Dr Lei Si is an Associate Professor in Health Services Management at Western Sydney University. He also holds appointments such as an Honorary Senior Fellow at the George Institute for Global Health and an Adjunct Professor at Nanjing Medical University. 

Dr Si’s research applies health economics methods to inform the efficient and equitable allocation of healthcare resources. His work spans cost-of-illness analysis, health-related quality of life measurement, and economic evaluation, including both trial-based and model-based approaches.

Dr Si has published over 130 papers in peer-reviewed journals. Many studies were published in top health economics or clinical research journals such as the New England Journal of Medicine, JAMA, the Lancet Regional Health - Western Pacific, Circulation, BMJ Global Health, JAMA Network Open, Value in Health, Osteoporosis International, Quality of Life Research and Pharmacoeconomics. Lei's work has successfully attracted competitive funding of over $9 million from the NHMRC and MRFF (Australia), CIHR (Canada), NSFC (China), CMB (US), etc. 

Dr Si is Editor-in-Chief of Health Economics Review (Q1 in Economics) and an Associate Editor for BMJ Global Health (Q1 in Health Policy). He also serves on the editorial boards of several journals, including Osteoporosis International, Advances in Therapy, Frontiers in Public Health etc. He has been an External Evaluator of the Pharmaceutical Benefits Advisory Committee (PBAC).