Effectiveness of decision aids on cancer-screening decision-making: an umbrella review protocol

INTRODUCTION: Although systematic reviews have shown how decision aids about cancer-related clinical decisions improve selection of key options and shared decision-making, whether or not particular decision aids, defined by their specific presentation formats, delivery methods and other attributes, can perform better than others in the context of cancer-screening decisions is uncertain. Therefore, we planned an overview to address this issue by using standard umbrella review methods to repurpose existing systematic reviews and their component comparative studies. METHODS AND ANALYSIS: We will search PubMed, Embase, the Cochrane Database of Systematic Reviews and the Database of Abstracts of Reviews of Effects from inception through 31 December 2021 with no language restriction and perform full-text evaluation of potentially relevant articles. We will include systematic reviews of randomised controlled trials or non-randomised studies of interventions that assessed a decision aid about cancer-screening decisions and compared it with an alternative tool or conventional management in healthy average-risk adults. Two reviewers will extract data and rate the study validity according to standard quality assessment measures. Our primary outcome will be intended and actual choice and adherence to selected options. The secondary outcomes will include attributes of the option-selection process, achieving shared decision-making and preference-linked psychosocial outcomes. We will qualitatively assess study, patient and intervention characteristics and outcomes. We will also take special care to investigate the presentation format, delivery methods and quality of the included decision aids and assess the degree to which the decision aid was delivered and used as intended. If appropriate, we will perform random-effects model meta-analyses to quantitatively synthesise the results. ETHICS AND DISSEMINATION: Ethics approval is not applicable as this is a secondary analysis of publicly available data. The review results will be submitted for publication in a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42021235957.