Ethics approval and consent to participate
All methods were carried out in accordance with the relevant guidelines and regulations of Damascus University. Our study along with the methods were approved by the institutional review board and ethical review committee of Damascus University. (Approval number: NO. 2473).The study was carried out in Syria and the age for citizens to be fully in control as to legal matters including healthcare issues (the legal age) is 18 here (not 16). Hence, we had to ask all willing participants who were under 18 of age at that time to make their responsible carers/guardians sign the approval to participate on their behalf.