Received: 14 June 2017
Accepted: 22 January 2018
First Online: 9 February 2018
Ethics approval and consent to participate
: The manuscript report data collected from humans. The study was approved by the Saharawi Health Authorities and The Norwegian Regional committees for medical and health research ethics, and was conducted in full accordance with the ethical principles of the World Medical Association Declaration of Helsinki.
: The paper did not contain any individual persons data thus consent for publication was not applicable.
: The authors declare that they have no competing interests.
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