Menthol and filter ventilation in cigarettes: prevalence estimates and relationships with harm perception and smoking exposure.

INTRODUCTION: Menthol and filter ventilation (FV) contribute to cigarette appeal. This observational study examines the US prevalence of menthol versus non-menthol cigarette use by FV and how harm perceptions, cigarettes per day and biomarkers of exposure vary. METHODS: Population Assessment of Tobacco and Health Study (2013-2014) was merged with FV levels of cigarettes and restricted to daily smoking adults who had a usual cigarette variety and did not regularly use other tobacco (N=1614). Weighted descriptive statistics identified the prevalence of menthol and non-menthol use by low (0.02%-10.04%), moderate (10.05%-23.40%), high (23.41%-28.12%) and very high FV (28.13%-61.10%). Weighted linear regression was used to examine differences in outcomes by menthol/FV adjusted for potential confounders. RESULTS: The prevalence of a usual brand that was non-menthol, low FV was the lowest at 2.91%. Using non-menthol cigarettes with high and very high FV (≥23.4%) vs low FV (≤10.04%) was associated with a greater likeliness of misperceiving one's cigarette variety to be less harmful than other varieties (p values<0.05). Total nicotine equivalent, biomarker for nicotine exposure, was elevated (p values<0.05) among three non-menthol groups (low, moderate and very high FV) compared with two menthol groups (moderate, very high FV). CONCLUSION: The well-documented harm misperception linked to higher FV is more apparent in those using non-menthol than menthol cigarettes. Increased exposures were observed among some non-menthol cigarette users compared with some menthol cigarette users. These results should by no means delay a menthol ban but rather motivate concerted public health efforts to accompany the menthol ban to maximise smoking cessation.

Tobacco Constituents, Flavorants, and Paper Permeability of Factory-Made and Roll-Your-Own Cigarettes on the Australian Market.

INTRODUCTION: Roll-your-own (RYO) tobacco is a popular choice in Australia, with some people who smoke finding these products more attractive than factory-made cigarettes (FMC). Differences in visual and tactile properties and in the feel and taste of the smoke may contribute to this attractiveness. These differences may be driven by variation in tobacco constituents and wrapping paper permeability. However, to date, there has been no comparison of RYO and FMC products on the Australian market. AIMS AND METHODS: Chemical constituents, pH, flavorants, and paper permeability were compared in unburned RYO tobacco and tobacco from FMC. RYO and FMC products from matched brands were compared, as were products from the most popular FMC and RYO brands on the Australian market in 2018. RESULTS: RYO tobacco had higher moisture and humectant content (glycerol and propylene glycol) than FMC tobacco. RYO tobacco also had higher amounts of total and reducing sugars and lower nicotine when comparing the most popular brands. RYO papers were less permeable than FMC papers. Both RYO and FMC tobacco contained many chemicals identified as flavorants, including fourteen with known potential health risks. For most measured constituents and flavorants, RYO tobaccos had more in common with other RYO than FMC, with the commonalities remaining even when matched brands were compared. CONCLUSIONS: Higher levels of moisture, humectants, and sugars in Australian RYO tobacco compared to FMC may be increasing attractiveness of RYO by reducing the harsh taste of the smoke and increasing the moist feel of the tobacco. IMPLICATIONS: While price is the main factor driving the use of RYO tobacco, some people who smoke find these products more attractive. This study has shown that Australian RYO tobacco contains higher amounts of glycerol, propylene glycol, and sugars than FMC. These chemicals may be improving the taste of the tobacco, as well as creating a moist feel that is falsely perceived as indicating that the tobacco is "fresh" and "less chemically." Ironically, it may be that higher amounts of some added chemicals in RYO contribute to false perceptions of a more natural and less harmful product.

American Indian Perspectives on Culturally Aligning a Digital Smoking Cessation Resource.

