Submitted on: 08 August 1999.
Revised on: 04 October 1999.
Accepted on: 30 November 1999.
___________________INJURY PREVENTION---BMJ PUBLISHING GROUP
Submitted on: 24 August 2010.
Revised on: 18 December 2010.
Accepted on: 27 January 2011.
___________________INJURY PREVENTION---BMJ PUBLISHING GROUP
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http://reply.papertrans.cn/2/127/12631/12631-24.png
Submitted on: 31 March 2020.
Revised on: 17 June 2020.
Accepted on: 07 July 2020.
___________________INJURY PREVENTION---BMJ PUBLISHING GROUP
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Submitted on: 09 May 2021.
Revised on: 05 September 2021.
Accepted on: 28 September 2021.
___________________INJURY PREVENTION---BMJ PUBLISHING GROUP
Submitted on: 08 September 2000.
Revised on: 17 November 2000.
Accepted on: 02 January 2001.
___________________INJURY PREVENTION---BMJ PUBLISHING GROUP
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Submitted on: 02 January 2017.
Revised on: 24 April 2017.
Accepted on: 13 May 2017.
___________________INJURY PREVENTION---BMJ PUBLISHING GROUP