Application of Discrete-Choice Experiment Methods in Tobacco Control: A Systematic Review

Preferences for couple-based smoking cessation interventions among couples who smoke: online discrete choice experiment

The purpose of this study was to elicit smoking couples' preferences for the 'format' and 'content' of couple-based interventions and partner support from both partners' perspectives, using an online discrete choice experiment (DCE) survey. An online DCE study was conducted during online interviews with 56 smoking couples (N = 112). Conditional logistic regression models were constructed to determine optimal profiles of couple-based treatment. Six attributes of couple-based smoking cessation interventions were identified as statistically significant: smokers and their partners preferred interventions that were designed for both partners, interactive, and tailored; they also valued positive support, open discussions with their partners, and having their partners involved in the quitting process. Smokers preferred to receive empathy, love, and trust from their partners rather than information, advice, and services. Income level and race interacted with the preferences for certain attributes. Differences in convenience, method of delivery, topics, duration, and frequency of treatment, willingness to provide support, frequency of partner support, and couple types were not significant. This study highlights the significance of incorporating partner involvement and support in smoking cessation interventions. The findings can provide direction for developing efficient couple-based interventions that consider the preferences of both smokers and partners.

The impacts of product characteristics and regulatory environment on smokers' preferences for tobacco and alcohol: Evidence from a volumetric choice experiment

OBJECTIVE

Concurrent use of alcohol and cigarettes is well-documented in the literature. However, it is unclear how e-cigarette regulations in a growing number of localities impact the use of tobacco and alcohol in the US. This study aims to evaluate the impacts of excise taxes, tobacco use restrictions in restaurants/bars, and availability of alcohol flavor in e-cigarettes on tobacco consumption, and their cross impacts on alcohol consumption.

METHOD

A total of 181 US adult smokers who were using e-cigarettes and consuming alcohol participated in online volumetric choice experiments and reported on the quantity they would purchase among cigarettes, closed-system e-cigarettes, beer, and one other alcohol product (wine/liquor) under varying policy scenarios.

RESULTS

Estimated own-price elasticities of demand for beer, liquor/wine, and cigarettes were -0.10, -0.11, and -0.16, respectively (p <  0.001). Higher beer (cross-price elasticity =  0.13) and liquor/wine prices (cross-price elasticity =  0.05) increased e-cigarette consumption (p <  0.05). If e-cigarettes were allowed in bars/restaurants, their consumption increased by 2.4 units (p <  0.001), and if cigarettes were allowed in bars/restaurants, e-cigarette consumption increased by 1.9 units (p <  0.01), relative to the mean consumption level. Greater reported weekly spending on alcohol and/or tobacco was associated with higher consumption of all products (p <  0.001).

CONCLUSIONS

Higher taxes or prices may reduce the consumption of beer, liquor/wine, and cigarettes. E-cigarettes are economic substitutes for alcohol among smokers who are currently drinking and using e-cigarettes. Regulating tobacco indoor use will have an impact on e-cigarette consumption.

Development of an online discrete choice experiment to elicit preferences for tobacco treatment among college students

OBJECTIVE

To develop an online discrete choice experiment (DCE) to elicit preferences for the format and content of tobacco treatment and determine the feasibility of the survey in face-to-face online interviews among college students.

PARTICIPANTS

A convenience sample of 28 college students.

METHODS

A pilot online DCE survey with sixteen choice sets was developed. The feasibility was assessed by: 1) ease of reading the survey descriptions, 2) ease of completing the DCE survey, and 3) appropriateness of the number of choice sets. Think-aloud data were analyzed to understand decision-making processes.

RESULTS

All participants completed the DCE survey and reported that it was very easy to read and complete and that the number of sixteen choice sets was appropriate. Such results support the feasibility of our online DCE survey. Five decision-making strategies were identified.

CONCLUSIONS

An online DCE survey administered during online interviews may replace in-person interviews for college students.

Effects of cigarette price and packaging on hypothetical quit-smoking behaviour: a discrete choice experiment among Vietnamese adults who smoke

INTRODUCTION

Raising cigarette prices, increasing graphic health warning label (HWL) coverage and requiring plain packaging could reduce cigarette smoking in Vietnam. This discrete choice experiment estimates the potential impact of these policies on smoking behaviour.

METHODS

In February-May 2022, we conducted a phone-based, cross-sectional survey of 1494 Vietnamese adults who smoke. Participants were randomly assigned to view four individual cigarette pack images, varied on price (15 000 (reference group); 20 000; 30 000 or 40 000 Vietnamese dong (VND)) and packaging (branded pack with 50% graphic HWL (reference group); branded pack with 85% graphic HWL; plain pack with 50% graphic HWL or branded pack without HWL). Participants responded if they would quit or continue smoking if they could only purchase the pack shown. We used binomial logistic regressions to estimate the relative risk (RR) of price and packaging on hypothetical quitting.

RESULTS

Participants were more likely to report they would quit when presented with 30 000 VND (RR 1.20, 95% CI 1.07 to 1.35) and 40 000 VND packs (RR 1.40, 95% CI 1.23 to 1.58) vs the 15 000 VND pack. Participants were also more likely to report they would quit when shown the branded pack with 85% HWL (RR 1.30, 95% CI 1.18 to 1.42) and plain pack with 50% HWL (RR 1.34, 95% CI 1.21 to 1.49) vs the branded pack with 50% HWL coverage. Participants had significantly lower quit likelihood (RR 0.41, 95% CI 0.35 to 0.48) when shown the branded pack without a HWL.

CONCLUSIONS

Results suggest raising cigarette prices to at least 30 000 VND, implementing larger graphic HWLs or plain packaging could decrease smoking rates in Vietnam.

Identifying attributes of effective cigar warnings: a choice-based conjoint experiment in an online survey of US adults who smoke cigars

OBJECTIVE

Little evidence exists on which cigar warning statement attributes may impact cigar warning effectiveness; research is needed to identify the most effective cigar warning topics and text. This study was designed to inform the development of improved cigar warnings.

DESIGN

We conducted a choice-based conjoint experiment. The experiment systematically manipulated cigar warning statement attributes, including cancer health effect (mention of colon cancer and/or oral cancer), non-cancer health effect (mention of heart disease and/or blood clots), causal language, warning marker word, verb use and tobacco type. Participants evaluated eight choice sets, each containing three cigar warnings with contrasting attributes, and chose the warnings that most and least encouraged them to quit smoking cigars. Using a Bayesian mixed logit model, we estimated the relative importance of each attribute and the attribute part-worth utility.

SETTING

An online survey of adults in the USA.

PARTICIPANTS

We enrolled 959 US adults who used little cigars, cigarillos, or large cigars in the past 30 days using an online survey from October to December 2020.

PRIMARY OUTCOME MEASURES

The primary outcomes for the experiment are relative attribute importance and attribute part-worth utility.

RESULTS

The most important attributes to participant selection of warnings were the non-cancer and the cancer health effects (29.3%; 95%CI 28.6% to 30.0% and 29.0%; 95% CI 28.4% to 29.6%, respectively), followed by causal language (16.3%; 95% CI 15.7% to 16.8%), marker word (10.3%; 95% CI 9.9% to 10.7%), verb use (8.8%; 95% CI 8.5% to 9.2%) and tobacco type (6.3%, 95% CI 5.9% to 6.6%).

CONCLUSIONS

Our findings indicate that health effects are the most important attributes when designing cigar warning statements, but other attributes, like causal terminology, also influence perceived warning effectiveness. Based on our findings, 'DANGER: Tobacco causes heart disease and blood clots' is an example of a highly effective warning statement for cigars.

Discrete Choice Experiment on Financial Incentives for Engaging Young Adults in Vaping Cessation Programs

INTRODUCTION

Contingency management involves rewarding individuals based on objective evidence of behavioral changes. This study explores preferences for financial incentives in vaping cessation programs.

METHODS

A discrete choice experiment (DCE) was conducted among young adult current e-cigarette users aged 19-29. DCE attributes (and levels) included reward amount ($100, $300), reward schedule (consistent value, escalating value), reward procedure (gain-framed, loss-framed), vaping education modules (yes, no), text messaging support (yes, no), and cost ($30, $100). Participants were randomized into one of the four blocks, each containing four choice sets. Each choice set presented two hypothetical vaping cessation programs. Choice data (n × choice sets × alternative programs = 154 × 4 × 2 = 1,232 observations) were analyzed using generalized estimation equation models.

