Research fields include economic evaluation of health care as well as health services research, with a focus on care for the mentally ill and the elderly. Currently, methods are developed and tested to measure preference-based valuations of health-related quality of life and costs in different diagnosis groups. In addition, cost-of-illness studies are carried out and disease models are developed as a basis for decision-analytic evaluation studies. Furthermore, cost-effectiveness analyses of new preventive, diagnostic and therapeutic health technologies for patients from different disease groups are conducted and new forms of funding for mental health care are evaluated. Moreover, one research focus is on the field of health care epidemiology. This research area is located at the interface of health services research, health economics and epidemiology. Interdisciplinary questions of health services research are investigated empirically, also with a focus on health services research in old age and mental illness, and mainly based on data from cohort studies.