Received: 27 January 2021
Accepted: 28 June 2021
First Online: 1 September 2021
: Ethics approval and consent to participate: Danish law stipulates that consent and ethical approval from the ethical committee is not necessary and it is not possible to obtain them when doing research on registered data with all patient data anonymized.
: Not relevant.
: The authors declare that they have no competing interests, and they were not involved in the journal’s review of or decisions related to, this manuscript.