Submitted on: 28 August 2017.
Revised on: 07 December 2017.
Accepted on: 03 February 2018.
___________________Journal of Epidemiology and Global Health
Submitted on: 06 January 2015.
Revised on: 13 March 2015.
Accepted on: 08 May 2015.
___________________Journal of Epidemiology and Global Health
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Submitted on: 23 March 2005.
Revised on: 04 May 2005.
Accepted on: 14 May 2005.
___________________Journal of Epidemiology and Global Health
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