The effectiveness of graphic health warnings on tobacco products: a systematic review on perceived harm and quit intentions

BACKGROUND: Examination of the format and framing of the graphic health warnings (GHWs) on tobacco products and their impact on tobacco cessation has received increasing attention. This review focused on systematically identifying and synthesizing evidence of longitudinal studies that evaluate different GHW formats and specifically considered GHW influence on perceived risk of tobacco use and quit intentions. METHODS: Ten databases were systematically searched for relevant records in December 2017 and again in September 2019. Thirty-five longitudinal studies were identified and analyzed in terms of the formatting of GHWs and the outcomes of perceived risk and quit intentions. Quality assessment of all studies was conducted. RESULTS: This review found graphics exceeding 50% of packs were the most common ratio for GHWs, and identified an ongoing reliance on negatively framed messages and limited source attribution. Perceived harms and quit intentions were increased by GHWs. However, wear-out effects were observed regardless of GHW format indicating the length of time warnings are present in market warrants ongoing research attention to identify wear out points. Quit intentions and perceived harm were also combined into a cognitive response measure, limiting the evaluation of the effects of each GHW format variables in those cases. In addition, alternative GHW package inserts were found to be a complimentary approach to traditional GHWs. CONCLUSIONS: This review demonstrated the role of GHWs on increasing quit intentions and perceptions of health risks by evaluating quality-assessed longitudinal research designs. The findings of this study recommend testing alternate GHW formats that communicate quit benefits and objective methodologies to extend beyond self-report. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12889-021-10810-z.