Text and Data Mining valid from 2018-10-05
First Online: 5 October 2018
Compliance with Ethical Standards
: All authors declare that they have no conflict of interest.
: All procedures performed in this study were in accordance with the Ethical Standards of the Institutional Research Committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.
: Before entry into the current study, informed consent was obtained from the parents of all child participants included in the study.