Submitted on: 26 June 2022.
Revised on: 10 August 2022.
Accepted on: 19 September 2022.
___________________Gaceta Sanitaria---ELSEVIER
Submitted on: 25 May 2020.
Revised on: 19 September 2020.
Accepted on: 18 October 2020.
___________________Gaceta Sanitaria---ELSEVIER
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Submitted on: 27 May 2004.
Revised on: 26 June 2004.
Accepted on: 16 August 2004.
___________________Gaceta Sanitaria---ELSEVIER
Submitted on: 17 January 2011.
Revised on: 24 March 2011.
Accepted on: 20 April 2011.
___________________Gaceta Sanitaria---ELSEVIER
Submitted on: 30 August 2007.
Revised on: 13 December 2007.
Accepted on: 18 January 2008.
___________________Gaceta Sanitaria---ELSEVIER
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