Numbers are an essential part of many health communications and medical decision making situations. Yet, it is often unclear how best to communicate numbers to patients or the public to achieve different goals. Although there is a large and ever growing literature testing different types of risk and health number communications, both methodological and conceptual differences have made it difficult to summarize the findings from past work. In this seminar, Jessica Ancker (Vanderbilt U.) and Brian Zikmund-Fisher (U. Michigan) will provide an overview and some preliminary findings from their National Library of Medicine-funded R01 award that is systematically reviewing over 400 papers to create evidence-based guidance for health number communication. Drs. Ancker and Zikmund-Fisher will present the conceptual taxonomies from their recently published paper (Risk Analysis, 2022) and discuss how separately considering the specific goals, formats, and structures of health data communications, and the cognitive tasks required of the reader, can lead to clearer insights from the literature. They will then provide an overview of their innovative review methodology, share some of the insights learned from the review so far, and present a preliminary version of the web-based tool that will soon enable health communicators to find the evidence that most pertains to the number communications that they are designing.