Objective: This review aimed to clarify present knowledge about the factors which influence patients' preference for involvement in medical decision making.
Methods: A thorough search of the literature was carried out to identify quantitative and qualitative studies investigating the factors which influence patients' preference for involvement in decision making. All studies were rigorously critically appraised.
Results: Patients' preferences are influenced by: demographic variables (with younger, better educated patients and women being quite consistently found to prefer a more active role in decision making), their experience of illness and medical care, their diagnosis and health status, the type of decision they need to make, the amount of knowledge they have acquired about their condition, their attitude towards involvement, and the interactions and relationships they experience with health professionals. Their preferences are likely to develop over time as they gain experience and may change at different stages of their illness.
Conclusion: While patients' preferences for involvement in decision making are variable and the process of developing them likely to be highly complex, this review has identified a number of influences on patients' preference for involvement in medical decision making, some of which are consistent across studies.
Practice implications: By identifying the factors which might influence patients' preference for involvement, health professionals may be more sensitive to individual patients' preferences and provide better patient-centred care.