Submitted on: 11 February 2002.
Revised on: 17 May 2002.
Accepted on: 08 June 2002.
___________________Journal of Adolescent Health---ELSEVIER SCIENCE INC
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Submitted on: 08 October 2011.
Revised on: 09 December 2011.
Accepted on: 28 December 2011.
___________________Journal of Adolescent Health---ELSEVIER SCIENCE INC
Submitted on: 30 March 2004.
Revised on: 27 May 2004.
Accepted on: 12 June 2004.
___________________Journal of Adolescent Health---ELSEVIER SCIENCE INC
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Submitted on: 10 September 2002.
Revised on: 10 October 2002.
Accepted on: 11 November 2002.
___________________Journal of Adolescent Health---ELSEVIER SCIENCE INC
Submitted on: 09 April 2003.
Revised on: 23 June 2003.
Accepted on: 21 August 2003.
___________________Journal of Adolescent Health---ELSEVIER SCIENCE INC