He is a biostatistician and his research interests include the epidemiology of cardiovascular disease, cancer, arthritis and cohort studies of drug utilisation patterns and their effects. His area of expertise is methodological research on the development of new statistical methodology and collaborative research, in which these new methods are applied in epidemiologic and clinical studies. The main focus is on flexible modelling of survival data, including changes in relative risks over time, detecting thresholds and lags in the effects of risk factors and interventions, and the impact of using ecologic variable on estimated risks.