RESULTS

Participants showed a preference for vaping cessation programs offering a higher reward amount (odds ratio [OR] = 11.5; 95% CI,7.0-19.2), gain-framed rewards for sustained abstinence (OR = 1.4; 95% CI,1.0-1.8), text messaging support (OR = 1.9; 95% CI,1.4-2.5), and a lower program cost (OR = 2.6; 95% CI,1.8-3.8). Interaction tests showed significant effects of the rewards procedure among daily e-cigarette users (adjusted OR [AOR] = 2.1; 95% CI,1.3-3.5), but not some-day users; and among those with no quit attempts in the past six months (AOR = 2.7; 95% CI,1.5-4.7), but not those with previous quit attempts. Female participants preferred text messaging support (AOR = 3.6; 95% CI,2.3-5.4), whereas male participants did not show this preference.

CONCLUSION

A multifaceted vaping cessation intervention augmented with financial incentives might improve participation and engagement among young adults. Future studies should investigate how these attributes can enhance program reach and vaping abstinence outcomes in real-world settings.

Cannabis consumers' preferences for legal and illegal cannabis: evidence from a discrete choice experiment

BACKGROUND

In U.S. states that legalized and commercialized recreational cannabis, cannabis sales in illegal markets are still sizable or even larger than those in legal markets. This study aimed to assess cannabis consumers' preferences for purchasing cannabis from legal and illegal markets and estimate the trade-offs under various policy scenarios.

METHODS

963 adults were recruited, who used cannabis in the past year and lived in a state with recreational cannabis legalization. In a discrete choice experiment, participants chose purchasing cannabis from a legal dispensary or an illegal dealer with varying levels in product attributes including quality, safety, accessibility, potency, and price. Mixed logit models were used to analyze preferences.

RESULTS

The likelihood of choosing legal cannabis increased with a higher quality, the presence of lab test, a shorter distance to seller, a higher tetrahydrocannabinol level, and a lower price. The likelihood of choosing illegal cannabis increased with a higher quality, a shorter distance to seller, and a lower price. Among product attributes, quality and accessibility were perceived to be the most important for legal cannabis and price was perceived to be the most important for illegal cannabis. Policy simulations predicted that improving quality, ensuring safety, allowing delivery services, increasing dispensary density, and lowering prices/taxes of legal cannabis may reduce illegal cannabis market share.

CONCLUSIONS

In the U.S., cannabis consumers' preferences for illegal cannabis were associated with both legal and illegal cannabis product attributes. Policies regulating legal cannabis markets should consider potential spillover effects to illegal markets.

Would plain packaging and health warning labels reduce smoking in the presence of informal markets? A choice experiment in Colombia

BACKGROUND

Despite progress made by many countries on the adoption of plain tobacco packaging laws over the last years, low- and middle-income countries, with a large supply of loose cigarettes via informal vendors, remain far behind.

AIM

To study the potential effectiveness of plain tobacco packaging and dissuasive cigarette sticks, via willingness-to-pay estimates, when illicit cigarette options are available.

METHODS

We conducted a discrete choice experiment (DCE) in which respondents chose licit and illicit products with three attributes: packaging (standard vs. plain packaging), stick design (branded stick vs. stick with warning), and price level. The sample, collected on 12/2021, consisted of 1761 respondents from an internet panel involving smokers and nonsmokers. Conditional logit and latent class models were used to estimate the willingness-to-pay (WTP) to avoid restrictive packaging elements.

RESULTS

Nonsmokers are willing to pay USD $5.63 for a pack of cigarettes to avoid plain packaging, which is higher than the actual commercial price of illicit cigarettes (USD $2.40). The WTP increases to USD $12.14 in the presence of illicit alternatives. Smokers are also willing to pay to avoid illicit options, which they also deem riskier, and the presence of such options increases the WTP to avoid plain packaging. However, nonsmokers do not perceive the illicit option as riskier. The dissuasive stick (stick with warning) does not affect perceptions of risk and plays a small role in terms of choice for both smokers and nonsmokers.

CONCLUSIONS

Even in the presence of illicit tobacco alternatives, plain packaging seems to be as effective in reducing the attractiveness of tobacco products in Colombia as in other countries that have already adopted it. Given conflicting results on the case for dissuasive sticks, there is a need for more research.

How should regulatory schemes be optimized to enhance deterrence against medical insurance fraud by enrollees? Evidence from a discrete choice experiment in China

Medical insurance fraud (MIF) poses a substantial global financial challenge, necessitating effective regulatory strategies, especially in China, where such measures are in a critical developmental phase. This study investigates the effectiveness of various regulatory components in deterring MIF among enrollees and explores preference heterogeneity among individuals with different characteristics, utilizing a discrete choice experiment survey. Grounded in deterrence theory, our conceptual framework incorporates five attributes: intensity of economic penalties, restrictions on medical insurance benefits, deterioration of social reputation, and certainty and celerity of penalties. Employing a D-efficiency design, 24 choice sets were generated and blocked into three versions. A multistage stratified sampling method was adopted to collect data from the basic medical insurance enrollees in Shanghai. The survey was conducted from September to October 2022. The sample representativeness was further improved via the entropy balancing approach. Data from the final sample of 1034 respondents were analyzed using mixed logit models (MIXLs), incorporating interactions with individual characteristics to assess preference heterogeneity. Results reveal that escalating economic penalties, suspending insurance benefits, listing individuals as unfaithful parties, ensuring penalty certainty, and expediting enforcement significantly enhance the deterrent effect. We observed preference heterogeneity across different demographics, including age, gender, education, health status, and employment status. The study underscores the pivotal role of economic penalties in deterring MIF, while also acknowledging the significance of non-economic measures such as enforcement efficiency and social sanctions. These findings offer valuable insights for policymakers to tailor and strengthen regulatory schemes against MIF, contributing to the advancement of more effective and precise healthcare policies.

The impacts of packaging on preferences for cannabis edibles: A discrete choice experiment

BACKGROUNDS

Cannabis edibles recently gained considerable market share in the United States. The tobacco and food literatures consistently suggest that product packaging regulations are crucial to substance control, but little is known about how product packaging may impact cannabis edible use. This study aims to estimate the impacts of packaging on individual preferences for cannabis edibles and explore heterogeneities in preferences by cannabis use status and use purposes.

METHODS

1578 adults were recruited, who lived in 18 states and Washington D.C. in the United States that legalized recreational cannabis by the time of data collection in August and September of 2022. An online discrete choice experiment was conducted to elicit individual choices between cannabis edibles with variations in five packaging attributes: package style, health claim, potency indicator, warning label position, and warning label text. Mixed logit regressions were used to assess associations between package attributes and package choices. Subsample analysis was conducted by cannabis use status (users vs. nonusers) and use purposes (medical-only, recreational-only, and dual-purpose) to detect heterogeneities.

RESULTS

Almost all subsamples prefer branded packages to plain packages, any health claim to no health claim, and any potency indicator to no potency indicator. Cannabis users, particularly recreational-only users and dual-purpose users, also prefer youth-appealing packages to branded packages. Warning label position and text have limited impacts on choices. Overall, package style is perceived to be the most important attribute among the five (relative importance 33.2-50.8%), followed by health claim (relative importance 22.6-30.5%).

CONCLUSION

In the United States, adults' preferences for cannabis edibles are associated with packaging features. Policies requiring plain package and prohibiting youth-appealing package and unsubstantiated health claims may be effective methods of cannabis control.

Assessing the job preferences of senior medical students for mandatory service: a discrete choice experiment

AIM

To investigate the job preferences of senior medical students for mandatory service as general practitioners using discrete choice experiment.

INTRODUCTION

Health workforce is directly associated with health service coverage and health outcomes. However, there is a global shortage of healthcare workers (HCWs) in rural areas. Discrete choice experiments can guide the policy and decision-makers to increase recruitment and retention of HCWs in remote and rural areas by determining their job preferences. The aim of this study is to investigate job preferences of senior medical students for mandatory service as general practitioners.

