[What is evidence-based concerning quality management? Thoughts about an apparently simple question].

Quality management has become more important due to the growing pressure for change within the healthcare sector. Responsible for this are driving forces that include not only competition and legislation, but also society. Therefore, quality management has developed especially in the direction of structural organization, process orientation, and professionalism. However, there is a lack of information concerning the scientific, evidence-based evaluation of activities, measures, and projects. Current studies and data are not able to answer questions concerning a strong correlation between quality management activities and treatment effects, and the influence on the whole system remains open. The reason for this is the complexity of the different dynamic factors influencing the benefit assessment. Single investigations can only indicate specific aspects of the multifaceted term quality analysis. There is a high demand for scientific and proven methods as well as for the understanding that scientifically established answers can only be given to well-defined and specific questions.