Submitted on: 08 December 2001.
Revised on: 25 March 2002.
Accepted on: 04 April 2002.
___________________International Journal of Preventive Medicine
Submitted on: 27 January 2000.
Revised on: 03 April 2000.
Accepted on: 01 June 2000.
___________________International Journal of Preventive Medicine
Submitted on: 10 December 2005.
Revised on: 16 March 2006.
Accepted on: 14 April 2006.
___________________International Journal of Preventive Medicine
Submitted on: 21 February 2011.
Revised on: 14 May 2011.
Accepted on: 09 June 2011.
___________________International Journal of Preventive Medicine
Submitted on: 25 May 2008.
Revised on: 08 July 2008.
Accepted on: 20 August 2008.
___________________International Journal of Preventive Medicine
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