Text and Data Mining valid from 2019-02-01
Received: 24 August 2018
Revised: 27 December 2018
Accepted: 10 January 2019
First Online: 1 February 2019
Compliance with ethical standards
: This study was approved by the Medical Ethical Commission. All procedures performed in studies were done according to regular yearly medical care for children with Down syndrome, studied in retrospect, and in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
: The authors declare that they have no competing interests.