Data associated with 'Optimization of an information leaflet to influence medication beliefs in women with breast cancer: a randomized factorial experiment'

Most women with breast cancer are prescribed adjuvant endocrine therapy (AET) to prevent recurrence and mortality, but adherence is suboptimal. Negative beliefs about the necessity of AET and high concerns are barriers to adherence. We aimed to optimize the content of an information leaflet intervention, to support AET beliefs. We conducted an online screening experiment using a 2^5 factorial design to optimize the leaflet. The leaflet had five components, each with two levels; 1) diagrams about AET mechanisms (on/off); 2) infographics displaying AET benefits (enhanced/basic); 3) AET side-effects (enhanced/basic); 4) answers to AET concerns (on/off); 5) breast cancer survivor (patient) input: quotes and photographs (on/off). Healthy adult women (n=1604), recruited via a market research company, were randomized to one of 32 experimental conditions, which determined the levels of components received. Participants completed the beliefs about medicines questionnaire before and after viewing the leaflet. Note: This dataset only contains data for the primary outcome (beliefs about AET). A dataset containing secondary outcome data will be shared in due course.