Funding for this research was provided by:
medical research institute Colombo (no16/2018/MRI)
Received: 16 November 2021
Accepted: 12 February 2022
First Online: 5 March 2022
: Ethical approval for the study was obtained from the Ethics review committee of the Faculty of Medicine, University of Kelaniya (P/217/08/2017). The trial was registered with the Sri Lanka trial registry (Registration No: SLCTR/ 2018/002 Date of Registration: 23rd January 2018). Parents indicated written consent for students, and students indicated assent to participate in the study.
: Not applicable.
: The authors declare no competing interests.