METHODS

This cross-sectional survey was conducted among 144 medical students. To estimate students' preferences for different levels of job attributes, a mixed logit model was utilised. Simulations of job uptake rates and willingness to pay (WTP) estimates were computed.

FINDINGS

All attributes had an impact on the job preferences of students with the following order of priority: salary, workload, proximity to family/friends, working environment, facility and developmental status. For a normal workload and a workplace closed to family/friends which were the most valued attributes after salary, WTPs were 2818.8 Turkish lira (TRY) ($398.7) and 2287.5 TRY ($323.6), respectively. The preference weights of various job characteristics were modified by gender, the presence of a HCW parent and willingness to perform mandatory service. To recruit young physicians where they are most needed, monetary incentives appear to be the most efficient intervention. Non-pecuniary job characteristics also affected job preferences. Packages of both monetary and non-monetary incentives tailored to individual characteristics would be the most efficient approach.

Messaging about very low nicotine cigarettes (VLNCs) to influence policy attitudes, harm perceptions and smoking motivations: a discrete choice experiment

BACKGROUND

To reduce smoking and the harms it causes, countries, including the USA, are considering policies to reduce nicotine in combustible tobacco to minimally addictive levels. Effective messages about very low nicotine cigarettes (VLNCs) and this policy are crucial in combating misperceptions threatening the policy's effectiveness.

DATA AND METHODS

A discrete choice experiment assessed messages about VLNCs. Participants were 590 adults who smoked exclusively, 379 adults who both smoked and used e-cigarettes, 443 adults who formerly smoked and 351 young adults who never smoked (total n=1763). Seven message attributes were varied systematically (source, harm, chemicals, nicotine, satisfaction, addictiveness and quitting efficacy). Outcomes were selection of messages that generated the most positive attitude towards reduced nicotine policy, the greatest perceived harmfulness of VLNCs, and most strongly motivated quitting and initiating behaviour for VLNCs.

RESULTS

Information about specific harms and chemicals of VLNCs had the largest effects on selection of messages as eliciting more negative attitudes towards VLNCs policy, increasing perceived VLNC harmfulness, increasing motivation to quit VLNCs and decreasing motivation to try VLNCs. Messages with information about quitting efficacy were selected as more motivating to quit among those who smoke, but also more motivating to try VLNCs among those who do not smoke.

CONCLUSION

Harm and chemical information can be prioritised to ensure VLNCs are not misperceived as less harmful than regular cigarettes. Messages about increased quitting efficacy and reduced addictiveness associated with VLNCs may backfire if presented to those who do not smoke.

Tobacco minimum packaging policy to reduce cigarillo use among young people: results of an experimental study

OBJECTIVE

The Food and Drug Administration has the authority to set a minimum for cigar pack size, a product feature linked to price. This study examined the effects of cigarillo package size and price on young adults' smoking and purchase intentions.

DESIGN

Young adults (n=1032) 18-30 years old who smoked cigarillos in the past 12 months completed an online 3×2 within-subjects experiment testing the effects of cigarillo pack size (1, 2, 5) and price (actual price, standardised price per stick) on intentions to purchase and smoke cigarillos. We modelled the main effects and interactions of pack size and price on intentions to buy and smoke cigarillos overall and by cigarillo use frequency.

RESULTS

Intentions to buy and smoke were strongest for lower priced singles and two packs compared with higher priced five packs. Under standardised price conditions, participants preferred larger packs, but under actual pricing conditions smaller packs, especially two packs, were preferred. Participants who smoked cigarillos less than monthly were more likely to buy and smoke the least expensive products (buy: singles actual price adjusted OR (aOR)=4.51, 95% CI 3.76 to 5.42; two packs actual price aOR=9.76, 95% CI 8.11 to 11.75; five packs standardised price aOR=3.17, 95% CI 2.89 to 3.48) with the strongest preference for two packs and singles.

CONCLUSIONS

Young adult cigarillo smokers prefer smaller packs in conditions where pricing incentivises smaller packs. Minimum pack size policies may reduce the appeal of cigarillos among young adults, especially less frequent cigarillo smokers. Pack size policy should take into consideration price, and ideally these two factors should be addressed together.

College students' preferences for tobacco treatment: a discrete choice experiment

The purpose of this study was to elicit preferences for the 'format' and 'content' of tobacco treatment among college student smokers, using an online discrete choice experiment (DCE) survey. A DCE survey, supplemented with a think-aloud method, was conducted among 54 college students who smoked combustible cigarettes and/or e-cigarettes. Conditional logistic regression models were constructed to determine optimal profiles of treatment. Cutting down nicotine rather than quitting 'cold turkey' (P < 0.001) and two-way communication (P < 0.001) were viewed as the most critical attributes for the intervention 'format'; changing behaviors rather than social groups/peers (P < 0.001) and autonomy (P < 0.001) were viewed as the most critical attributes for the intervention 'content'. Some preferences varied based on smoking subgroups. Combustible cigarette users preferred interventions with a longer time commitment (P < 0.05) and without nicotine replacement therapies (NRTs) (P < 0.001). Think-aloud data supported the DCE findings and further revealed a strong desire for cutting down nicotine and keeping social groups/peers and misconceptions regarding NRTs. Our study findings can guide tobacco treatment tailored to college students. These treatments should be tailored to specific smoker subgroups.

Effects of reduced nicotine content cigarette advertising with warning labels and social media features on product perceptions among young adults

This study sought to understand reactions to very low nicotine (VLN) cigarette advertising compared with conventional cigarette advertising with consideration of warning labels and social media context. The online experimental study recruited young adult cigarette smokers and nonsmokers (N = 1,608). Participants completed a discrete choice task with a 2 × 2 × 3 mixed design: brand, (VLN, Marlboro), context (Ad only, Ad on social media), and warning (Text-only, Well-known risk pictorial, or Lesser-known risk pictorial). Participants made choices about attention, appeal, harm, buying, and quitting intentions. Social media context increased attention and appeal. A well-known risk pictorial warning outperformed a text-only warning. Smokers had increased odds of quit intentions for VLN ads, yet nonsmokers had increased intentions to buy cigarettes on social media with a text-only warning. Results indicate differences in how young adults react to cigarette ads on social media, especially with the warnings they portray.

Will tobacco price increases lead more people who smoke to vape? The results from a discrete choice experiment amongst U.S. adults

OBJECTIVE

To understand the extent to which people who smoke, people who vape and nonsmokers would switch between smoking cigarettes and vaping in response to policies (price increases, restrictions on nicotine, places, and information on addictiveness and/or health risks) aimed at decreasing tobacco use by people who smoke and vaping by nonsmokers.

DESIGN

A total of 525 adults aged 18 to 88 years completed a discrete choice survey of 16 choices between two smoking/vaping alternatives. Analysis was conducted using conditional logistic regression for the entire sample and stratified by nonsmokers, people who smoke, and people who vape.

RESULTS

The results suggest that most people who vape also smoke. Nonsmokers were more favorable to vaping and were concerned about long-term health risks and cost associated with vaping. Marginal analysis suggests that price increases will have only modest success in moving people who smoke to start vaping or encouraging people who vape to vape rather than use cigarettes. Nonsmokers are not very sensitive to price changes but are sensitive to information about health impacts.

CONCLUSIONS

Findings indicate that increasing the price of cigarettes would lead to a limited increase in the probability of people who smoke switch to vaping. The study advances our understanding of the views of current nonsmokers toward cigarettes and vaping, suggesting that price increases and increased knowledge of addiction would likely deter nonsmokers from vaping. Changing the amount of nicotine associated with smoking would increase the probability of vaping slightly and have little impact on nonsmokers or vaping preferences, but the most significant change would come from increasing the perceptions of the risk of smoking.

Harm reduction for smokers with little to no quit interest: can tobacco policies encourage switching to e-cigarettes?

OBJECTIVE

A pressing tobacco policy concern is how to help smokers who have little interest in quitting cigarettes, a group that often suffers severe health consequences. By switching from cigarettes to e-cigarettes, they could obtain nicotine, potentially with less harm. We examined if policy-relevant attributes of cigarettes/e-cigarettes might encourage these smokers to switch to e-cigarettes.

