Funding for this research was provided by:
State of Kuwait (PhD Studentship)
Received: 28 February 2018
Accepted: 22 May 2018
First Online: 31 May 2018
Ethics approval and consent to participate
: This study was approved by the NHS National Research Ethics Service in the United Kingdom under ethics approval 10/H1304/13 and was conducted in accordance with the Declaration of Helsinki. All participants provided informed written consent prior to the study.
: The authors declare that they have no competing interests.
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