Funding for this research was provided by:
Universitetet i Bergen
Article History
Received: 6 September 2017
Accepted: 13 June 2018
First Online: 20 June 2018
Ethics approval and consent to participate
: The survey protocol was approved by the National Ethical Clearance Committee of the Federal Ministry of Health in Khartoum, Sudan. A written informed consent was obtained from interviewed respondents.
: Not applicable.
: The authors declare that they have no competing interests.
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