This is the first study using a representative sample to show that people greatly overestimate the intended frequency of the verbal risk descriptors used to label side effect risk in patient information leaflets, especially when describing mild side effects.

Small changes to the wording used in the verbal risk descriptors will not solve this problem; the issue was the same for the three different forms of wording that we tested.

More radical changes (including abandoning the use of verbal risk descriptors) should be considered.