INTRODUCTION: Innovative smoking cessation approaches that overcome barriers such as traveling to program site or that require the staff and infrastructure for sustaining are likely needed to improve smoking quit rates among American Indian (AI) peoples in the United States. In this study, qualitative methods identified recommendations from AI peoples to guide alignment of an evidence-based smoking cessation smartphone app (i.e., QuitGuide) to the culture and needs of AI persons. METHODS: Semi-structured interviews were conducted with AI adults who smoke (n = 40) and with public health professionals (n = 6). Questions included: "The app asks if something triggered you to slip and lists several options. What options were you expecting to see on this list?" as well as how to make the app more engaging such as "What would make the app more helpful for AI peoples, like you, who want to quit smoking?." Constant comparative techniques were used to develop codes and themes. RESULTS: Loss, grief, and not accessing traditional tobacco were put forward as smoking triggers to be addressed in the app. Features that help users connect with and learn about AI cultures and promote healing, such as encouraging traditional tobacco use, being in community, embracing Native spirituality, and participating in cultural crafting were recommended. Some noted the need to motivate AI peoples to think about legacy and ability to care for younger generations and Indigenizing the app with Native imagery. CONCLUSIONS: Themes pointed towards promotion of strengths-based factors, such as healing, cultural connectedness and traditional tobacco use, in the app. IMPLICATIONS: Results will be used to culturally align a smartphone app for smoking cessation among AI peoples and may be insightful for other tribal, federal, and state public health efforts aimed at advancing health equity for AI peoples.

Society for Research on Nicotine and Tobacco as an Outgrowth of the 1988 Surgeon General's Report on Nicotine Addiction: Reflections of the Early Presidents.

INTRODUCTION: The Society for Research on Nicotine and Tobacco began in the United States as a scientific organization "to stimulate the generation and dissemination of new knowledge concerning nicotine and tobacco in all its manifestations." Now in its 30th year, the Society is taking on new challenges in tobacco control, nicotine vaping, product regulation, and public policy. AIMS AND METHODS: This Review describes the formative years of the Society from the perspective of researchers who were in leadership positions during that time, documenting how biobehavioral and clinical research in the first 10 years was a continuation of the scientific mission of the 1988 United States Surgeon General's Report on Nicotine Addiction and summarizing organizational innovations during each president's term of office. CONCLUSIONS: The Society's promotion of scientific research served as a catalyst for funding, policy, and regulation, setting the stage for its influence and credibility. IMPLICATIONS: This Commentary provides context and an overview of the scientific research and the organizational innovations that occurred during the early years of the Society for Research on Nicotine and Tobacco using publications and available documentation. The Society was able to thrive because biobehavioral research on nicotine addiction provided the scientific underpinnings for the tobacco control enterprise as a whole. The objective of this Commentary is to describe formative events in the Society's history based on the accomplishments of its early leaders.

Biobehavioral and affective stress responses during nicotine withdrawal: Influence of regular cannabis co-use.

BACKGROUND: Co-use of cannabis is increasing in nicotine users and presents additional challenges in addressing nicotine dependence. This study examined the links between regular co-use of cannabis and nicotine with biobehavioral and affective changes in response to stress during nicotine withdrawal and ad libitum use. METHODS: Participants (N = 79) who regularly used nicotine-only, cannabis-only, both substances, or neither substance were invited to attend two laboratory stress assessment sessions. For nicotine users, one session occurred during ad libitum nicotine use and one occurred after abstinence from nicotine. During the stress sessions, participants provided saliva samples for cortisol assay and completed measures of subjective states. Cardiovascular measures were collected during resting baseline, exposure to acute stressors, and a recovery rest period. RESULTS: Nicotine-only users had higher average cortisol levels in the second lab session (nicotine withdrawal) relative to the first lab session (ad libitum nicotine use). Compared to nicotine non-users, nicotine users reported less positive affect and exhibited attenuated cortisol and systolic blood pressure (BP) stress responses. Cannabis users exhibited exaggerated diastolic BP responses to stress compared to cannabis non-users, and co-users of nicotine and cannabis had higher levels of cannabis craving than cannabis-only users (p < .01). CONCLUSIONS: This study partially replicated earlier findings on the effects of chronic nicotine use and provided novel results regarding the influence of cannabis co-use on physiological and affective responses to stress in nicotine users during nicotine withdrawal.

Relationship Between Tobacco Product Use and Health-Related Quality of Life Among Individuals With COPD in Waves 1-5 (2013-2019) of the Population Assessment of Tobacco and Health Study.

