A randomized controlled trial of the effectiveness of combinations of ‘why to reduce’ and ‘how to reduce’ alcohol harm-reduction communications

Highlights

• Evidence on the efficacy of population-level alcohol control programs is needed.

• Combining ‘why to reduce’ intake with ‘how to reduce’ messages can be effective.

• Only some forms of ‘how to reduce’ messages appear to be effective.

• Encouraging drinkers to count their drinks can assist them reduce consumption.

Abstract

Introduction

Alcohol is a major source of harm worldwide. The aim of this study was to experimentally assess the effects of exposing Australian adult drinkers to combinations of ‘why to reduce’ and ‘how to reduce’ alcohol harm-reduction messages.

Methods

Three online surveys were administered over six weeks: Time 1 at baseline (n = 7,995), Time 2 at three weeks post-baseline (n = 4,588), and Time 3 at six weeks post-baseline (n = 2,687). Participants were randomly assigned to one of eight conditions: (1) a control condition; (2) a ‘why to reduce’ television advertisement; (3–5) one of three ‘how to reduce’ messages referring to the following protective behavioral strategies (PBSs): Keep count of your drinks, Decide how many drinks and stick to it, It’s okay to say no; and (6–8) the television advertisement combined with each PBS message individually. Intention-to-treat analyses were conducted to determine effects of condition assignment on changes over time in attempts to reduce alcohol consumption and amount of alcohol consumed.

Results

Participants assigned to the ‘TV ad’ and ‘TV ad + Keep count of your drinks PBS’ conditions reported significant increases in attempts to reduce alcohol consumption. Only participants assigned to the ‘TV ad + Keep count of your drinks PBS’ condition exhibited a significant reduction in alcohol consumed (−0.87 drinks per person per week).

Conclusions

Well-executed ‘why to reduce’ alcohol harm-reduction advertisements can encourage drinkers to attempt to reduce their alcohol consumption. These ads may be effectively supplemented by specific ‘how to reduce’ messages designed to encourage drinkers to monitor their intake.

Introduction

Alcohol consumption is a primary contributor to poor health globally, accounting for an estimated 7% of premature mortality (World Health Organization, 2018). Due to the extent of alcohol-related harms, the World Health Organization recommended in 2018 that Member States aim to achieve a minimum 10% reduction in harmful alcohol use by 2025 (World Health Organization, 2018).

A recommended strategy for reducing alcohol-related harms is the provision of consumer information about the adverse consequences of alcohol use (World Health Organization, 2017). While rated in terms of effectiveness behind other interventions that address the availability and affordability of alcohol (Anderson, Chisholm, & Fuhr, 2009), consumer education is needed for several reasons. First, a growing body of evidence documents the negative health effects of even moderate levels of consumption (Chikritzhs et al., 2015, Wood et al., 2018, Zhao et al., 2017), yet many drinkers are unaware of these health risks. For example, surveys in the UK, Australia, and Canada have found that only between a quarter and half of people report being aware that alcohol is a carcinogen and therefore potentially risky at any level of consumption (Hydes et al., 2020, Vallance et al., 2020, Pettigrew et al., 2016). The public has a fundamental right to know about the adverse health effects attributable to a commonly consumed product that is widely available in their communities (Burton et al., 2017, Wilkinson and Room, 2009). Second, an understanding of alcohol-related harms is likely to increase community receptivity to the introduction of more stringent policy measures (Anderson et al., 2009, Christensen et al., 2019).

Third, there is strong public support for consumer education campaigns (Dekker, Jones, Maulik, & Pettigrew, 2020), making this among the less contentious investments in alcohol harm reduction. Similarly, the alcohol industry tends to be less resistant to these kinds of initiatives, resulting in less of the intense government lobbying that occurs against other proposed interventions (Stafford, Kypri, & Pettigrew, 2020). Finally, health-related information is needed to provide some offset against the billion-dollar alcohol advertising industry that supports global product sales of more than US$1.5 trillion (Jernigan & Ross, 2020). Alcohol products are advertised about three times more frequently than other products (Saffer, 2020), and typically depict alcohol consumption as safe, pleasurable, and socially acceptable (Morgenstern et al., 2017, Pettigrew et al., 2012, Pettigrew et al., 2020).

