- Correspondence to Dr Daren K Heyland, Medicine and Community Health and Epidemiology, Queen's University, Kingston General Hospital, Angada 4, 76 Stuart St, Kingston, ON, Canada K7L 2V7;
- Received 7 July 2015
- Revised 18 September 2015
- Accepted 13 October 2015
- Published online 17 August 2016.
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- Data supplement 1 - Online supplement
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