Introduction: We examined the association between tobacco product use and health-related quality of life (HRQoL) among individuals with chronic obstructive pulmonary disease (COPD) in Waves 1-5 of the Population Assessment of Tobacco and Health (PATH) Study. Methods: Adults ≥40 years with an ever COPD diagnosis were included in cross-sectional (Wave 5) and longitudinal (Waves 1 to 5) analyses. Tobacco use included 13 mutually exclusive categories of past 30-day (P30D) single use and polyuse with P30D exclusive cigarette use and ≥5-year cigarette cessation as reference groups. Multivariable linear regression and generalized estimating equations (GEE) were used to examine the association between tobacco use and HRQoL as measured by the Patient-Reported Outcomes Measurement Information System (PROMIS) Global-10 questionnaire. Results: Of 1670 adults, 79.4% ever used cigarettes; mean (standard error [SE]) pack years was 30.9 (1.1). In cross-sectional analysis, P30D exclusive cigarette use, and e-cigarette/cigarette dual use were associated with worse HRQoL compared to ≥5-year cigarette cessation. Compared to P30D exclusive cigarette use, never tobacco use and ≥5-year cigarette cessation were associated with better HRQoL, while e-cigarette/cigarette dual use had worse HRQoL. Longitudinally (n=686), e-cigarette/cigarette dual use was associated with worsening HRQoL compared to both reference groups. Only never tobacco use was associated with higher HRQoL over time compared to P30D exclusive cigarette use. Conclusions: E-cigarette/cigarette dual use was associated with worse HRQoL compared to ≥5-year cigarette cessation and exclusive cigarette use. Never use and ≥5-year cigarette cessation were the only categories associated with higher HRQoL compared to exclusive cigarette use. Findings highlight the importance of complete smoking cessation for individuals with COPD.

Heterogeneity of Harmful Constituent Profiles in Smokeless Tobacco Products from Five African Countries.

Addictive, toxic, and carcinogenic constituents present in smokeless tobacco (SLT) products are responsible for the harmful effects associated with SLT use. There are limited data on levels of such constituents in SLT products used in Africa, a region with high prevalence of SLT use and the associated morbidity and mortality. Manufactured and custom-made SLT products were purchased from five African countries (South Africa, Uganda, Mauritania, Nigeria, and Zambia) using a standard approach for sample collection, labeling, and storage. Moisture content, pH, total and unprotonated (biologically available) nicotine, five tobacco-specific N-nitrosamines (TSNA), 10 polycyclic aromatic hydrocarbons (PAH), five metals and metalloids (As, Cd, Cr, Ni, and Pb), nitrate, and nitrite were analyzed. A total of 54 samples representing 15 varieties of manufactured SLT products and 13 varieties of custom-made SLT products were purchased and analyzed. In all samples, the total nicotine ranged from 1.6 to 20.5 mg/g product and unprotonated nicotine accounted for 5.3-99.6% of the total nicotine content. The sum of all five TSNA ranged from 1.6 to 100 µg/g product, with significant within-country variations observed across both the manufactured and custom-made varieties. Significant variations were also found for PAH, metals and metalloids, nitrates, and nitrites. This is the most comprehensive report on the chemical profiling of products from African countries. This is also the first study illustrating the variability of harmful constituents within the same types and brands of African SLT. Our findings emphasize the need for consumer education and interventions to reduce SLT use in Africa. The data reported here can be useful to regulators in considering measures to prevent the occurrence of high levels of known toxicants and carcinogens in manufactured products.

Illegal product purchasing in the experimental tobacco marketplace: Effects of menthol cigarette and cigarette ventilation ban.

