Funding for this research was provided by:
Text and Data Mining valid from 2018-06-28
Received: 26 February 2018
Accepted: 23 June 2018
First Online: 28 June 2018
Compliance with ethical standards
: The authors declare that they have no competing interests.
: The study was approved by the National Ethical Committee (1-10-72-216-15) and the Danish Data Protection Agency (1-16-02-490-15).
: Oral and written information was given to parents and patients, and written consent from patients over 15 years and parents was received.