Communicating Statistics and Risk

This article, published on the SciDev.Net website, proposes that translating statistics and risk in a readily understandable way is crucial to effective science communication, and offers techniques for journalists to be able to do this. According to author, journalists and scientists often present risk and probabilities in ways that cloud the intended message. To get audience's attention and trust, there is a need to clearly and accurately communicate scientific findings and their relevance. This often means that material from a scientific article must be translated into something widely understandable.

The article outlines several key strategies for journalists and communicators:

• Translating the evidence - Journalists must learn how to accurately and clearly make conclusions and evidence understandable to people, using their existing literacy and numeracy skills. For example, journalists can translate quantitative data into the closest equivalent in everyday speech and place the specific findings in parentheses. For example, writing "about half (51.2 per cent)" or "one-third (33 per cent)". As well, scientific articles often report in percentages so journalists should do the calculation and report "43 of the 215 people sampled (20 per cent)" rather than "20 per cent of a sample of 215 people".
• Individual versus population risk - the article cautions against confusing a general population estimate of risk, exposure, or probability, with individual situations. For example, in the United States, 12.7% of women will get breast cancer at some point in their lives. This statistic is often reported as, "one in eight women will get breast cancer," which is not a true reflection of individual risk. The article suggests that such risks be accompanied by information that explains variation in individual risk, such as age, diet, literacy level, location, education level, income, race, and ethnicity, and a host of other genetic and lifestyle factors.
• Absolute and relative risk - According to the article, choosing whether to use absolute or relative risk can make the same risk appear substantially different. Best practice is to clearly and concisely communicate both, along with the implications of those differences. The article uses an example of a fictitious study that reports on a new vaccine to prevent dengue fever. After five years, one vaccinated person is diagnosed with dengue, compared to four people who only received the placebo. The absolute risk of getting dengue after the new vaccine is 0.1 per cent, and is 0.4 per cent after the placebo. Headlines could accurately read, "New vaccine lowers risk of dengue by 0.3 per cent" or that the new vaccine cuts the relative risk as compared to the placebo by 75 per cent.
• The dangers of comparing risk - Commentators often try to communicate a new risk by comparing it to one their audience is already familiar with, but the article mentions that this can backfire and advises communicators to compare different risks sparingly as it is difficult to control how audiences will interpret metaphors. This is especially so when comparing risks that are controllable, to those that are not. Comparing the risk of a non-communicable disease, for example diabetes or heart disease, to a communicable disease likes HIV/AIDS or leprosy, is also inappropriate. The mechanisms of the diseases are different, and the varying social and cultural view of each makes the comparison a risky communication strategy.

The article concludes that to understand why people make different decisions about the same risk, communicators must understand their contexts and know the intended audience. It is also important for communicators and journalists to recognise their own skill and knowledge limits, and ask for clarification, rather than blindly repeating a technical specialist. The author advises to first get the basics correct, then add complexity in a way that both writer and readers can fully understand.