BACKGROUND: Tobacco regulations may increase demand for illegal cigarettes. We use the Experimental Tobacco Marketplace to estimate the impact of banning menthol cigarettes (Experiment 1) and decreasing allowable cigarette filter ventilation levels (Experiment 2). METHODS: Crowdsourced participants were randomized into one of four groups (2×2 factorial design). Experiment 1 included menthol availability (yes/no) by purchasing option (legal only vs illegal available). Experiment 2 included filter-vented cigarettes availability (yes/no) by purchasing option (legal only vs illegal available). Participants were given an individualized budget to purchase tobacco. Percent budget spent was the outcome measure. RESULTS: Experiment 1, with a legal marketplace only, non-menthol cigarette purchasing was lower (p=0.010) and electronic-cigarette purchasing was higher (p=0.016), when cigarettes were banned compared to when they were available. With an illegal marketplace, switching to legal non-menthol cigarettes was less likely (p<0.001) and purchasing illegal menthol cigarettes was higher (p<0.001), when cigarettes were banned compared to when they were available. Experiment 2, with a legal marketplace only, cigarette purchasing was lower (p=0.010), when the participant's filtered vented cigarettes were banned compared to when they were available. With an illegal marketplace, purchasing the legal low-ventilated cigarette option was lower (p<0.001) and significant differences in illegal filter-vented cigarette purchasing were not observed, when their filter-vented cigarettes were banned compared to when they were available legally. CONCLUSIONS: Without an illegal option, both restrictions decreased cigarette purchasing, but the menthol ban increased e-cigarette purchasing. With an illegal option, a menthol ban increased illegal cigarette purchasing, but decreasing filter ventilation did not.

Perceived Truthfulness of Reduced Lung Cancer Risk Advertising Claims Influences Consumers' Intention to try and to Purchase Snus.

The objective of the current study was to evaluate the impact of a reduced risk claim about lung cancer, presented in various formats, on smokers' and non-smokers' interest in trying Camel Snus and intention to purchase Camel Snus. We varied claim formats by varying advertising messages for Camel Snus in 4 ways (1) text only; (2) bar chart; (3) text/testimonial; and (4) bar chart/testimonial. 3001 participants were recruited from a web-based consumer specialty panel via an email invitation. In 2015, a second study was conducted, using similar methods, where 3001 additional participants were recruited. Overall, controlling for other factors, the presence of an MRTP claim was not significantly related to interest in trying snus [X2 (4) = 8.567, P = .073], or purchase intentions [X2 (4) = 1.148, P = .887]. Relative to a control ad where no explicit health risk claim was made, the Graphic + testimonial [OR = 1.29] or Text only [OR = 1.41] claims did significantly increase interest in trying Camel Snus. However, the adverting format did not impact interest in purchasing Camel Snus. While current smokeless tobacco users (95%) and smokers (59%) expressed interest in trying Camel Snus, non-tobacco users (7%) showed low interest in trying or purchasing Camel Snus (P < .001). Interest in trying Camel Snus was stronger in younger smokers compared to older smokers. Among current smokers, worry about lung cancer (the key focus of the reduced risk claim) was not associated with interest in trying Camel Snus or with purchase intention [OR = .91, 95% CI: .72, 1.14] or intention to purchase snus [OR = 1.07, 95% CI: .86, 1.32]. Future research should evaluate how claim and messaging formats influence perceived truthfulness and whether this effect differs among sub-groups of consumers, such as adolescents, those with tobacco-related disease, and former smokers. It will also be helpful to understand whether perceptions of ad truthfulness result in changes in product use patterns over time. In sum, giving people truthful, credible information about relative product risks, such as through authorized MRTP claims, is important, but such information is likely insufficient to get smokers to switch.

Testing the influence of harm reduction messages on health risk attitudes, injunctive norms and perceived behavioral control.

BACKGROUND: E-cigarettes can potentially be a harm reduction pathway for adults who smoke and who are seeking to make the complete switch from cigarettes. However, often people who smoke believe that e-cigarettes are just as damaging as cigarettes to their health. From a harm reduction perspective, the key question is whether providing information about the reduced toxicant intake of e-cigarettes, compared to cigarettes, could influence their perceptions and whether there are certain message features that might further support this transition. METHODS: In this experiment (n = 305), we test whether a harm reduction (reduced toxicant intake, complete switch) message will influence the health risk attitudes, injunctive norms and perceived behavioral control of people who smoke, compared to those who do not view a message and whether including a "smoking cue" within the message influences their response. RESULTS: Results indicate that those who viewed the harm reduction message with a smoking cue had lower health risk attitudes than those who did not view a message (p = 0.025) and higher injunctive norms than those who viewed the message without a smoking cue (p = 0.006). CONCLUSIONS: These findings demonstrate that a harm reduction message with a smoking cue can influence the perceptions of adults who smoke, lowering health risk attitudes and increasing injunctive norms.

