Tobacco industry denormalisation in children, adolescents, and parents in Hong Kong

Abstract

The tobacco industry (TI) has used various tactics to resist tobacco control policies. An intervention, known as tobacco industry denormalisation (TID), seeks to expose the misconducts of the TI. Research in the West has associated TID with desirable outcomes, e.g., smoking prevention. In non-Western settings, TID research is rare. This thesis aimed to explore TID’s potential effects and inform TID programme design in Hong Kong. In 2014/15, a territory-wide cross-sectional survey measured TID beliefs, meaning negative views of the TI, in Hong Kong secondary school students (mainly adolescents aged 12-17). In 2017/18, a pilot randomised controlled trial (RCT) of a smartphone messaging TID programme was conducted in Hong Kong primary school students (mainly children aged 6-11) and parents. A parent-student pair was eligible if they read Chinese and the parent used WhatsApp (a messaging application). Recruited pairs were randomised to receive 6 TID messages, or 4 messages on sugar-sweetened beverages (SSBs; as controls) through the parent’s WhatsApp over 1 month. Parents were asked to read the messages with students. Before the messaging programme, parents completed a questionnaire; when the programme ended, parents and students each completed a questionnaire. The primary outcomes were parents’ and students’ TID beliefs. Secondary outcomes included parents’ support for tobacco control policies, anti-tobacco communications from parents to students, etc. Associations of interest with binary and continuous outcomes were investigated using Poisson and linear regression, respectively. The territory-wide survey collected data from 14214 students. The levels of TID beliefs were inadequate: 22.5% considered the TI respectable; 43.4% believed that the TI did not try to get adolescents to smoke. TID beliefs were inversely associated with smoking susceptibility and behaviours, and positively associated with support for tobacco control policies. The association with policy support was stronger in current non-smokers than in current smokers. TID beliefs were generally not associated with quitting intention or attempts in current smokers. The associations of socio-economic status measurements and school-level smoking prevalence with TID beliefs either were non-significant or, when reached significance, did not follow meaningful patterns. The pilot RCT randomised 215 parent-student pairs to each group. Analyses were conducted in 84 and 107 parents and 68 and 89 students in the TID and SSB (control) groups, respectively. The TID programme was associated with strengthened TID beliefs in parents, but not associated with TID beliefs in students. The TID programme was associated with increases in parents’ support for tobacco control policies and anti-tobacco communications from parents to students. The parents and students rated the messages favourably, but more than one-third of the students reported they did not read all of the messages. Hong Kong adolescents were not adequately informed about the TI’s misconducts. If used in Hong Kong, TID may prevent adolescent smoking and increase public support for tobacco control policies. For TID in Hong Kong adolescents, general population approaches may be preferable to targeted approaches. In the smartphone-based TID programme, children’s exposure to the messages was less than intended. In parents, however, the programme was feasible, and associated with strengthened TID beliefs.