Simple tools for understanding risks: from innumeracy to insight

  title={Simple tools for understanding risks: from innumeracy to insight},
  author={Gerd Gigerenzer and Adrian G. K. Edwards},
  journal={BMJ : British Medical Journal},
  pages={741 - 744}
Bad presentation of medical statistics such as the risks associated with a particular intervention can lead to patients making poor decisions on treatment. Particularly confusing are single event probabilities, conditional probabilities (such as sensitivity and specificity), and relative risks. How can doctors improve the presentation of statistical information so that patients can make well informed decisions? The science fiction writer H G Wells predicted that in modern technological… 
Making sense of diagnostic tests likelihood ratios
In the teachings of evidence-based medicine, an easier, intuitive way to interpret the results of diagnostic studies based on 2 elements: the likelihood ratio of the test and the pretest odds is found.
Helping Doctors and Patients Make Sense of Health Statistics
Evidence is provided that statistical illiteracy is common to patients, journalists, and physicians and that information pamphlets, Web sites, leaflets distributed by the pharmaceutical industry, and even medical journals often report evidence in nontransparent forms that suggest big benefits of featured interventions and small harms.
The illusion of certainty
In everyday life we have to make choices, which involve a degree of uncertainty and risk, however many doctors are not able to take proper decisions and fail to understand the advantages and the
Psychosocial aspects of risk appraisal
All health care professionals need to be aware of the impact that their own communication may have on patients' understanding and on some of the psychological issues that influence the lay populations' beliefs and behaviours.
Transparency in Risk Communication
This chapter deals with tools for transparency in risk communication and graphical and analog representations of risk, which have long enjoyed the status of being more readily accessible to human understanding than long‐winded symbolic representations.
Improving Understanding of Health-Relevant Numerical Information
This chapter discusses why risks are often not communicated in a transparent and understandable way and why this is problematic, and illustrates, using an example from mammography screening, what transparent risk communication could look like.
Communicating prostate cancer risk: what should we be telling our patients?
The oft‐used statement “men are more likely to die with prostate cancer than from prostate cancer” is misleading, particularly for men diagnosed in their 50s or 60s.
Can postponement of an adverse outcome be used to present risk reductions to a lay audience? A population survey
Lay people can discriminate between levels of treatment effectiveness when they are presented in terms of postponement of an adverse event, indicating that such postponement is a comprehensible measure of effectiveness.
Heart Forecast for cardiovascular risk assessment
While it is widely considered acceptable to curtail personal freedoms to reduce the threat of rare but aggregated attack, restriction of personal choice of food in order to prevent the 2000 times more likely occurrence of cardiovascular disease (CVD) is almost universally considered unacceptable.
How to Foster Citizens’ Statistical Reasoning: Implications for Genetic Counseling
Cognitive psychology has identified simple and effective tools for improving statistical reasoning that can help to improve the public’s understanding of diagnostic test results.


Calculated Risks: How to Know When Numbers Deceive You
Cognitive scientist Gerd Gigerenzer explains how the authors can overcome their ignorance of numbers and better understand the risks they may be taking with their money, their health, and their lives.
Explaining risks: turning numerical data into meaningful pictures
Whether the shift towards a greater use of information in consultations is helpful and how information can be used without losing the benefits that are traditionally associated with the art, rather than the science, of medicine are explored.
Strategies to help patients understand risks
  • J. Paling
  • Medicine
    BMJ : British Medical Journal
  • 2003
Doctors can now choose from a “toolbox” of simple, practical, time efficient techniques that benefit the widest possible variety of patients.
Using natural frequencies to improve diagnostic inferences
Representing information in natural frequencies is a fast and effective way of facilitating diagnosis insight, which in turn helps physicians to better communicate risks to patients, and patients to better understand these risks.
How can we help people make sense of medical data?
This tutorial aims to improve critical reading skills by teaching people about risk and showing them what to look for in statements about risk, and how to put disease risk and treatment benefit in context.
Presenting risk information--a review of the effects of "framing" and other manipulations on patient outcomes.
It is suggested that providing more information, and which is more understandable to the patient, is associated with improved patient knowledge and a greater wariness to take treatments or participate in trials, and can contribute to efforts to improve communication between professionals and patients.
Evidence based purchasing: understanding results of clinical trials and systematic reviews
The method of reporting trial results has a considerable influence on the health policy decisions made by health authority members, including mammography and cardiac rehabilitation.
How risks of breast cancer and benefits of screening are communicated to women: analysis of 58 pamphlets
The willingness of health purchasers to fund mammographic screening has been shown to be significantly influenced by the way in which data about effectiveness are presented: a programme achieving a 30% reduction in relative risk was more likely to be funded than two others described in terms of absolute risk reduction.
Does the frame affect the picture? A study into how attitudes to screening for cancer are affected by the way benefits are expressed
Health professionals must choose between framing the benefits of screening in the most positive light, to enhance participation rates, and presenting information in such a way as to reduce framing effects—for example, by expressing the benefits in a variety of forms.
Disease impact number and population impact number: population perspectives to measures of risk and benefit.
Two new statistics are proposed, which should allow the impact of an intervention to be seen in the context of the broader population and take account of the number of people in the population with the disease.