METHODS

An online survey and discrete choice experiment on a nationally-representative sample of adult smokers in the US who reported low interest in quitting (n=2000). We modelled preference heterogeneity using a latent class, latent variable model. We simulated policies that could encourage switching to e-cigarettes.

RESULTS

Participants formed two latent classes: (1) those with very strong preferences for their own cigarettes; and (2) those whose choices were more responsive to policies. The latter group's choices were only somewhat responsive to menthol cigarette bans and taxes; the former group's choices were unresponsive.

CONCLUSIONS

The policies studied seem unlikely to encourage harm reduction for individuals with little interest in quitting smoking.

Impact of flavours, device, nicotine levels and price on adult e-cigarette users' tobacco and nicotine product choices

INTRODUCTION

To understand the impact of e-cigarette devices, flavours, nicotine levels and prices on adult e-cigarette users' choices among closed-system and open-system e-cigarettes, cigarettes and heated tobacco products (HTPs).

METHODS

Online discrete choice experiments were conducted among adult (≥18 years) e-cigarette users (n=2642) in August 2020. Conditional logit regressions were used to assess the relative impact of product attributes and the interactions between product attributes and user characteristics, with stratified analyses to examine differences by smoking status and primarily used e-cigarette device and flavour.

RESULTS

On average, participants preferred non-tobacco and non-menthol flavours most, preferred open-system over closed-system e-cigarettes and preferred regular nicotine level over low nicotine level. However, the preference varied by demographics, smoking status and the primarily used e-cigarette device and flavour. The differences in preference among products/devices were larger than the difference among flavours or nicotine levels. Participants who primarily used closed-system e-cigarettes exhibited similar preferences for closed-system and open-system e-cigarettes, but those who primarily used open-system e-cigarettes preferred much more open-system over closed-system e-cigarettes. HTP was the least preferred product, much lower than cigarettes in general, but participants living in states where IQOS is being sold had similar preferences to cigarettes and HTPs.

CONCLUSIONS

People are unlikely to switch to another product/device because of the restriction of flavour or nicotine level. If non-tobacco and non-menthol flavours were banned from open-system e-cigarettes, users may switch to menthol flavour e-cigarettes. Intervention strategies should be tailored to specific groups.

A discrete choice experiment on price and flavour effects on the appeal of nicotine products: a pilot study among young adults in Switzerland

AIMS

To explore the effects of prices and flavour availability on the appeal of different tobacco and nicotine products, including conventional cigarettes, Electronic Nicotine Delivery Systems (ENDS) and Heated Tobacco Systems (HTS) among an adult population in Switzerland.

METHODS

We performed a Discrete Choice Experiment among a group of Swiss aged ≥18 years via the online recruiting platform Prolific in a convenience sample. Our sample included both non-smokers and smokers. We used a within-subject, alternative-specific block design in a series of choice sets including different smoking products. We fixed the attributes of nicotine content (high or medium) and harmfulness (in years of life lost) for each product. Attributes of interest included price (ranging from CHF 5 to 25 in increments of 5) and flavour (fruity/menthol vs none/tobacco flavour). We performed a conditional logistic regression on the attributes' influence on the appeal of cigarettes, ENDS and HTS.

RESULTS

A total of 108 out of 153 participants (n = 25 smokers and n = 83 non-smokers, completion rate = 71%) successfully completed our pilot survey experiment. We found that, in general, increasing the price of combustible cigarettes, ENDS and HTS by one standard deviation (around CHF 7) reduced their appeal by approximately 66% (relative risk [RR]: 0.34; 95% CI: 0.28-0.42). Unflavoured alternative nicotine products were found to be less appealing than flavoured products, especially for non-smokers, with a 86% decrease in appeal (RR: 0.14; 95% CI: 0.13-0.16). For non-smokers, an increase in price by one standard deviation was associated with a decrease in the appeal of any product by approximately 19% (RR: 0.81; 95% CI: 0.72-0.92). For smokers, the effect sizes were smaller, but overall, the appeal of all products decreased with increasing prices and reduced flavours.

CONCLUSIONS

Our Discrete Choice Experiment suggests that, for the Swiss context, limiting the availability of flavours for alternative smoking products has the potential to reduce their appeal to non-smokers by 86% and that a small but significant increase in prices to CHF 15 for cigarettes, ENDS and HTS could lead to a major (around 66%) decrease in their appeal.

Own-price and cross-price elasticities of demand for cigarettes and waterpipe tobacco in three Eastern Mediterranean countries: a volumetric choice experiment

BACKGROUND

Waterpipe tobacco smoking rates in the Eastern Mediterranean region are among the highest worldwide, yet little evidence exists on its economics. Estimates of demand elasticities for tobacco products are largely limited to cigarettes. This study aimed to estimate own-price and cross-price elasticities of demand for cigarettes and waterpipe tobacco products in Lebanon, Jordan and Palestine.

METHODS

A volumetric choice experiment was conducted using nationally representative household surveys. The choice experiment elicited respondents' stated purchases of eight cigarette and waterpipe tobacco product varieties by hypothetically varying prices. Data were analysed using zero-inflated Poisson models that yielded demand elasticity estimates of cigarette and waterpipe tobacco consumption.

RESULTS

The study included 1680 participants in Lebanon (50% female), 1925 in Jordan (44.6% female) and 1679 in Palestine (50% female). We found the demand for premium cigarettes to be price elastic (range, -1.0 to -1.2) across all three countries, whereas the demand for discount cigarettes was less elastic than premium cigarettes in Lebanon (-0.6) and Jordan (-0.7) and more elastic in Palestine (-1.2). The demand for premium waterpipe tobacco was highly elastic in Lebanon (-1.9), moderately elastic in Jordan (-0.6) and inelastic in Palestine (0.2). The cross-price elasticity between cigarettes and waterpipe tobacco was near zero, suggesting that the two products are not considered to be close substitutes by consumers.

CONCLUSIONS

These results serve as a strong evidence base for developing and implementing fiscal policies for tobacco control in the Eastern Mediterranean region that address cigarettes and waterpipe tobacco products.

Developing a Conversational agent (Chatbot) for Individuals Ambivalent about Quitting Smoking: A Study Protocol (Preprint)

BACKGROUND

Cigarette smoking is the leading preventable cause of disease and death in the United States. Despite the availability of a plethora of evidence-based smoking cessation resources, less than one-third of individuals who smoke seek cessation services, and individuals using these services are often those who are actively contemplating quitting smoking. There is a distinct dearth of low-cost, scalable interventions to support smokers not ready to quit (ambivalent smokers). Such interventions can assist in gradually promoting smoking behavior changes in this target population until motivation to quit arises, at which time they can be navigated to existing evidence-based smoking cessation interventions. Conversational agents or chatbots could provide cessation education and support to ambivalent smokers to build motivation and navigate them to evidence-based resources when ready to quit.

OBJECTIVE

The goal of our study is to test the proof-of-concept of the development and preliminary feasibility and acceptability of a smoking cessation support chatbot.

METHODS

We will accomplish our study aims in 2 phases. In phase 1, we will survey 300 ambivalent smokers to determine their preferences and priorities for a smoking cessation support chatbot. A "forced-choice experiment" will be administered to understand participants' preferred characteristics (attributes) of the proposed chatbot prototype. The data gathered will be used to program the prototype. In phase 2, we will invite 25 individuals who smoke to use the developed prototype. For this phase, participants will receive an overview of the chatbot and be encouraged to use the chatbot and engage and interact with the programmed attributes and components for a 2-week period.

RESULTS

At the end of phase 1, we anticipate identifying key attributes that ambivalent smokers prefer in a smoking cessation support chatbot. At the end of phase 2, chatbot acceptability and feasibility will be assessed. The study was funded in June 2022, and data collection for both phases of the study is currently ongoing. We expect study results to be published by December 2023.

CONCLUSIONS

Study results will yield a smoking behavior change chatbot prototype developed for ambivalent smokers that will be ready for efficacy testing in a larger study.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/44041.

