Submitted on: 04 September 2002.
Revised on: 17 October 2002.
Accepted on: 14 November 2002.
___________________Frontiers in Emergency Medicine
Submitted on: 05 January 2004.
Revised on: 19 April 2004.
Accepted on: 11 May 2004.
___________________Frontiers in Emergency Medicine
Submitted on: 19 August 2012.
Revised on: 22 November 2012.
Accepted on: 19 December 2012.
___________________Frontiers in Emergency Medicine
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