Misleading graphs in context: Less misleading than expected

Misleading graphs are a source of misinformation that worry many experts. Especially people with a low graph literacy are thought to be persuaded by graphs that misrepresent the underlying data. But we know little about how people interpret misleading graphs and how these graphs influence their opinions. In this study we focus on the effect of truncating the y-axis for a line chart which exaggerates an upgoing trend. In a randomized controlled trial, we showed participants either a normal or a misleading chart, and we did so in two different contexts. After they had seen the graphs, we asked participants their opinion on the trend and to give an estimation of the increase. Finally we measured their graph literacy. Our results show that context is the only significant factor in opinion-forming; the misleading graph and graph literacy had no effect. None of these factors had a significant impact on estimations for the increase. These results show that people might be less susceptible to misleading graphs than we thought and that context has more impact than a misleading y-axis.

Designing Visual Aids That Promote Risk Literacy: A Systematic Review of Health Research and Evidence-Based Design Heuristics

Background Effective risk communication is essential for informed decision making. Unfortunately, many people struggle to understand typical risk communications because they lack essential decision-making skills. Objective The aim of this study was to review the literature on the effect of numeracy on risk literacy, decision making, and health outcomes, and to evaluate the benefits of visual aids in risk communication. Method We present a conceptual framework describing the influence of numeracy on risk literacy, decision making, and health outcomes, followed by a systematic review of the benefits of visual aids in risk communication for people with different levels of numeracy and graph literacy. The systematic review covers scientific research published between January 1995 and April 2016, drawn from the following databases: Web of Science, PubMed, PsycINFO, ERIC, Medline, and Google Scholar. Inclusion criteria were investigation of the effect of numeracy and/or graph literacy, and investigation of the effect of visual aids or comparison of their effect with that of numerical information. Thirty-six publications met the criteria, providing data on 27,885 diverse participants from 60 countries. Results Transparent visual aids robustly improved risk understanding in diverse individuals by encouraging thorough deliberation, enhancing cognitive self-assessment, and reducing conceptual biases in memory. Improvements in risk understanding consistently produced beneficial changes in attitudes, behavioral intentions, trust, and healthy behaviors. Visual aids were found to be particularly beneficial for vulnerable and less skilled individuals. Conclusion Well-designed visual aids tend to be highly effective tools for improving informed decision making among diverse decision makers. We identify five categories of practical, evidence-based guidelines for heuristic evaluation and design of effective visual aids.

Measuring Graph Literacy without a Test: A Brief Subjective Assessment

BACKGROUND

Visual aids tend to help diverse and vulnerable individuals understand risk communications, as long as these individuals have a basic understanding of graphs (i.e., graph literacy). Tests of objective graph literacy (OGL) can effectively identify individuals with limited skills, highlighting vulnerabilities and facilitating custom-tailored risk communication. However, the administration of these tests can be time-consuming and may evoke negative emotional reactions (e.g., anxiety).

OBJECTIVES

To evaluate a brief and easy-to-use assessment of subjective graph literacy (SGL) (i.e., self-reported ability to process and use graphically presented information) and to estimate the robustness and validity of the SGL scale and compare it with the leading OGL scale in diverse samples from different cultures.

PARTICIPANTS

Demographically diverse residents (n = 470) of the United States, young adults (n = 172) and patients (n = 175) from Spain, and surgeons (n = 175) from 48 countries.

DESIGN

A focus group and 4 studies for instrument development and initial validation (study 1), reliability and convergent and discriminant validity evaluation (study 2), and predictive validity estimation (studies 3 and 4).

MEASURES

Psychometric properties of the scale.

RESULTS

In about 1 minute, the SGL scale provides a reliable, robust, and valid assessment of skills and risk communication preferences and evokes fewer negative emotional reactions than the OGL scale.

CONCLUSIONS

The SGL scale can be suitable for use in clinical research and may be useful as a communication aid in clinical practice. Theoretical mechanisms involved in SGL, emerging applications, limitations, and open questions are discussed.

Predicting biases in very highly educated samples: Numeracy and metacognition

We investigated the relations between numeracy and superior judgment and decision making in two large community outreach studies in Holland (n=5408). In these very highly educated samples (e.g., 30–50% held graduate degrees), the Berlin Numeracy Test was a robust predictor of financial, medical, and metacognitive task performance (i.e., lotteries, intertemporal choice, denominator neglect, and confidence judgments), independent of education, gender, age, and another numeracy assessment. Metacognitive processes partially mediated the link between numeracy and superior performance. More numerate participants performed better because they deliberated more during decision making and more accurately evaluated their judgments (e.g., less overconfidence). Results suggest that well-designed numeracy tests tend to be robust predictors of superior judgment and decision making because they simultaneously assess (1) mathematical competency and (2) metacognitive and self-regulated learning skills.

Communicating Health Risks With Visual Aids

Informed decision making requires that people understand health risks. Unfortunately, many people are not risk literate and are biased by common risk communication practices. In this article, we review a collection of studies investigating the benefits of visual aids for communicating health risks to diverse vulnerable people (e.g., varying in abilities, ages, risk characteristics, and cultural backgrounds). These studies show that appropriately designed visual aids are often highly effective, transparent, and ethically desirable tools for improving decision making, changing attitudes, and reducing risky behavior. Theoretical mechanisms, open questions, and emerging applications are discussed.

Simple but powerful health messages for increasing condom use in young adults

In a large longitudinal study involving young adults, we conducted an eight-hour STD educational intervention and examined the impact of the intervention on the efficacy of a message for promoting condom use. The message was framed in positive or negative terms and was presented visually or in numbers (percentages or frequencies). Results indicated that the numerical positive-framed message increased condom use among young adults who did not receive the intervention, whereas the numerical negative-framed message did not. Attitudes toward condom use along with changes in intentions to use condoms mediated this framing effect. In contrast, the positive-framed and negative-framed messages were equally and highly effective for promoting condom use when the messages were presented visually or when young adults received the STD educational intervention before reading the message, suggesting that the simple brochures featuring visual aids were as effective in changing attitudes and behavioral intentions as the extensive intervention. These findings add to a growing body of evidence detailing the mechanisms that allow well-constructed visual aids to be among the most effective, transparent, memorable, and ethically desirable means of risk communication. Clinical and public health implications are discussed.