Methods to Summarize Discrete-Choice Experiments in a Systematic Review: A Scoping Review

BACKGROUND AND OBJECTIVE

Systematic reviews of discrete-choice experiments (DCEs) are being increasingly conducted. The objective of this scoping review was to identify and describe the methodologies that have been used to summarize results across DCEs.

METHODS

We searched the electronic databases MEDLINE and EMBASE from inception to March 18, 2021, to identify English-language systematic reviews of patient preferences that included at least two DCEs and extracted data on attribute importance. The methods used to summarize results across DCEs were classified into narrative, semi-quantitative, and quantitative (meta-analytic) approaches and compared. Approaches to characterize the extent of preference heterogeneity were also described.

RESULTS

From 7362 unique records, we identified 54 eligible reviews from 2010 to Mar 2021, across a broad range of health conditions. Most (83%) used a narrative approach to summarize findings of DCEs, often citing differences in studies as the reason for not formally pooling findings. Semi-quantitative approaches included summarizing the frequency of the most important attributes, the frequency of attribute statistical significance, or tabulated comparisons of attribute importance for each pair of attributes. One review conducted a meta-analysis using the maximum acceptable risk. While reviews often commented on the heterogeneity of patient preferences, few (6%) addressed this systematically across studies.

CONCLUSION

While not commonly used, several semi-quantitative and one quantitative approach for synthesizing results of DCEs were identified, which may be useful for generating summary estimates across DCEs when appropriate. Further work is needed to assess the validity and usefulness of these approaches.

Brand-switching and tobacco taxation in Vietnam

BACKGROUND

The government of Vietnam is embarking on a radical tobacco excise tax reform, switching from the current pure ad valorem scheme to a mixed system by adding a specific component. There have been concerns raised by state-owned tobacco companies against this initiative that switching to a mixed scheme may shift consumption away from cheaper, domestic brands to more expensive, foreign brands (produced locally by joint ventures between multinational tobacco companies and domestic firms) and to illicit cigarettes, thus impairing the domestic industry, rather than reducing cigarette consumption effectively. Unfortunately, although this concern has been one of the biggest obstacles to the tobacco tax reform in the country, no study thus far has attempted to address it due mostly to the unavailability of relevant micro-market data with detailed information on brand choice.

OBJECTIVES

This research attempts to study cigarette brand substitution patterns and quantify the potential effect of the proposed tax structure change on cigarette brand choice to inform tax policy discussions in Vietnam.

METHODS

A discrete choice experiment is conducted to collect data on smokers' stated brand choice when cigarette prices change exogenously. Combined with data on their current cigarette consumption, random parameter logit models were estimated and then used to calculate brand-level price semielasticities as well as numerically simulate the impact of tax reforms on smoking.

RESULTS

Smokers are more likely to substitute a low-priced domestic brand with another domestic brand than either with a foreign brand or with an illicit brand, both of which are more expensive. Furthermore, the opt-out is one of the closest substitutes to low-priced brands and also the most sensitive to a change in their prices, implying that smokers of low-priced brands are more likely to buy none of the studied brands when cigarette prices increase. This provides strong suggestive evidence that they appear more likely to stop smoking when faced with higher cigarette prices. Imposing a specific tax tends to reduce the market share for both low-priced and high-priced licit brands, although the estimated market share reduction is larger for the former. In response to specific tax increases, a large share of current smokers do not intend to switch to illegal cigarette brands, but rather choose none of the experimented brands, suggesting their intention to quit. Finally, the magnitude of substitution to illicit brands tends to be negatively related to change in their prices as a result of the specific excise tax hike.

CONCLUSION

Contrary to the raised concern, smokers are more likely to substitute a domestic brand with another domestic brand than with a foreign brand. Moreover, the threat of illicit trade should not be exaggerated, and there are actions that the government of Vietnam can take to mitigate the threat effectively.

Standardised packs and larger health warnings: visual attention and perceptions among Colombian smokers and non-smokers

AIMS

To measure how cigarette packaging (standardised packaging and branded packaging) and health warning size affect visual attention and pack preferences among Colombian smokers and non-smokers.

DESIGN

To explore visual attention, we used an eye-tracking experiment where non-smokers, weekly smokers and daily smokers were shown cigarette packs varying in warning size (30%-pictorial on top of the text, 30%-pictorial and text side-by-side, 50%, 70%) and packaging (standardised packaging, branded packaging). We used a discrete choice experiment (DCE) to examine the impact of warning size, packaging and brand name on preferences to try, taste perceptions and perceptions of harm.

SETTING

Eye-tracking laboratory, Universidad Nacional de Colombia, Bogotá, Colombia.

PARTICIPANTS

Participants (n = 175) were 18 to 40 years old.

MEASUREMENTS

For the eye-tracking experiment, our primary outcome measure was the number of fixations toward the health warning compared with the branding. For the DCE, outcome measures were preferences to try, taste perceptions and harm perceptions.

FINDINGS

We observed greater visual attention to warning labels on standardised versus branded packages (F[3,167] = 22.87, P < 0.001) and when warnings were larger (F[9,161] = 147.17, P < 0.001); as warning size increased, the difference in visual attention to warnings between standardised and branded packaging decreased (F[9,161] = 4.44, P < 0.001). Non-smokers visually attended toward the warnings more than smokers, but as warning size increased these differences decreased (F[6,334] = 2.92, P = 0.009). For the DCE, conditional trials showed that increasing the warning size from 30% to 70% reduced preferences to try (odds ratio [OR] = 0.48, 95% CI = [0.42,0.54], P < 0.001), taste perceptions (OR = 0.61, 95% CI = [0.54,0.68], P < 0.001); and increased harm perceptions (OR = 0.78, 95% CI = [0.76,0.80], P < 0.001). Compared with branded packaging, standardised packaging reduced our DCE outcome measures with ORs ranging from OR = 0.25 (95% CI = [0.17,0.38], P < 0.001) to OR = 0.79 (95% CI = [0.67,0.93], P < 0.001) across two brands. These effects were more pronounced among non-smokers, males and younger participants. Unconditional trials showed similar results.

CONCLUSIONS

Standardised cigarette packaging and larger health warnings appear to decrease positive pack perceptions and have the potential to reduce the demand for cigarette products in Colombia.

Point-of-sale cigarette pricing strategies and young adult smokers' intention to purchase cigarettes: an online experiment

BACKGROUND

Point-of-sale tobacco marketing has been shown to be related to tobacco use behaviours; however, specific influences of cigarette price discounts, price tiers and pack/carton availability on cigarette purchasing intention are less understood by the tobacco control community.

METHODS

We conducted discrete choice experiments among an online sample of US young adult smokers (aged 18-30 years; n=1823). Participants were presented scenarios depicting their presence at a tobacco retail outlet with varying availability of cigarette price discounts, price tiers and pack/carton. At each scenario, participants were asked whether they would purchase cigarettes. Generalised linear regression models were used to examine the associations between of cigarette price discounts, price tiers and pack/carton with intention to purchase cigarettes overall and stratified by educational attainment.

RESULTS

Participants chose to purchase cigarettes in 70.9% of the scenarios. Offering price discounts were associated with higher odds of choosing to purchase cigarettes. Reducing the number of cigarette price tiers available in the store was associated with lower odds of choosing to purchase cigarettes. Stratified analysis showed that offering discounts on high-tier cigarette packs increased odds of choosing to purchase cigarettes among young adult smokers with at least some college education, while offering discounts on medium-tier cigarette packs increased odds of choosing to purchase cigarettes among those with some college education or less (eg, with a 10% discount, adjusted odds ratio [AOR]some college=1.62, 95% confidence interval [CI] 1.21 to 2.16; AOR≤high school=1.44, 95% CI 1.08 to 1.93).

CONCLUSIONS

Availability of cigarette price discounts, price tiers and pack/carton could potentially influence cigarette purchasing behaviours among young adult smokers. Regulating these marketing strategies may, therefore, reduce education-related smoking disparities.

Strategies to enhance the effects of pictorial warnings for cigarettes: results from a discrete choice experiment

AIMS

To measure the effects of changing attributes of pictorial health warning labels (HWLs) on cigarette packs in a country that has already implemented pictorial HWLs.

