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Submitted on: 06 June 2007.
Revised on: 09 August 2007.
Accepted on: 09 September 2007.
___________________AMERICAN JOURNAL OF PUBLIC HEALTH
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Submitted on: 10 June 2023.
Revised on: 03 September 2023.
Accepted on: 10 October 2023.
___________________AMERICAN JOURNAL OF PUBLIC HEALTH
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Submitted on: 20 August 2016.
Revised on: 30 September 2016.
Accepted on: 14 October 2016.
___________________AMERICAN JOURNAL OF PUBLIC HEALTH
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