Background One-third of the burden of cancer is associated with four health harming behaviours – tobacco use, alcohol consumption, poor diet and physical inactivity. These individual behaviours are influenced by a complex array of socio-political factors, including industry interests. The growing evidence base supporting the use of price-related policies to curb over consumption of unhealthy products is of interest to governments around the world. However, the implementation of such policies requires public and policy-maker support. The aim of this study is to enhance our understanding of the features of message framing that influence public support in relation to four price-related policies (1-tax, 2-mitigation fee, 3-discounting ban and 4-minimum pricing); across three products (tobacco, alcohol and sugar); and two countries (USA and UK).

Methods We conducted 18 semi-structured interviews exploring knowledge, attitudes, and beliefs of the four pricing policies in relation to tobacco, alcohol and sugar products in 2018. Nine in the USA and nine in the UK. Interviewees included cancer policy advocates, cancer survivors and members of the general public. NVivo 12 was used to organise the data for inductive and deductive thematic analysis.

Results Common supportive features across all four policies included (i) highlighting the health benefit (including reduced cancer risk), particularly for young people and those on low income, arising from impact on purchasing behaviour and (ii) making the cost of consumption in terms of health harm clear. Common unsupportive features across policies included (i) that effectiveness will depend on size of the financial penalty and consumer response and (ii) such policies are unfair on sensible consumers and potentially regressive. Interviewees’ were more supportive of price-related policies for tobacco containing products where they perceived a strong association between tobacco use and cancer risk. Some differences in views arose between products, particularly around the addictive nature of alcohol and tobacco that did not apply to sugar consumption.

Conclusion This study reveals important differences in levels of persuasiveness arising from the framing of messages designed to promote price-related policies as a health promotion strategy. The results have informed the identification of four frames to be tested in a multi-factorial quantitative study, currently under way. These frames can be characterised as: F1 - To reduce the financial strain on the health care system; F2 - For the protection of children and young people; F3 - To reduce cancer risk; and F4 - To reduce the risk of other non-communicable diseases.