Text and Data Mining valid from 2019-11-25
Received: 4 August 2019
Revised: 7 October 2019
Accepted: 7 November 2019
First Online: 25 November 2019
Compliance with ethical standards
: The authors declare that they have no conflict of interest.
: Informed consent was obtained from parents or legal guardians of all the patients for the participation of their children in the study which was approved by the Local Ethics Committee.