Received: 16 October 2017
Accepted: 8 February 2018
First Online: 21 February 2018
Ethics approval and consent to participate
: Ethical approval was sought from the School of Healthcare Sciences Research Ethics Committee, Cardiff University, Cardiff, UK, and King Abdullah International Medical Research Centre, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia.
: Consent for publication was obtained from parents or legal guardians of patients.
: The authors declare that they have no competing interests.
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