Communicating information concerning potential medication harms and benefits: What gist do numbers convey?

Fuzzy trace theory was used to examine the effect of information concerning medication benefits and side-effects on willingness to use a hypothetical medication.

Participants (N=999) were recruited via Amazon Mechanical Turk. Using 3×5 experimental research design, each participant viewed information about medication side effects in 1 of 3 formats and information about medication benefits in 1 of 5 formats. For both side-effects and benefits, one format presented only non-numeric information and the remaining formats presented numeric information.

Individuals in the non-numeric side-effect condition were less likely to take the medication than those in the numeric conditions (p<0.0001). In contrast, individuals in the non-numeric benefit condition were more likely to take the medication than those in the numeric conditions (p<0.0001).

Our findings suggest that non-numeric side-effect information conveys the gist that the medication can cause harm, decreasing willingness to use the medication; whereas non-numeric benefit information has the opposite effect.

Presenting side-effect and benefit information in non-numeric format appears to bias decision-making in opposite directions. Providing numeric information for both benefits and side-effects may enhance decision-making. However, providing numeric benefit information may decrease adherence, creating ethical dilemmas for providers.