Submitted on: 25 July 2004.
Revised on: 15 November 2004.
Accepted on: 11 January 2005.
___________________JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
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Submitted on: 04 December 1998.
Revised on: 19 March 1999.
Accepted on: 13 May 1999.
___________________JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
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