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Article History

Received: 20 August 2018

Accepted: 8 April 2019

First Online: 2 May 2019

Ethics approval and consent to participate

: Ethics approval was granted by the Medical Science Inter-Divisional Research Ethics Committee of the University of Oxford, UK, reference number R36311_RE001. Consent to participate was implied by return of the anonymous completed postal survey, and such approach was ratified by the above Ethics Committee.

: Not applicable.

: The authors declare that they have no competing interests.

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