Article History
First Online: 5 March 2020
Compliance with Ethical Standards
:
: Nader Mehri declares that he has no conflict of interest. Dr. Mahmood Messkoub declares that he has no conflict of interest. Dr. Suzanne Kunkel declares that she has no conflict of interest.
: Not applicable. This study uses secondary data that are aggregated by age groups. The data is publicly available.
: This article does not contain any studies with human participants or animals performed by any of the authors.This study uses secondary data that are aggregated by age groups. The data is publicly available.