The world health report

Chapter 3


Framing the information on risks

After defining a particular risk problem, determining which people are at risk, measuring exposure levels and selecting the risk outcomes, all this information has to be presented to decision-makers. How the information is presented usually depends on whether it is meant to influence individuals or national policy-makers. The way the information is presented is often referred to as "framing" (see Box 3.3).

Box 3.3 Framing risks to health: choosing presentations

  • Positive or negative framing? Striking changes in preference can result from framing the risk in either positive or negative terms, such as lives saved or lives lost, rates of survival or mortality, improving good health or reducing risks of disease.
  • Relative or absolute risks? Although relative risks are usually better understood, it can be very important to present absolute changes as well.
  • Percentages or whole numbers? Probabilities are better understood as percentage changes than by comparison of whole numbers.
  • Whole numbers or an analogy? Whole numbers may be less well understood than an example or analogy for the size of an adverse event.
  • Small or large numbers? A small number of deaths is more easily understood than a large number, which is often incomprehensible.
  • Short or long periods? A few deaths at one time or over a short period, as in a tragic accident, often have more impact than a larger number of deaths occurring discretely over a longer period of time.

Source: (28).

Numerous research studies have demonstrated that different but logically equivalent ways of presenting the same risk information can lead to different evaluations and decisions. A famous example is the study which asked people to imagine that they had lung cancer and had to choose either surgery or radiation therapy (29). The choices were strikingly different, depending on whether the results of treatment were framed as the probability of surviving for varying lengths of time after the treatment or in terms of the probability of dying. When the same results were framed in terms of dying, the choice of radiation therapy over surgery increased from 18% to 44%. The effect was just as strong for physicians as for lay persons.

All presentations of risk information use frames that can exert a strong influence on decision-makers. However, if all information is equally correct, there are really no "right" or "wrong" frames -- just different frames. How risk information is framed and communicated to individuals or policy-makers, scientists or the general public can be of crucial importance in achieving maximum influence over public perceptions. It can also be very important in convincing the public health community and high-level policy-makers about the importance of risks to health and the value of adopting different interventions.