Received: 2 January 2020
Accepted: 4 February 2020
First Online: 21 February 2020
Ethics approval and consent to participate
: The study was conducted in agreement with the ethical standards of the institutional and national research committee and with the 1964 Helsinki Declaration and its later amendments. This is an epidemiological study with anonymized, centrally collected, and online publicly available data. No patient consent or approval of the local ethics committee was required.
: Not applicable
: The authors declare that they have no competing interests.