A Systematic Literature Review of Shared Decision Making in Cancer Care (Preprint)

BACKGROUND Shared decision making (SDM) is a process in which health care providers and patients relate to and influence each other as they collaborate in making decisions about patients’ health care. Hypothesized as a means to improve quality of care, successful applications of SDM in routine cancer care have not been widely documented. OBJECTIVE The objective of this study was to examine the literature to determine if elements of SDM implementation between cancer patients and their clinicians were more or less successful at improving the quality of care and health outcomes. METHODS A systematic literature search of SDM approaches and outcomes in cancer care was conducted using PubMed and EMBASE. An integrative model for SDM was used to classify elements included in SDM intervention studies and the resulting outcomes. RESULTS From 1,018 unique publications, 23 articles meeting eligibility criteria were included. Only three studies addressed elements of patient-clinician interaction as part of the study objectives. Interventions included decision aid (DA) evaluation (n=22) and clinician communication training (n=1). SDM elements commonly included were: defining/explaining the problem (n=23); presenting options (n=19); discussing pros and cons (n=17); assessing patient priorities and preferences (n=17); clinician knowledge and recommendations (n=15); and making or deferring treatment decisions (n=12). The most frequently-measured outcomes were patient-reported outcomes including treatment preference or decision (n=12), decisional conflict (n=10), patient satisfaction (n=10), patient participation (n=9), and patient knowledge (n=7). No clear patterns demonstrating relationships between SDM elements and outcomes were identified. Information on how patients and clinicians utilized DA information to promote SDM was limited. CONCLUSIONS Evaluation of SDM in cancer care has been increasing. However, the term “SDM” was generally applied to studies that focused on the development and/or evaluation of DAs which limited the current analyses to a review of SDM elements as part of the DAs. Most studies did not include a qualitative or quantitative measure of SDM specific to patient-clinician communication and interaction. Instead, there was an underlying assumption that SDM occurred organically with DA implementation. Without a qualitative or quantitative measure of SDM, identification of successful SDM elements and their relationships to patient outcomes remains unclear. Additional research is warranted on SDM implementation and measurement in real-world cancer care settings.