MEASURES

For each choice set, participants were presented with two cigarette packs and asked the following three questions: (1) 'If only these two cigarette packs were available, which would you buy?'; (2) 'Each of these two packs has warnings on the front and back about the health effects of smoking. Which of these warnings best informs you about the dangers from smoking?'; and (3) 'Which warning most makes you think about quitting smoking?'. As recommended for best practices in discrete choice experiments, each of these questions was followed by an 'opt-out' question for participants to indicate whether they really believed there was a difference between the options presented (i.e. 'Would you really choose one of them?'; 'Do you really think that either of these warnings informs you about dangers from smoking?'; or 'Do you really think that either of these warnings would make you think about quitting smoking?', respectively). Each choice set could be viewed for as long as the participant wished. For each choice question (i.e. willingness to buy, informative, motivating to quit), the pack chosen was coded as 1 and the other pack as 0, with both packs being given a value of 0 if the participant 'opted out'.

DESIGN

A within-subject discrete choice experiment that involved systematic manipulation of pictorial HWL size [75 versus 30% (current policy)]; inclusion of imagery on the back of the pack [versus none (current policy)]; and color formatting [black on yellow versus yellow on black (current policy)].

SETTING

Mexico, on-line panel.

PARTICIPANTS

Adult smokers (n = 705).

MEASUREMENTS

For each choice set, participants selected one pack as having the most informative HWL about smoking harms, the one that makes them think the most about quitting and the one they were most willing to buy. We assessed the independent and interactive effects of HWL attributes on choices.

FINDINGS

Larger HWL size on the pack front (75 versus 30%) and inclusion of a pictorial image on the pack back were both independently associated with lower willingness to buy a pack [b = -0.228, standard error (SE) = 0.023 and -0.089, SE = 0.016, respectively] and greater perception of an HWL as informative (b = 0.214, SE = 0.022, and 0.191, SE = 0.017, respectively) and motivating to quit (b = 0.251, SE = 0.023 and 0.194, SE = 0.017, respectively). HWL with black text and yellow background were perceived as less informative (b = -0.037, SE = 0.016) and less motivating to quit (b = -0.032, SE = 0.015) compared with yellow text on a black background.

CONCLUSIONS

Among adult Mexican smokers, pictorial health warning labels on cigarette packages that are larger or cover both sides of the pack appear more effective at lowering purchase intentions and increasing risk perceptions and motivation to quit than smaller health warning labels or health warning labels with imagery only on the pack front.

Utility maximization versus regret minimization in health choice behavior: Evidence from four datasets

Choice models in health are almost exclusively based on the neoclassical economic paradigm of utility maximization. Recently developed choice models have captured and shown empirical support for regret minimization as an alternative decision rule. In health economics, recent applications of RRM models indicate that individuals making health-based choices may exhibit regret minimization-type behavior. In this paper, we build on this research using a more flexible model that allows for heterogeneous decision rules, separately from preference heterogeneity, and comparing it to models that assume single decision rules. We use four datasets from diverse settings in which individuals make health choices: tobacco markets, genomic testing, and HIV prevention. We found that, if a one-size-fits-all rule is applied, then utility maximization was preferable to regret minimization for these datasets. However, we also find that individuals apply varying decision rules in similar proportions in these health settings, suggesting that models for heterogeneous decision rules were needed to capture these behaviors in these settings.

Perceived access to PrEP as a critical step in engagement: A qualitative analysis and discrete choice experiment among young men who have sex with men

Young Men who have Sex with Men (MSM) continue to face disproportionate HIV risk. Despite its well accepted role in HIV prevention, pre-exposure prophylaxis (PrEP) uptake remains below desired goals. Systemic barriers to PrEP access, including insurance complexity, cost, and wait times to start PrEP may contribute to low PrEP engagement. We conducted in-depth interviews and designed a discrete choice experiment (DCE) to assess preferences for and barriers to PrEP access in the United States. Methods: We conducted in-depth interviews with 18 MSM aged 18–30 years old who were not on PrEP and created a DCE based on the results. For the DCE, a convenience sample of young MSM in the United States who reported recent condomless anal sex was recruited through social media applications. Consenting participants provided sociodemographic information and responded to a series of 10 choice tasks about PrEP access. Preferences were analyzed utilizing marginal willingness-to-pay (mWTP) methods. Results: In-depth interviews revealed preferences for highly effective PrEP and concerns about barriers to access due to insurance coverage and privacy. The online DCE was completed by 236 eligible MSM aged 18–30. The most-preferred PrEP package—with all elements significantly preferred over other options—was insurance covered, could be maintained confidential from parents and employers, was available immediately, and had an online option. Need to take out new insurance or add a supplemental insurance in order to cover PrEP significantly detracted from willingness to pay for a PrEP program. Attributes most associated with willingness to pay for PrEP were PrEP being covered by an insurance the client already has and insurance coverage that was private. Conclusions: Young MSM at high risk for HIV in the United States who are not currently on PrEP showed strong preferences for PrEP options that were covered by insurance and could be kept confidential from parents and employers. Lack of these options may present major barriers to PrEP access among young MSM who are at particularly high risk. Rapid access to PrEP, as well as the option of receiving some care online, may also enhance PrEP uptake.

Impact of Little Cigars and Cigarillos Packaging Features on Product Preference

Background: We conducted a discrete choice experiment (DCE) among young adult cigarette smokers in the period July–August 2018 to examine their preference for cigarillos in response to various packaging-related attributes, including flavor, flavor description, quality descriptors, pack size, and prices. Methods: A convenience sample of 566 US young adult cigarette smokers aged 18–34, among whom 296 were current little cigar and cigarillo (LCC) smokers, were recruited using Facebook ads and invited to participate in an online (Qualtrics) tobacco survey containing DCE and tobacco use questions. In the experiment, participants chose among two cigarillo products or “neither” (opt-out). Results: We analyzed preferences for LCCs using multinomial, nested, random parameter logit models. Results showed that young adult cigarette smokers preferred grape over menthol, tobacco/regular, and wine flavors; “color only” and “color and text” flavor depictions over text only; “smooth” and “sweet” quality descriptors over “satisfying”; and larger pack sizes and lower prices. Conclusions: Regulating packaging-related features will impact LCC choices among US young adult smokers. FDA regulation over these packaging-related features may impact LCC use among young adult smokers.

Effects of pictorial warning label message framing and standardized packaging on cigarette packaging appeal among young adult smokers

INTRODUCTION

Pictorial warning labels and standardized "plain" packaging are policy interventions to reduce smoking, in part, by making cigarette packs and smoking less appealing. To inform potential policy decisions, this study examined the relative effects of message text framing (gain vs. loss) and cigarette packaging (standardized vs. branded) on appeal in a sample of young adult cigarette smokers.

METHODS

Cigarette smokers (N = 339) ages 18-30 completed two within-subjects experimental tasks. Tasks assessed the effects of message text framing (gain vs. loss) and packaging (standardized vs. branded) on cigarette packaging appeal. Task 1 was a 2 × 2 discrete choice experiment, where participants chose between each experimental pack and a standard branded cigarette pack without a pictorial warning label. Task 2 was a ranking task where participants ranked all packs on measures of appeal.

RESULTS

In Task 1, there were no significant differences in measures of appeal between packs displaying gain- vs. loss-framed message text, but all packs with pictorial warning labels significantly decreased appeal relative to standard branded packs without pictorial warning labels. Standardized packs with pictorial warning labels significantly reduced appeal relative to branded packs with pictorial warning labels and standard branded packs without pictorial warning labels. Task 2 pack rankings showed similar effects of pictorial warning labels and standardized packaging on appeal.

CONCLUSIONS

Pictorial warning labels with gain- and loss-framed text were equally powerful at reducing appeal of cigarette packs in young adult smokers relative to branded packs without pictorial warning labels, especially when combined with standardized packaging.

