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Submitted on: 25 July 2013.
Revised on: 15 November 2013.
Accepted on: 03 January 2014.
___________________AMERICAN JOURNAL OF PREVENTIVE MEDICINE
Submitted on: 18 November 2012.
Revised on: 30 December 2012.
Accepted on: 22 February 2013.
___________________AMERICAN JOURNAL OF PREVENTIVE MEDICINE
Submitted on: 20 February 2010.
Revised on: 15 April 2010.
Accepted on: 28 May 2010.
___________________AMERICAN JOURNAL OF PREVENTIVE MEDICINE
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