Decision Aids: Improving methods of presenting risk information


Even though we know that risk information should be included in decision aids, it is not clear what the best ways are to present this information. The way in which risk information is presented can affect how people make decisions. We are interested in learning how different presentations affect decision making and what presentations are most helpful to patients to make clear, unbiased decisions.

Framing effects. People’s treatment choices depend on whether treatment benefits are framed in terms of survival or mortality. For example, we have examined biases in people’s perception of survival curves (they pay too little attention to the time duration of the risk) and shown that mortality curves are less susceptible to this bias.

Mistaking the meaning of risk statistics when attempting to understand changes in health risks. Some people have trouble distinguishing between baseline risk information, total risk after treatment, and the additional/prevented risk caused by intervention. Several of our studies have focused on the benefits of using presentations that focus attention on the incremental risk or benefit of an intervention.

The effects of different graphical risk presentations. Many different graphical formats have been used to communicate risk information, including bar graphs and pie charts. We have published a series of papers arguing that a different format, pictographs (icon arrays), has significant advantages over other approaches. Graphics can also affect how people interpret how risks change over time (e.g., survival vs. mortality curves, or sets of pictographs vs. line graphs).

Tradeoffs associated with adjuvant therapies. While adjuvant chemotherapy can greatly reduce the overall risk of cancer recurrence, the incremental risk reduction from adding chemotherapy can be quite small. Yet the chemotherapy has a significant quality of life burden associated with it. Simplifying the graphical presentations of this information by removing unnecessary information and using pictographs may improve patients’ understanding of the size of the risk reduction.

Ambiguous probabilities. It is important to communicate uncertainty to patients when informing them about the probabilities of experiencing relevant health outcomes. We are exploring different methods for communicating ambiguity, as well as studying how ambiguous information affects people’s perceptions, affective reactions, and treatment choices in making decision aids.