Submitted on: 04 October 2013.
Revised on: 26 December 2013.
Accepted on: 11 January 2014.
___________________BMC PUBLIC HEALTH---BMC
Submitted on: 30 September 2002.
Revised on: 05 January 2003.
Accepted on: 10 February 2003.
___________________BMC PUBLIC HEALTH---BMC
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Submitted on: 26 August 2023.
Revised on: 24 September 2023.
Accepted on: 06 November 2023.
___________________BMC PUBLIC HEALTH---BMC
Submitted on: 16 August 2013.
Revised on: 04 October 2013.
Accepted on: 26 October 2013.
___________________BMC PUBLIC HEALTH---BMC
Submitted on: 29 January 2007.
Revised on: 06 May 2007.
Accepted on: 21 June 2007.
___________________BMC PUBLIC HEALTH---BMC
Submitted on: 24 February 2011.
Revised on: 02 June 2011.
Accepted on: 29 June 2011.
___________________BMC PUBLIC HEALTH---BMC
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Submitted on: 21 January 2012.
Revised on: 15 May 2012.
Accepted on: 17 June 2012.
___________________BMC PUBLIC HEALTH---BMC