Tarani is a Professor of Medical Sociology. He is the head of the department of Sociology and the director of the Methods Hub and Social Science Research Centre in the Faculty of the Social Sciences at the University of Hong Kong. He joined the Department of Sociology in August 2021 and was formerly the Head of Department of Social Statistics at the University of Manchester. He is a member of the ESRC Strategic Advisory Network Strategic Advisory Network and a fellow of the Academy of Social Sciences. He was formerly the editor-in-chief of the journal Sociology, the flagship journal of the British Sociological Association, and is currently an international advisory board member of the journal Sociology of Health & Illness. He was a panel member of the Sociology Unit of Assessment for the 2021 Research Excellence Framework, UK. He obtained his DPhil in Sociology from Nuffield College, University of Oxford in 1998.

His research is primarily on the social determinants of health, focusing on health inequalities and psychosocial factors, and the analysis of longitudinal cohort studies. His major research contributions have been on understanding the role of chronic stress related biomarkers in relation to psychosocial stressors such as poor working conditions.