Randomization method_ concealment_ link

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1126995/

Clinical Trial Registry of India_link

http://ctri.nic.in/Clinicaltrials/login.php

Observational studies_WHO policy

http://www.who.int/bulletin/volumes/85/11/07-045120.pdf

The Strengthening the Reporting of Observational Studies in

Epidemiology (STROBE) Statement: guidelines for reporting