Submitted on: 08 July 2013.
Revised on: 17 September 2013.
Accepted on: 11 November 2013.
___________________AMERICAN JOURNAL OF PUBLIC HEALTH
Submitted on: 21 August 2012.
Revised on: 15 December 2012.
Accepted on: 29 December 2012.
___________________AMERICAN JOURNAL OF PUBLIC HEALTH
Submitted on: 19 May 2006.
Revised on: 25 July 2006.
Accepted on: 02 September 2006.
___________________AMERICAN JOURNAL OF PUBLIC HEALTH
Submitted on: 27 October 2019.
Revised on: 12 February 2020.
Accepted on: 09 April 2020.
___________________AMERICAN JOURNAL OF PUBLIC HEALTH
Submitted on: 16 September 2010.
Revised on: 23 November 2010.
Accepted on: 05 December 2010.
___________________AMERICAN JOURNAL OF PUBLIC HEALTH
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