Independent or synergistic? Effects of varying size and using pictorial images in tobacco health warning labels

Introduction: Legal challenges have blocked the implementation of large, pictorial health warning labels (HWLs) in the U.S. In light of future legal questions the U.S. Food and Drug Administration may face in proposing alternative HWLs, we examined whether less restrictive HWL versions on the front of packs—smaller HWLs and/or text-only HWLs that do not include pictorial imagery—may be sufficient to promote cognitive and affective outcomes associated with smoking cessation. Methods: We recruited low-income smokers in two separate experiments through field-based recruitment methods (Study 1, N = 497) or Amazon Mechanical Turk (MTurk) (Study 2, N = 495). In both studies, we randomly assigned participants to a no-HWL control condition or one of four HWL conditions in a 2 (pictorial vs. text-only) × 2 (50% vs. 30% size) between-subjects design. Results: Relative to text-only HWLs, pictorial HWLs increased negative affect but not risk belief acceptance, cognitive elaboration about smoking harms, or quit intentions. The 50% HWLs increased quit intentions relative to the control condition in both studies. The 50% HWLs also outperformed the 30% HWLs in promoting quit intentions in Study 2. Subsequent analyses revealed that this effect in Study 2 may have been driven by the 50% HWLs strengthening the relationship between risk-related thoughts and intentions, although there was no evidence for this pattern in Study 1. We found no evidence for interaction effects between the pictorial and size manipulations. Conclusions: Our findings suggest that 50% HWLs, whether pictorial or text-only, can encourage low-income smokers to consider quitting under some conditions.