- Correspondence to Dr Alyshah Abdul Sultan, Division of Epidemiology and Public Health, City Hospital campus, The University of Nottingham, Room B121, Clinical Science Building 2, Hucknall Road, Nottingham, NG5 1PB, UK;
- Received 19 August 2014
- Revised 1 October 2014
- Accepted 2 October 2014
- Published online 24 October 2014.
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