[Limits in health services research].

Current limitations in health services research (HRS) in Germany are caused by issues of research funding, interest-driven commissioning, and restricted research conditions due to the structural and organizational context of the German health system. Methodological challenges arise in the validation and generalizability of routine data. There are substantial risks of bias in non-controlled interventional studies. In order to overcome these limitations and to improve the standing and quality of HRS in Germany, political opinion leaders and stakeholders need to be provided with continuous information on the need and potential of HRS. Methodological standards are needed for the evaluation of routine data, and principles of evidence-based medicine must be applied in all research addressing the effectiveness of health care interventions.