Illusion of filtration: Evidence from tobacco industry documents.

INTRODUCTION: We compared the design features of popular filtered and non-filtered cigarettes sold in the United States between 1960 and 1990, to assess the relationship between cigarette filter and tobacco weight. METHODS: We analyzed data on the design features of six popular filtered and three non-filtered cigarette brands sold in the US including the weight of tobacco used provided in the Cigarette Information Reports produced by Philip Morris Tobacco Company between 1960 and 1990. We also collected information on other design features such as stick length and circumference, the percentage of reconstituted tobacco in the blend, among other product parameters. We used joinpoint regression to test for trends in outcome variables for each brand assessed between 1960 and 1990. RESULTS: In all years, filtered cigarettes had less tobacco by weight compared to non-filtered cigarettes. The lower average weight of tobacco found in filtered cigarettes appears to be due to a combination of factors including stick and filter length, and the amount of reconstituted tobacco in the blend. The average percentages of total alkaloids and expanded tobacco increased over time but were similar between filtered and non-filtered brands. CONCLUSIONS: While various design features of popular filtered and non-filtered brands changed between 1960 and 1990, the observed reduction in tobacco weight among filtered brands was perhaps the most salient in terms of disease risk. Less tobacco in a filtered cigarette calls into question the presumed exclusive role of cigarette filter tips in the reduced health risks of filtered versus non-filtered cigarette smoking.

Tobacco Free Nicotine Vaping Products: A Study of Health Halo Effects Among Middle School Youth.

Health halo effects are a form of biased processing, wherein a particular product claim bleeds over to other categories of analysis or to an overall healthier impression. This study tests whether the term tobacco-free nicotine triggers a health halo effect. Through an experiment with middle school youth (n = 599), we vary the flavor (tobacco vs. fruit) and nicotine source information (nicotine/tobacco-free nicotine/nicotine from tobacco) on the warning label of the vaping product participants viewed. We evaluate product measures (nicotine content beliefs, nicotine source beliefs, and risk perceptions) and comparative nicotine source misperceptions (addictiveness, safety, and risk). Findings show that the term tobacco-free nicotine triggers inaccurate nicotine content beliefs, nicotine source beliefs, and misperceptions associated with addictiveness, safety, and risk. We conclude with theoretical and regulatory implications.

Validating Wave 1 (2014) Urinary Cotinine and TNE-2 Cut-points for Differentiating Wave 4 (2017) Cigarette Use from Non-use in the United States Using Data from the PATH Study.

BACKGROUND: Sex and racial/ethnic identity-specific cut-points for validating tobacco use using Wave 1 (W1) of the Population Assessment of Tobacco and Health (PATH) Study were published in 2020. The current study establishes predictive validity of the W1 (2014) urinary cotinine and total nicotine equivalents-2 (TNE-2) cut-points on estimating Wave 4 (W4; 2017) tobacco use. METHODS: For exclusive and polytobacco cigarette use, weighted prevalence estimates based on W4 self-report alone and with exceeding the W1 cut-point were calculated to identify the percentage missed without biochemical verification. Sensitivity and specificity of W1 cut-points on W4 self-reported tobacco use status were examined. ROC curves were used to determine the optimal W4 cut-points to distinguish past 30-day users from non-users, and evaluate whether the cut-points significantly differed from W1. RESULTS: Agreement between W4 self-reported use and exceeding the W1 cut-points was high overall and when stratified by demographic subgroups (0.7%-4.4% of use was missed if relying on self-report alone). The predictive validity of using the W1 cut-points to classify exclusive cigarette and polytobacco cigarette use at W4 was high (>90% sensitivity and specificity, except among polytobacco Hispanic smokers). Cut-points derived using W4 data did not significantly differ from the W1-derived cut-points [e.g., W1 exclusive = 40.5 ng/mL cotinine (95% confidence interval, CI: 26.1-62.8), W4 exclusive = 29.9 ng/mL cotinine (95% CI: 13.5-66.4)], among most demographic subgroups. CONCLUSIONS: The W1 cut-points remain valid for biochemical verification of self-reported tobacco use in W4. IMPACT: Findings from can be used in clinical and epidemiologic studies to reduce misclassification of cigarette smoking status.

