Received: 7 May 2020
Accepted: 15 July 2020
First Online: 23 July 2020
Ethics approval and consent to participate
: This was a retrospective analysis of data obtained over a 19-year period. The data were collected anonymously to ensure impartial analysis; therefore, written informed consent was not obtained from the individual participants. The research was approved by the La Paz–Carlos III Hospital’s Ethics Committee.
: Not applicable.
: All authors declare no potential conflicts of interest and no sources of support.