Patient-centred and economic effectiveness of a decision aid for patients with age-related cataract in China: study protocol of a randomised controlled trial

INTRODUCTION: The need for cataract surgery is on the rise due to our ageing population and high demands for greater visual functioning. Although the majority of patients want to participate in a shared decision-making process, no decision aid has been available to improve the quality of decision. The present study aims to determine whether a decision aid increases informed decision about cataract surgery. METHODS AND ANALYSIS: A parallel randomised controlled trial (772 participants) will be conducted. The decision aid will be implemented among patients with any age-related cataract in Yuexiu District, which is socioeconomically representative of a major metropolitan region in Southern China. Participants will be randomly assigned to receive either a patient decision aid or a traditional booklet, and they will complete three surveys: (1) baseline assessment before the intervention (time point (T)1), 2 weeks (T2) and 1 year (T3) after the intervention. The control group receives a traditional booklet with standard general information developed by the National Eye Institute to help patients understand cataract, whereas the intervention group receives a patient decision aid that includes not only the standard general information, but also the quantitative risk information on the possible outcomes of cataract surgery as well as value clarification exercise. The primary study outcome is the informed decision, the percentage of patients who have adequate knowledge and demonstrate consistency between attitudes and intentions. Secondary outcomes include perceived importance of cataract surgery benefits/harms, decision conflict and confidence, anticipated regret and booklet utilisation and acceptability at 2 weeks, and surgical rates and a cost–utility estimate of the decision aid at 1 year. ETHICS AND DISSEMINATION: Ethics approval was obtained from the Ethics Committee of Zhongshan Ophthalmic Center (reference number: 2019KYPJ090). Results will be published in peer-reviewed journals and presented at scientific meetings for academic audiences. TRIAL REGISTRATION NUMBER: NCT03992807.