Kicking the habit is hard: A hybrid choice model investigation into the role of addiction in smoking behavior

Use of choice models is growing rapidly in tobacco research. These models are being used to answer key policy questions. However, certain aspects of smokers' choice behavior are not well understood. One such feature is addiction. Here, we address this issue by modeling data from a choice experiment on the US smokers. We model addiction using a latent variable. We use this latent variable to understand the relationship between choices and addiction, giving attention to nicotine levels. We find that more addicted smokers have stronger preferences for cigarettes and are unwilling to switch to e-cigarettes. Addicted smokers value nicotine in tobacco products to a much greater extent than those that are less addicted. Lastly, we forecast short-term responses to lowering nicotine levels in cigarettes. The results suggest that current nicotine-focused policies could be effective at encouraging addicted smokers to less harmful products and lead to substantial public health gains.

Physical Activity in the Daily Life of Adolescents: Factors Affecting Healthy Choices from a Discrete Choice Experiment

Physical activity improves peoples’ well-being and can help in preventing weight gain, obesity, and related non-communicable diseases. Promoting healthy behaviors in the daily travels and transport choices of adolescents is very important in early establishing healthy habits that imply routine physical activity. For designing and developing effective strategies, it is relevant to study adolescents’ preferences for physical activity and what factors in the social and environmental contexts affect their preferences. The paper investigates these aspects by means of a discrete choice experiment, using data from more than 4300 16–17 year-old adolescents in Italy. The results show that adolescents generally prefer walking for long time alone. However, females prefer cycling, while adolescents from lower educated families prefer motorized means of transport. Environmental factors affect the adolescents’ preferences: living nearby a green area is associated with more active and healthier choices in their short daily travels. Conversely, adolescents living closer to an industrial or high traffic area prefer to use motorized vehicles. Such findings have been discussed and policy implications presented, in order to support policymakers in designing cross-sectoral policies to promote healthy choices related to physical activity in adolescence.

Electronic cigarette and moist snuff product characteristics independently associated with youth tobacco product perceptions

INTRODUCTION

Tobacco product characteristics convey product attributes to potential users. This study aimed to assess independent contributions of specific e-cigarette and smokeless tobacco product characteristics to adolescents' perceptions about these products.

METHODS

In 2019-2020, students (N=1003) attending a convenience sample of 7 high schools in California (USA) were individually randomized to one of two discrete choice experiments, featuring either electronic cigarettes (e-cigarettes) or moist snuff. Participants were presented like-product pairs of randomlygenerated hypothetical tobacco products differing in device type, flavor, vapor cloud, and nicotine amount (for e-cigarettes) or differing in brand, flavor, cut, and price (for moist snuff). Within pairs, participants were asked about which product they were more curious, was more dangerous, would give a greater 'buzz,' and would be easier to use. Conditional logistic regression was used to quantify independent associations of product characteristics to participants' choices.

RESULTS

Each e-cigarette and moist snuff characteristic was independently associated with multiple product perceptions. All non-tobacco flavors were associated with more curiosity and perceived ease-of-use but lower perceived danger. Tank and pod-type e-cigarettes were viewed as easier to use and garnered more curiosity than 'cigalike' or 'drip-mod' devices. Smaller vapor cloud e-cigarettes and lower-price moist snuff were viewed as less dangerous, less buzz-inducing, and easier to use. Product ever users held stronger perceptions than never users about device type (e-cigarettes) and brands (moist snuff), while product naïve participants more strongly associated flavor with danger and buzz.

CONCLUSIONS

Tobacco product characteristics convey product attributes to adolescents that may increase appeal. Restricting specific characteristics, including flavors, could reduce positive perceptions of these products among youth.

Assessing cigarette packaging and labelling policy effects on early adolescents: results from a discrete choice experiment

INTRODUCTION

Cigarette packaging is a primary channel for tobacco advertising, particularly in countries where traditional channels are restricted. The current study evaluated the independent and interactive effects of cigarette packaging and health warning label (HWL) characteristics on perceived appeal of cigarette brands for early adolescents in Mexico.

METHODS

A discrete choice experiment (DCE) was conducted with early adolescents, aged 12-14 years (n=4251). The DCE involved a 3×25 design with six attributes: brand (Marlboro, Pall Mall, Camel), tobacco flavour (regular, menthol), flavour capsule (none, 1 or 2 capsules), presence of descriptive terms, branding (vs plain packaging), HWL size (30%, 75%) and HWL content (emphysema vs mouth cancer). Participants viewed eight sets of three cigarette packs and selected a pack in each set that: (1) is most/least attractive, (2) they are most/least interested in trying or (3) is most/least harmful, with a no difference option.

RESULTS

Participants perceived packs as less attractive, less interesting to try and more harmful if they had plain packaging or had larger HWLs, with the effect being most pronounced when plain packaging is combined with larger HWLs. For attractiveness, plain packaging had the biggest influence on choice (43%), followed by HWL size (19%). Interest in trying was most influenced by brand name (34%), followed by plain packaging (29%). Perceived harm was most influenced by brand name (30%), followed by HWL size (29%).

CONCLUSION

Increasing the size of HWLs and implementing plain packaging appear to reduce the appeal of cigarettes to early adolescents. Countries should adopt these policies to minimise the impact of tobacco marketing.

Agent-based Modeling in Tobacco Regulatory Science: Exploring 'What if' in Waterpipe Smoking

Objectives

Waterpipe tobacco smoking (WTS) is an emerging public health crisis, particularly among youth and young adults. Different from the use of other tobacco products and e-cigarettes, WTS tends to be a social activity occurring among friends or persons associated with social networks. In this paper, we review a potential strategy for WTS-related research.

Methods

As a bottom-up computational model, agent-based modeling (ABM) can simulate the actions and interactions of agents, as well as the dynamic interactions between agents and their environments, to gain an understanding of the functioning of a system. ABM is particularly useful for incorporating the influence of social networks in WTS, and capturing people's space-time activity and the spatial distribution of WTS venues.

Results

Comprehensive knowledge of WTS-related behaviors at the individual level is needed to take advantage of ABM and use it to examine policies such as the interaction between WTS and cigarette smoking and the effect of flavors used in waterpipe tobacco. Longitudinal and WTS-specific surveys and laboratory experiments are particularly helpful to understand WTS basic mechanisms and elicit individual preferences, respectively.

Conclusions

We argue that the uniqueness of WTS makes ABM a promising tool to be used in WTS-related research, as well as understanding use of other tobacco products.

E-cigarette Product Preferences among Adult Smokers: A Discrete Choice Experiment

OBJECTIVES

In this study, we used a discrete choice experiment (DCE) conducted August-October 2017 to examine electronic nicotine delivery systems (ENDS) product preferences in a national sample of adult smokers (N = 1154) who were also using ENDS or had not ruled out future use.

METHODS

The DCE evaluated 5 ENDS attributes: relative harm; effectiveness for helping smokers quit; nicotine strength; flavor; and price. We asked participants to choose among their own cigarettes, 2 ENDS products whose attributes varied across tasks, or none. We analyzed ENDS preferences using multinomial, nested, and mixed logit regressions.

RESULTS

Smokers preferred ENDS that are less harmful than cigarettes, are effective in helping smokers quit, are lower priced, and are not menthol-flavored. The marginal willingness to pay for an ENDS product was $8.40 when less harmful than cigarettes, $4.13 when of unknown effectiveness in helping quitting ($13.90 when effective), and $3.37 when ENDS are not menthol-flavored. Furthermore, the overall flavor preference is driven by tobacco smokers, not by menthol cigarette smokers who do prefer menthol-flavored ENDS.

CONCLUSIONS

Policies that affect perceptions of ENDS effectiveness in promoting cessation and their relative harm may alter smokers' ENDS preferences. Regulating flavors and price also may influence adult smokers' ENDS preference.

Sustainable Diet Dimensions. Comparing Consumer Preference for Nutrition, Environmental and Social Responsibility Food Labelling: A Systematic Review

Global food systems are currently challenged by unsustainable and unhealthy consumption and production practices. Food labelling provides information on key characteristics of food items, thereby potentially driving more sustainable food choices or demands. This review explores how consumers value three different elements of sustainable diets: Comparing consumer response to nutrition information on food labels against environmental and/or social responsibility information. Six databases were systematically searched for studies examining consumer choice/preference/evaluation of nutrition against environmental and/or social responsibility attributes on food labels. Studies were quality assessed against domain-based criteria and reported using PRISMA guidelines. Thirty articles with 19,040 participants met inclusion criteria. Study quality was mixed, with samples biased towards highly-educated females. Environmental and social responsibility attributes were preferred to nutrition attributes in 17 studies (11 environmental and six social), compared to nine where nutrition attributes were valued more highly. Three studies found a combination of attributes were valued more highly than either attribute in isolation. One study found no significant preference. The most preferred attribute was organic labelling, with a health inference likely. Consumers generally have a positive view of environmental and social responsibility food labelling schemes. Combination labelling has potential, with a mix of sustainable diet attributes appearing well-received.

