skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Title: Current Best Practice for Presenting Probabilities in Patient Decision Aids: Fundamental Principles
Background Shared decision making requires evidence to be conveyed to the patient in a way they can easily understand and compare. Patient decision aids facilitate this process. This article reviews the current evidence for how to present numerical probabilities within patient decision aids. Methods Following the 2013 review method, we assembled a group of 9 international experts on risk communication across Australia, Germany, the Netherlands, the United Kingdom, and the United States. We expanded the topics covered in the first review to reflect emerging areas of research. Groups of 2 to 3 authors reviewed the relevant literature based on their expertise and wrote each section before review by the full authorship team. Results Of 10 topics identified, we present 5 fundamental issues in this article. Although some topics resulted in clear guidance (presenting the chance an event will occur, addressing numerical skills), other topics (context/evaluative labels, conveying uncertainty, risk over time) continue to have evolving knowledge bases. We recommend presenting numbers over a set time period with a clear denominator, using consistent formats between outcomes and interventions to enable unbiased comparisons, and interpreting the numbers for the reader to meet the needs of varying numeracy. Discussion Understanding how different numerical formats can bias risk perception will help decision aid developers communicate risks in a balanced, comprehensible manner and avoid accidental “nudging” toward a particular option. Decisions between probability formats need to consider the available evidence and user skills. The review may be useful for other areas of science communication in which unbiased presentation of probabilities is important.  more » « less
Award ID(s):
2017651
PAR ID:
10296672
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Medical Decision Making
Volume:
41
Issue:
7
ISSN:
0272-989X
Page Range / eLocation ID:
821 to 833
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. null (Ed.)
    Background Decision aid developers have to convey complex task-specific numeric information in a way that minimizes bias and promotes understanding of the options available within a particular decision. Whereas our companion paper summarizes fundamental issues, this article focuses on more complex, task-specific aspects of presenting numeric information in patient decision aids. Methods As part of the International Patient Decision Aids Standards third evidence update, we gathered an expert panel of 9 international experts who revised and expanded the topics covered in the 2013 review working in groups of 2 to 3 to update the evidence, based on their expertise and targeted searches of the literature. The full panel then reviewed and provided additional revisions, reaching consensus on the final version. Results Five of the 10 topics addressed more complex task-specific issues. We found strong evidence for using independent event rates and/or incremental absolute risk differences for the effect size of test and screening outcomes. Simple visual formats can help to reduce common judgment biases and enhance comprehension but can be misleading if not well designed. Graph literacy can moderate the effectiveness of visual formats and hence should be considered in tool design. There is less evidence supporting the inclusion of personalized and interactive risk estimates. Discussion More complex numeric information. such as the size of the benefits and harms for decision options, can be better understood by using incremental absolute risk differences alongside well-designed visual formats that consider the graph literacy of the intended audience. More research is needed into when and how to use personalized and/or interactive risk estimates because their complexity and accessibility may affect their feasibility in clinical practice. 
    more » « less
  2. Risk communication is critically important, for both patients and providers. However, people struggle to understand risks because there are inherent biases and limitations to reasoning under uncertainty. A common strategy to enhance risk communication is the use of decision aids, such as charts or graphs, that depict the risk visually. A problem with prior research on visual decision aids is that it used a metric of performance that confounds 2 underlying constructs: precision and bias. Precision refers to a person’s sensitivity to the information, whereas bias refers to a general tendency to overestimate (or underestimate) the level of risk. A visual aid is effective for communicating risk only if it enhances precision or, once precision is suitably high, reduces bias. This article proposes a methodology for evaluating the effectiveness of visual decision aids. Empirical data further illustrate how the new methodology is a significant advancement over more traditional research designs. 
    more » « less
  3. The onus on the average person is greater than ever before to make sense of large amounts of readily accessible quantitative information, but the ability and confidence to do so are frequently lacking. Many people lack practical mathematical skills that are essential for evaluating risks, probabilities and numerical outcomes such as survival rates for medical treatments, income from retirement savings plans or monetary damages in civil trials. In this Review, we integrate research on objective and subjective numeracy, focusing on cognitive and metacognitive factors that distort human perceptions and foment systematic biases in judgement and decision making. Paradoxically, an important implication of this research is that a literal focus on objective numbers and mechanical number crunching is misguided. Numbers can be a matter of life and death but a person who uses rote strategies (verbatim representations) cannot take advantage of the information contained in the numbers because 'rote' strategies are, by definition, processing without meaning. Verbatim representations (verbatim is only surface form, not meaning) treat numbers as data as opposed to information. We highlight a contrasting approach of gist extraction: organizing numbers meaningfully, interpreting them qualitatively and making meaningful inferences about them. Efforts to improve numerical cognition and its practical applications can benefit from emphasizing the qualitative meaning of numbers in context - the gist - building on the strengths of humans as intuitive mathematicians. Thus, we conclude by reviewing evidence that gist training facilitates transfer to new contexts and, because it is more durable, longer-lasting improvements in decision making. 
    more » « less
  4. Advantages and disadvantages exist for presenting numeric information in science communication. On the one hand, public innumeracy and experts’ concerns about providing numbers suggest not always showing them. On the other hand, people often prefer getting them, and their provision can increase comprehension, trust, and healthy behaviors while reducing risk overestimates and supporting decision-making autonomy. Presenting numeric facts without considering their comprehensibility and usability, however, is like throwing good money after bad. We summarize research concerning three theory-based strategies that improve the understanding and use of numbers by decreasing cognitive effort (e.g., doing the math for the audience), being consistent with principles of numeric cognition, and providing affective meaning. 
    more » « less
  5. A learning strategy analysis was performed on the Emotive Virtual Patient System, an augmented reality platform that teaches medical students doctor-patient communication skills. The Emotive Virtual Patient System is a complex mixed reality platform that includes both virtual and human peers/instructors who use natural language processing to provide feedback and dialog modeling as a means to improve patient communication learning outcomes. The learning strategy analysis (i.e., system learning strategy/component review, literature review, and heuristic evaluation of best practices) was conducted on the early system plans to determine its potential in supporting student learning and to provide shortand-long-term design considerations. The analysis identified three major categories for potential consideration: verbal interactions, user groups/system objective monitoring, and security. Specific recommendations were given for each of these areas, as supported by the literature. 
    more » « less