Funding for this research was provided by:
Polpharma Scientific Foundation (-)
Received: 23 April 2020
Accepted: 22 December 2020
First Online: 11 January 2021
Ethics approval and consent to participate
: All participants signed informed written consent for participation in the study. The study was approved by the ethics committee in the National Institute of Geriatrics Rheumatology and Rehabilitation, Warsaw, Poland.
: Not applicable.
: The authors declare that they have no competing interests.