The impacts of potency, warning messages, and price on preferences for Cannabis flower products

BACKGROUND

Recreational cannabis has been legalized in 11 states and Washington DC in the US. However, little is known about individual preferences for legal cannabis products. This study estimated the impacts of tetrahydrocannabinol (THC), cannabidiol (CBD), warning messages, and price on preferences for cannabis flowers.

METHODS

A cross-sectional online survey with discrete choice experiments was implemented in October 2017. A sample of 2400 adults aged 21 years or older were recruited from 6 US states with recreational cannabis legalization, consisting of 1200 past-year nonusers and 1200 past-year users. Each respondent was randomly assigned to 12 discrete choice scenarios, each asking them to choose from an opt-out option and 3 cannabis flower products with varying levels in THC, CBD, warning messages, and price. The impacts of product attributes on individual choices were analyzed with nested logit regressions.

RESULTS

Both cannabis nonusers and users preferred higher CBD and lower price. Users also preferred higher THC. The results on warning messages were mixed: graphic warning on drugged driving and text warning message had positive impacts on nonusers' and users' preferences for cannabis flowers, respectively, whereas FDA disapproval disclaimer had negative impacts on nonusers' preferences. Heterogeneities in preferences were revealed among nonusers by former use status and among users by reason of use. Particularly, medical cannabis users were not as responsive to THC as recreational cannabis users or dual users were. Regarding relative importance of the attributes, all respondents but medical cannabis users perceived price as the most important attribute (relative importance 51-64%), whereas medical cannabis users perceived CBD as the most important attribute (relative importance 47%).

CONCLUSION

The findings indicated that product characteristics may have influences on US adults' choices of legal cannabis flower products and may deserve consideration for cannabis regulatory framework.

The impact of flavors, health risks, secondhand smoke and prices on young adults' cigarette and e-cigarette choices: a discrete choice experiment

AIMS

To estimate young adults' preferences for cigarettes and e-cigarettes, and how preferences vary by policy-relevant factors. A related aim was to provide information on potential substitution/complementarity across cigarettes and e-cigarettes ahead of policy selection.

DESIGN

An online discrete choice experiment (DCE) in which respondents chose their preferred option among cigarettes, two types of e-cigarettes (disposable/reusable) and 'none'. Each cigarette-type was characterized by policy-relevant attributes: flavors, short-term health risks to self, secondhand smoke risks and price. A latent class model identified smoking types that respond differently to these.

SETTING

US tobacco market.

PARTICIPANTS

A total of 2003 young adults (aged 18-22 years) who ever tried either cigarettes or e-cigarettes, recruited via the survey platform Qualtrics, matched to the 2015 National Health Interview Survey by age, gender, education and census region.

MEASUREMENTS

Respondents' DCE choices.

FINDINGS

Young adults fell into two broad categories. One latent group, termed 'prefer smoking group', preferred cigarettes and another, 'prefer vaping group', preferred e-cigarettes. The 'prefer smoking group' preferred lower prices and lower health harms more than other attributes. The 'prefer vaping group' valued these, although price less intensely, and valued health and fruit/candy flavors more.

CONCLUSION

Banning all flavors in cigarettes and e-cigarettes might improve the health of young adults who ever tried either cigarettes or e-cigarettes. Young adult ever-triers might be deterred from smoking by increasing cigarette prices and encouraged to switch to e-cigarettes by reducing the health harms of e-cigarettes. Reducing health harms of e-cigarettes could also make the 'prefer vaping group' less likely to quit, resulting in increased health harm.

Discrete Choice Experiments in Health Economics: Past, Present and Future

OBJECTIVES

Discrete choice experiments (DCEs) are increasingly advocated as a way to quantify preferences for health. However, increasing support does not necessarily result in increasing quality. Although specific reviews have been conducted in certain contexts, there exists no recent description of the general state of the science of health-related DCEs. The aim of this paper was to update prior reviews (1990-2012), to identify all health-related DCEs and to provide a description of trends, current practice and future challenges.

METHODS

A systematic literature review was conducted to identify health-related empirical DCEs published between 2013 and 2017. The search strategy and data extraction replicated prior reviews to allow the reporting of trends, although additional extraction fields were incorporated.

RESULTS

Of the 7877 abstracts generated, 301 studies met the inclusion criteria and underwent data extraction. In general, the total number of DCEs per year continued to increase, with broader areas of application and increased geographic scope. Studies reported using more sophisticated designs (e.g. D-efficient) with associated software (e.g. Ngene). The trend towards using more sophisticated econometric models also continued. However, many studies presented sophisticated methods with insufficient detail. Qualitative research methods continued to be a popular approach for identifying attributes and levels.

CONCLUSIONS

The use of empirical DCEs in health economics continues to grow. However, inadequate reporting of methodological details inhibits quality assessment. This may reduce decision-makers' confidence in results and their ability to act on the findings. How and when to integrate health-related DCE outcomes into decision-making remains an important area for future research.

To "vape" or smoke? Experimental evidence on adult smokers

A growing share of the United States population uses e-cigarettes but the optimal regulation of these controversial products remains an open question. We conduct a discrete choice experiment to investigate how adult tobacco cigarette smokers' demand for e-cigarettes and tobacco cigarettes varies by four attributes: (i) whether e-cigarettes are considered healthier than tobacco cigarettes, (ii) the effectiveness of e-cigarettes as a cessation device, (iii) bans on use in public places, and (iv) price. We find that adult smokers' demand for e-cigarettes is motivated more by health concerns than by the desire to avoid smoking bans or higher prices.

Should flavours be banned in cigarettes and e-cigarettes? Evidence on adult smokers and recent quitters from a discrete choice experiment

OBJECTIVES

To provide the policy-relevant estimates of impacts of alternative flavour bans on preferences and demand for cigarettes and e-cigarettes in adult smokers and recent quitters.

METHODS

A best-best discrete choice experiment (DCE) is used to elicit smokers' and recent quitters' preferences for flavours, price, health impact and nicotine level in cigarettes and e-cigarettes. Choice of tobacco products and an opt-out option were examined. An efficient design yielded 36 choice sets. Exploded logit choice models were estimated. Flavour bans are modelled by restricting flavour coefficients in the estimated model.

SETTING AND PARTICIPANTS

A sample of 2031 adult smokers and recent quitters was recruited to complete an online survey and DCE.

RESULTS

Current smokers and recent quitters, on average, prefer cigarettes and menthol cigarettes over flavoured e-cigarettes. However, there is substantial preference heterogeneity by younger adults (ages 18-25), race/ethnicity and respondents with higher education. Our predictions suggest that a ban on menthol cigarettes would produce the greatest reduction in the choice of cigarettes (-5.2%), but with an accompanying increase in e-cigarettes use (3.8%). In contrast, banning flavours in e-cigarettes, while allowing menthol in cigarettes would result in the greatest increase in the selection of cigarettes (8.3%), and a decline in the use of e-cigarettes (-11.1%). A ban on all flavours, but tobacco in both products would increase 'opting-out' the most (5.2%) but would also increase choice of cigarettes (2.7%) and decrease choice of e-cigarettes (-7.9%).

CONCLUSIONS

A ban on flavoured e-cigarettes alone would likely increase the choice of cigarettes in smokers, arguably the more harmful way of obtaining nicotine, whereas a ban on menthol cigarettes alone would likely be more effective in reducing the choice of cigarettes. A ban on all flavours in both products would likely reduce the smoking/vaping rates, but the use of cigarettes would be higher than in the status quo. Policy-makers should use these results to guide the choice of flavour bans in light of their stance on the potential health impacts both products.