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Submitted on: 29 January 2002.
Revised on: 23 February 2002.
Accepted on: 24 March 2002.
___________________Family Medicine and Primary Care Review
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Submitted on: 31 March 1998.
Revised on: 26 April 1998.
Accepted on: 08 May 1998.
___________________Family Medicine and Primary Care Review
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Submitted on: 24 March 2007.
Revised on: 19 April 2007.
Accepted on: 10 May 2007.
___________________Family Medicine and Primary Care Review
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