BACKGROUND-AIM:
Anti-tobacco communication campaigns are among the most acceptable and effective interventions for promoting smoking cessation. However, these campaigns often rely on broad targeting strategies that overlook individual characteristics, potentially limiting their impact. Tailoring messages to personality traits (which reflect stable, individualized patterns of cognitive reactivity : Extraversion, Neuroticism, Conscientiousness, Agreeableness, Openness) may enhance effectiveness and is now possible at scale thanks to digital tools. This study investigates which content features influence smoking cessation intention, and how this differs according to smokers’ personality profiles.

METHODS:
A total of 2,622 smokers completed the IPIP-NEO-120, a validated questionnaire describing personality through five dimensions, and were randomly exposed to three anti-smoking video advertisements selected from a pool of 38. The advertisements were coded using a taxonomy of 19 content features, reflecting the persuasive argument employed by the advertisements. After each exposure, participants rated the change in their intention to quit smoking. LASSO regressions, a machine learning method for variable selection and regularization, were used to identify significant interaction effects between personality traits and content features influencing smoking cessation intention.

RESULTS:
Extraversion (assertive and sociable trait) and Neuroticism (trait involving tension, insecurity, and anxiety) emerged as key moderators of message effectiveness, with specific content features amplifying or reducing cessation intention depending on these traits. Negative consequences of tobacco use (health dangers, dying, getting sick) were among the most powerful arguments to shift smoking cessation intention across all personality profiles. For each personality trait, specific interactions with content features were observed, either enhancing or reducing message impact on smoking cessation intention. For example, smokers scoring high on Conscientiousness (being hardworking, dedicated, and organized) or Agreeableness (likely to show affection and sympathy in social situations) were most influenced to stop smoking by messages showing people getting sick or injured than smokers scoring high in Extraversion.

CONCLUSIONS:
By highlighting the moderating role of personality on message effectiveness and its relations to specific content features, this study provides valuable insights for designing personality-tailored interventions. Our results pave the way for real-time adaptative messaging in digital tools, where content can dynamically be adjusted to individual profiles, enhancing the precision and effectiveness of digital health campaigns. Tobacco endgame, Strategies and policies to permanently end the tobacco epidemic.