Submitted on: 21 February 2020.
Revised on: 05 April 2020.
Accepted on: 21 May 2020.
___________________BMC Geriatrics---BMC
Submitted on: 18 December 2011.
Revised on: 26 February 2012.
Accepted on: 22 March 2012.
___________________BMC Geriatrics---BMC
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Submitted on: 23 July 2018.
Revised on: 01 October 2018.
Accepted on: 18 November 2018.
___________________BMC Geriatrics---BMC
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Submitted on: 27 February 2003.
Revised on: 11 May 2003.
Accepted on: 07 July 2003.
___________________BMC Geriatrics---BMC
Submitted on: 04 May 2018.
Revised on: 22 August 2018.
Accepted on: 07 September 2018.
___________________BMC Geriatrics---BMC
Submitted on: 20 June 2002.
Revised on: 05 October 2002.
Accepted on: 28 October 2002.
___________________BMC Geriatrics---BMC
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