E-cigarettes Warning Labels and Modified Risk Statements: Tests of Messages to Reduce Recreational Use.

Objectives: We tested how variations of the warning message on e-cigarette packages influenced risk and ambiguity perceptions, and whether including a modified risk statement on the package influenced how the warning label was perceived.

Method: A 4 (warning text) × 2 (modified risk statement), plus control, experiment (N = 451) was conducted.

Results: Smoking status, sex, and the language used in the warning statements interacted to influence risk perceptions. For example, non-smoking women perceived e-cigarettes with the FDA text at 30% of the package as riskier than the FDA text at 12-point type. Additionally, including a modified risk statement on the package increased ambiguity among non-smokers, as did an abstract warning label.

Conclusions: When evaluating the effectiveness of warning label text, it is important to consider smoking status and sex. Additionally, including modified risk statements on the package with the warning label could potentially increase ambiguity among non-smokers.