Khawaja, Shabnum, Mohammad Asif, Samina Naz Mukry, and Tahir Sultan Shaamsi. “Possible Correlation of Electrochemiluminescence Based Numerical Cut off Index Value With Concentration of Anti-SARS-CoV-2 Antibody: Is It Worth Reporting?”. Journal of Public Health Research 10, no. 1 (February 26, 2021). Accessed April 20, 2021. https://jphres.org/index.php/jphres/article/view/2079.