A econometrician by training, Graham focuses on health system efficiency, policy evaluation, and pricing and reimbursement in pharmaceutical markets. Alongside his position at OHE, Graham is an Honorary Professor at City, University of London and is a Fellow of Royal Statistical Society, Higher Education Academy and member of Royal Economic Society.

His current research interests include the measurement and determinants of productivity in healthcare especially labour productivity; the industrial organisation of healthcare especially tariffs and competition; real–world evidence in health economic evaluation; and big data in the health and life sciences. He is best known for this work on the economics of staffing and skill mix in the English NHS, which was critical to the development of the NICE Guidelines on Safe Staffing.