Submitted on: 26 November 2010.
Revised on: 21 March 2011.
Accepted on: 13 May 2011.
___________________BMJ Global Health---BMJ PUBLISHING GROUP
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Submitted on: 09 October 2003.
Revised on: 13 January 2004.
Accepted on: 07 February 2004.
___________________BMJ Global Health---BMJ PUBLISHING GROUP
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Submitted on: 28 March 2012.
Revised on: 11 June 2012.
Accepted on: 28 June 2012.
___________________BMJ Global Health---BMJ PUBLISHING GROUP
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Submitted on: 15 May 2013.
Revised on: 17 June 2013.
Accepted on: 03 August 2013.
___________________BMJ Global Health---BMJ PUBLISHING GROUP
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Submitted on: 14 April 2000.
Revised on: 17 May 2000.
Accepted on: 28 May 2000.
___________________BMJ Global Health---BMJ PUBLISHING GROUP