCT01015716 - Prospectively registered). Informed consent was obtained from all informants both verbally and in writing and they were assured anonymity and confidentiality.

: Not applicable

: The authors declare that they have no competing interests.

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