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Six of the authors (HD, MS, SD, EB, SM & MW) are employees of Cancer Council Victoria who were involved in the development, implementation and/or evaluation of two of the advertisements (Toxic fat & Piece of string) included in this analysis. TC was involved in the development of one of the advertisements (Toxic fat) included in this analysis. BJOH was a previous employee of the NSW Ministry of Health and was involved in the NSW implementation and specific evaluation of the Measure Up campaign. The authors declare that they have no other competing interests.
HD led the design, protocol development, project implementation, data analysis and manuscript preparation. MS coordinated project implementation and data collection, conducted the data analysis, and co-authored the manuscript. SD, EB and MW helped develop and refine the response measures and audience testing procedures, provided advice on data analysis and assisted with writing the manuscript. TC helped conceive the study, assisted with selecting the advertisements for testing, contributed to protocol development and assisted with writing the manuscript. SM assisted with developing and refining the study protocols and materials, identifying advertisements for testing, and project coordination. BJOH assisted with refining study protocols and helping to draft the manuscript. All authors read and approved the final manuscript.
Mass media communications are an important component of comprehensive interventions to address population levels of overweight and obesity, yet we have little understanding of the effective characteristics of specific advertisements (ads) on this topic. This study aimed to quantitatively test audience reactions to existing adult-focused public health television ads addressing overweight and obesity to determine which ads have the highest levels of message acceptance, argument strength, personalised perceived effectiveness and negative emotional impact.
1116 Australian adults aged 21-55 years recruited from a national online panel participated in this web-based study. Quotas were applied to achieve even numbers of males and females, those aged 21-29 years and 30-55 years, and those with a healthy weight (BMI = 18.5-24.9) and overweight/obesity (BMI = 25+). Participants were randomly assigned to view and rate four of eight ads that varied in terms of message content (health consequences, supportive/encouraging or social norms/acceptability) and execution style (graphic, simulation/animation, positive or negative testimonial, or depicted scene).
Toxic fat (a graphic, health consequences ad) was the top performing ad on all four outcome measures and was significantly more likely than the other ads tested to promote strong responses in terms of message acceptance, argument strength and negative emotional impact. Measure up (a negative testimonial, health consequences ad) performed comparably on personalised perceived effectiveness. Most ads produced stronger perceptions of personalised perceived effectiveness among participants with overweight/obesity compared to participants with healthy weight. Some ads were more likely to promote strong negative emotions among participants with overweight/obesity.
Findings provide preliminary evidence of the most promising content and executional styles of ads that could be pursued as part of obesity prevention campaigns. Ads emphasising the negative health consequences of excess weight appear to elicit stronger cognitive and emotional responses from adults with overweight/obesity. However, careful pre-testing of these types of ads is needed prior to their inclusion in actual campaigns to ensure they do not have unintended negative impacts such as increased stigmatisation of vulnerable individuals and increased levels of body dissatisfaction and/or eating-disordered behaviour among at-risk population sub-groups.