Indicators of Tobacco Dependence Among Youth: Findings From Wave 1 (2013-2014) of the Population Assessment of Tobacco and Health Study.

BACKGROUND: Prior work established a measure of tobacco dependence (TD) among adults that can be used to compare TD across different tobacco products. We extend this approach to develop a common, cross-product metric for TD among youth. METHODS: One thousand one hundred and forty-eight youth aged 12-17 who used a tobacco product in the past 30 days were identified from 13 651 youth respondents in Wave 1 of the Population Assessment of Tobacco and Health (PATH) Study. FINDINGS: Analyses confirmed a single primary latent construct underlying responses to TD indicators for all mutually exclusive tobacco product user groups. Differential Item Functioning analyses supported the use of 8 of 10 TD indicators for comparisons across groups. With TD levels anchored at 0.0 (standard deviation [SD] = 1.0) among cigarette only (n = 265) use group, mean TD scores were more than a full SD lower for e-cigarette only (n = 150) use group (mean = -1.09; SD = 0.64). Other single product use group (cigar, hookah, pipe, or smokeless; n = 262) on average had lower TD (mean = -0.60; SD = 0.84), and the group with the use of multiple tobacco products (n = 471) experienced similar levels of TD (mean = 0.14; SD = 0.78) as the cigarette only use group. Concurrent validity was established with product use frequency among all user groups. A subset of five TD items comprised a common metric permitting comparisons between youth and adults. CONCLUSION: The PATH Study Youth Wave 1 Interview provided psychometrically valid measures of TD that enable future regulatory investigations of TD across tobacco products and comparisons between youth and adult tobacco product use group. IMPLICATIONS: A measure of tobacco dependence (TD) has been established previously among adults to compare TD across tobacco products. This study established the validity of a similar, cross-product measure of TD among youth. Findings suggest a single latent TD construct underlying this measure, concurrent validity of the scale with product use frequency across different types of tobacco users, and a subset of common items that can be used to compare TD between youth and adults who use tobacco.

Associations between biomarkers of nicotine/tobacco exposure and respiratory symptoms among adults who exclusively smoke cigarettes in the U.S.: Findings from the PATH Study Waves 1-4 (2013-2017).

Significance: Determining if tobacco-related biomarkers of exposure (BOE) are associated with respiratory symptoms is an important public health tool that can be used to evaluate the potential harm of different tobacco products. Methods: Adult data from people who exclusively smoked cigarettes (N = 2,438) in Waves 1-4 (2013-2017) of the Population Assessment of Tobacco and Health Study were stacked to examine associations between baseline and follow-up within wave pairs (W1-W2, W2-W3, W3-W4). Weighted generalized estimating equation models were used to evaluate associations between biomarkers of nicotine, tobacco-specific nitrosamines, acrolein, acrylonitrile, cadmium, and lead at baseline/follow-up and respiratory symptom(s) (wheezing/whistling in the chest, wheezing during exercise, and/or dry cough in the past 12 months) at follow-up. Results: Higher acrolein metabolite (CEMA) levels at follow-up were associated with increased odds of respiratory symptoms at follow-up for people who exclusively smoked cigarettes (aOR = 1.34; 95% CI = 1.06, 1.70), including when limited to those without a diagnosed respiratory disease (aOR = 1.46; 95% CI = 1.12, 1.90) and those who smoked daily (aOR = 1.40; 95% CI = 1.06, 1.84). Higher cadmium levels at baseline (while controlling for follow-up levels) were associated with reduced odds of respiratory symptoms at follow-up (aOR = 0.80; 95% CI = 0.65, 0.98) among people who exclusively smoked cigarettes without a respiratory disease. There were no significant associations between baseline/follow-up BOE and follow-up respiratory symptoms for people who smoked cigarettes non-daily. Conclusions: This research supports measuring biomarkers of acrolein, such as CEMA, as a potential intermediate measurement for increased respiratory symptom development. Measuring these biomarkers could help alleviate the clinical burden of respiratory disease.

