Funding for this research was provided by:
Ministry of Public Health, Doha, Qatar
Received: 20 February 2017
Accepted: 4 April 2018
First Online: 16 April 2018
Ethics approval and consent to participate
: Ethical approval was obtained from the Ministry of Public Health and the Ministry of Development Planning and Statistics, Doha, Qatar. Written consent was obtained from all subjects.
: The authors declare that they have no competing interests.
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