Consumer information about alcohol can be disseminated in various ways, including product labelling, school curricula, and social marketing campaigns (Burton et al., 2017). The focus of the present study is on two different messaging approaches adopted within the social marketing category of action: communications featuring ‘why to reduce’ messages and those featuring ‘how to reduce’ messages (Duke, Nonnemaker, Davis, Watson, & Farrelly, 2014). Frameworks such as the Reasoned Action Approach (Fishbein & Ajzen, 2011) and the Extended Parallel Process Model (Witte, 1992) highlight the importance of ensuring target audiences have both knowledge of why behavior change is desirable and an understanding of how they can achieve the recommended behavior change. Evidence from the tobacco control field indicates that campaigns featuring ‘why to quit’ messages are more effective than ‘how to quit’ messages in encouraging cessation, including among those with weaker quit intentions (Duke et al., 2014, Durkin et al., 2012, Nonnemaker et al., 2013). Similarly, preliminary work undertaken in alcohol harm-reduction has found that ‘why to reduce’ messages were more likely than ‘how to reduce’ messages to be rated as motivating by drinkers (Wakefield et al., 2017). There is also evidence that within the ‘why’ category of messages, those that emphasize the adverse health effects of smoking and alcohol using a negative emotional tone are more effective than those using other executional approaches (Durkin et al., 2012, Durkin et al., 2018, Wakefield et al., 2017, Niederdeppe et al., 2016, Nonnemaker et al., 2014, Sims et al., 2016).

The consistency in findings relating to the superiority of ‘why’ messages is reflected in a majority of alcohol harm-reduction advertisements in a large international sample being found to use this approach (Dunstone et al., 2017). However, there has been a tendency for past research testing the relative effectiveness of why and how messages to focus on television advertisements that use just one of these approaches, and there appears to be a lack of work assessing the relative efficacy of combining both why and how messages within broader social marketing campaigns comprising television advertisements and other forms of communication.

A potential complement to ‘why to reduce’ advertisements are communications relating to protective behavioral strategies (PBSs). PBSs are approaches used by drinkers to attempt to reduce their alcohol intake and/or any associated harms (Richards et al., 2018). Communications encouraging PBS use thus represent ‘how to reduce’ messages. PBSs include actions such as eating while drinking, quenching thirst with a non-alcoholic drink prior to consuming alcohol, alternating between alcoholic and non-alcoholic beverages, setting drinking limits, and avoiding drinking games (Treloar et al., 2015, Martens et al., 2005). Most prior PBS research has examined PBS use among college students and young adults (Blanchard et al., 2018, Blanchard et al., 2019, Bravo et al., 2018, Fairlie et al., 2020, Madden and Clapp, 2019, Linden-Carmichael et al., 2018, Martens et al., 2011, Miller et al., 2019, Montes et al., 2019, Hembroff et al., 2019, Grazioli et al., 2015, Grazioli et al., 2018, Voss et al., 2018). Some of this work has assessed the effectiveness of college-based interventions designed to reduce alcohol-related harms by encouraging students to use PBSs, and has therefore focused on forms of communication other than mass media (Dvorak et al., 2015, LaBrie et al., 2015, Leavens et al., 2020, Leeman et al., 2016, Kenney et al., 2014). This body of research has yielded mixed outcomes in terms of the ability of various approaches to promoting PBSs to produce reductions in alcohol consumption. Similarly, the limited research examining PBS use in general population samples suggests that some, but not all, PBSs may assist drinkers to achieve alcohol intake reductions (Dekker et al., 2020, Drane et al., 2019, Jongenelis et al., 2016). This work indicates that the most effective PBSs for adults are likely to be those involving drink counting, setting drinking limits, refusing unwanted drinks, drinking slowly, and avoiding trying to keep up with or outdrink others. There may therefore be the potential to increase the overall effectiveness of alcohol harm-reduction efforts by promoting specific PBSs as ‘how to reduce’ messages to accompany the ‘why to reduce’ messages more commonly disseminated via the mass media.

The study aim was to longitudinally test the ability of an alcohol harm-reduction television advertisement, messages communicating various PBSs, and combinations thereof to influence drinkers’ alcohol-related behaviors. The study context was Australia, where per capita alcohol consumption appears to be decreasing over time but remains high at 9.5 L of pure alcohol per year (Australian Bureau of Statistics, 2019). Australia rates relatively poorly on the Alcohol Control Policy Index, receiving a score of 47.7 out of 100 (Madureira-Lima & Galea, 2018). National alcohol harm-reduction campaigns have been largely lacking to date, with the partial exception of drink driving campaigns. However, some state governments have invested in media campaigns to advise drinkers of the various harms associated with alcohol consumption. An example is the Western Australian Government’s Spread ad that informs drinkers that alcohol use increases their risk of cancer (Dunstone et al., 2017) (available at https://alcoholthinkagain.com.au/campaigns/alcohol-and-health-spread). This ad was found to be the most effective out of a total sample of 83 ads from around the world in making drinkers’ feel motivated to reduce their intake (Wakefield et al., 2017), and was thus selected for use in the present study along with three PBSs found to be potentially effective among Australian drinkers: ‘Keep count of your drinks’, ‘Decide how many drinks and stick to it’, and ‘It’s okay to say no if you’re offered a drink’ (Drane et al., 2019, Dekker et al., 2018).