[Shared decision making: an overview of international research literature]

Shared decision making (SDM) is a particular type of physician-patient-interaction to which the patient brings his/her individual preferences and the physician contributes the medical expertise. The aim of the SDM process is a treatment decision based on mutual agreement and active participation. This kind of decision-making is best effectuated in cases of diseases with medical uncertainty and/or differing patient outcome-treatment potentialities (e.g., breast- or prostate cancer). The concept of SDM is widely known in the English-speaking world. A database search with the keywords "shared decision" produced 301 relevant papers, of which 193 are theoretical and 108 empirical works. This paper gives an overview over the state of international research under special consideration in continental European literature. Different questions are explored with regard to potential methodological and contextual research fields. Present results indicate that the level of patient preference to participate in decisions is higher than their actual involvement. Results also prove that SDM leads to higher rates of satisfaction and better treatment results according to patients. Results regarding the efficacy of various intervention methods used to promote SDM, especially within different cultural contexts, are inconsistent. A great amount of research still needs to be done in this field.