Submitted on: 03 May 2004.
Revised on: 27 August 2004.
Accepted on: 01 October 2004.
___________________JMIR Public Health and Surveillance
Submitted on: 21 June 1999.
Revised on: 19 September 1999.
Accepted on: 22 October 1999.
___________________JMIR Public Health and Surveillance
Submitted on: 18 July 2021.
Revised on: 18 September 2021.
Accepted on: 18 October 2021.
___________________JMIR Public Health and Surveillance
Submitted on: 05 October 2021.
Revised on: 24 January 2022.
Accepted on: 05 February 2022.
___________________JMIR Public Health and Surveillance
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