Qualitative reactions to a low nicotine product standard for cigarettes from adolescents and young adults living in the United States who smoke.

The Biden Administration is considering a low nicotine product standard for cigarettes. This qualitative study examined reactions to a nicotine reduction policy among adolescents and young adults (AYA) who smoke cigarettes. After completing a lab study involving masked exposure either to low nicotine or normal nicotine research cigarettes and unmasked exposure to e-cigarettes varying in nicotine concentration and flavor, we conducted follow-up semi-structured interviews (N = 25) to explore participants' knowledge, attitudes, and perceptions of a low nicotine product standard and their anticipated tobacco use behavior after policy implementation. Interviews were audio-recorded, transcribed verbatim, double-coded, and analyzed using reflexive thematic analysis. Nearly half of participants supported the policy because they thought it would prevent young people from starting smoking and/or would help people quit. Reasons some participants opposed the policy included beliefs that adults should have the choice to smoke or that a nicotine reduction policy is counterintuitive because the government benefits from cigarette sales. Others believed the policy would be ineffective because youth could circumvent the policy (e.g., illicit market) or would increase their smoking to maintain the same nicotine level. Almost half of participants said they would quit smoking while the other half said they would continue smoking, although potentially reduce their smoking. Overall, our qualitative findings point to the need for pre-policy media campaigns targeting AYA who smoke to minimize negative reactions, dispel fears, and correct misperceptions as well as encourage quitting and provide information on accessing cessation resources.

Practical guidance on modeling choices for the virtual twins method.

Individuals can vary drastically in their response to the same treatment, and this heterogeneity has driven the push for more personalized medicine. Accurate and interpretable methods to identify subgroups that respond to the treatment differently from the population average are necessary to achieving this goal. The Virtual Twins (VT) method is a highly cited and implemented method for subgroup identification because of its intuitive framework. However, since its initial publication, many researchers still rely heavily on the authors' initial modeling suggestions without examining newer and more powerful alternatives. This leaves much of the potential of the method untapped. We comprehensively evaluate the performance of VT with different combinations of methods in each of its component steps, under a collection of linear and nonlinear problem settings. Our simulations show that the method choice for Step 1 of VT, in which dense models with high predictive performance are fit for the potential outcomes, is highly influential in the overall accuracy of the method, and Superlearner is a promising choice. We illustrate our findings by using VT to identify subgroups with heterogeneous treatment effects in a randomized, double-blind trial of very low nicotine content cigarettes.

The impact of the COVID-19 pandemic on a sample of US young adults who smoke cigarettes: A qualitative analysis.

INTRODUCTION: The ongoing COVID-19 pandemic has been associated with increased negative mood in youth, and a few reports of changes in tobacco use. We sought to increase the depth of knowledge on the effects of the pandemic on early young adult mood states, access to tobacco products and tobacco use behaviors, and knowledge of risks associated with tobacco use and COVID-19 by learning more about the lived experience of the pandemic among young adults early in their smoking trajectories. METHODS: Semi-structured qualitative interviews were conducted with 25 young adults ages 18-20 (M = 19) who smoked cigarettes daily or nearly every day and had used electronic cigarettes (ECs) on ≥ 2 occasions in their lifetime. RESULTS: Our results uncovered several themes: 1) The majority of teens experienced mental health disturbances as a result of the pandemic, which manifested as depression, anxiety, and/or acute loneliness due to social isolation; 2) tobacco purchasing behaviors sometimes changed, with both greater and less access reported among participants; 3) changes in tobacco use were also reported, with some reporting increases in use, others reporting decreases, and a few reporting quitting; and 4) while some youth reported that tobacco use could increase their risk related to COVID-19, the majority reported confusion and uncertainty about how tobacco use impacted their risk. CONCLUSIONS: The themes identified specific factors that may account for the heterogeneity of impacts of the pandemic on tobacco use, and highlight the value of qualitative work for centering the lived experience of youth for understanding larger trends in substance use.