Abstract
Aims
To identify, visualize, and describe the prevalence of within-product patterns of tobacco use behaviors for e-cigarettes, cigarettes, and hookah (TP) by 3 age groups (ie, 12-14-year-old, 15-17-year-old, and 18-20-year-old) with U.S. nationally representative data.
Methods
In 2014-2015, never users of each (TP) and age group were followed-up longitudinally between 2015-2019 using five transition states: non-susceptible to (TP) use, susceptible to (TP) use, ever (TP) use, past 30-day (TP) use, and discontinued past 30-day (TP) use. Sankey diagrams were used to graphically visualize patterns in tobacco use behaviors across time.
Results
Among 12-14-year-old who were never users and susceptible to each TP from 2014-2017, 7% initiated ever e-cigarette use and 9.4% first reported past 30-day use by 2018-2019; 5.8% initiated ever cigarette use and 3% first reported past 30-day cigarette use by 2018-2019; and, 4.5% initiated ever hookah use and 1.0% first reported past 30-day hookah use by 2018-2019. Among 15-17-year-old who were never users and susceptible to each TP from 2014-2017, 4.2% initiated ever e-cigarette use and 9.0% first reported past 30-day use by 2018-2019; 4.5% initiated ever cigarette use and 3% first reported past 30-day cigarette use by 2018-2019; and, 4.5% initiated ever hookah use and 2.4% first reported past 30-day hookah use by 2018-2019. Among 18-20-year-old who were never users and susceptible to each TP from 2014-2017, 3.2% initiated ever e-cigarette use and 3.6% first reported past 30-day e-cigarette use by 2018-2019; 3.0% initiated ever cigarette use and 2.3% first reported past 30-day cigarette use; and, 2.8% initiated ever hookah use and 1.0% first reported past 30-day hookah use by 2018-2019.
Conclusions
From 2014 to 2019, onset and progression of e-cigarette, cigarette, and hookah use occurred more frequently in 12-14 and 15-17-year-old than in young adults 18-20-year-old.
Keywords
Introduction
Tobacco use remains high among youth and young adults despite recent efforts to curb tobacco initiation in the context of the evolving tobacco product landscape1-7. A recent report of the 2021 National Youth Tobacco Survey (NYTS) indicated that 19.4%, 8.1% and 2.8% of middle and high school students, had ever used e-cigarettes, cigarettes, and hookah, respectively 1 . In this study, 6.6 million middle and high school students reported using any tobacco product (TP) in 2021. The 2019 National Health Interview Survey found that regular e-cigarette use (every day or some days) was higher among young adults (18-24 years old) at 24.5% compared to older adults, and was around 20% and 10% for hookah and cigarettes, respectively 8 .
Understanding longitudinal patterns of tobacco use behaviors is central to curbing tobacco initiation, as this information can identify windows of opportunity in which to intervene to prevent or reduce progression in the severity or intensity of tobacco use2-7. This is particularly important among never users of a particular TP who may be susceptible to initiation of a particular TP and later on progress to regular TP use. Susceptibility is defined as the absence of a firm commitment not to start using TPs in the future and its use has been validated for e-cigarettes,9,10 cigarettes, 11 and hookah. 9 A 2013-2014 PATH study found that among youth (12-17) never users, 27.4%, 28.6% and 22.0% reported susceptibility to e-cigarette, cigarette, and hookah use, respectively. 12 Previous research has found that middle and high school students who reported susceptibility to e-cigarettes had increased initiation of ever use and past 30-day use after 6 months of follow-up 13 . A college student study in North Carolina and Virginia found that those who were susceptible to hookah had 2.5 (95%CI = 1.39- 4.60) times the risk of initiating hookah use, 1 year later 14 . Initiation or onset of TP use is typically measured by ever (ie, lifetime) use of a product, while progression in tobacco use is measured by past 30-day use. 15
While many studies have examined the transition from susceptibility to ever use across 1 or 2 years of follow-up for e-cigarettes, cigarettes, and hookah,9,13,14,16,17 as well as research on transitions and trajectories of multiple TP use,18-26 there is a paucity of research on exploring transition patterns among never users who are susceptible and never users who are non-susceptible, to ever use and progression of TP use, especially with extended follow-up time. This study sought to fill this gap, namely, to identify, visualize, and describe within-product tobacco use longitudinal transition patterns for: e-cigarettes, cigarettes, and hookah by 3 age groups: 12-14-year-olds, 15-17-year-olds, and 18-20-year-olds among never users of each TP in 2014-2015 and follow-up until 2018-2019 using the Population Assessment of Tobacco and Health (PATH) study in the U.S.A. Our analyses describe these longitudinal transition patterns of from never users of each TP who are susceptible and those who are not susceptible to each TP in 2014-2015 by each age group. E-cigarettes, cigarettes, and hookah were chosen, as they have the highest prevalence of use in the U.S.A. among youth and young adults. The natural history of the onset and progression of tobacco use among young people, in the absence of intervention is important as the results presented will allow investigators to identify at which age to conduct interventions for young people from a population perspective.
Methods
Study Design
The PATH study is an ongoing nationally representative study of tobacco use behaviors in U.S.A. youth and adults, and its methodology has been described previously. 27 Secondary analyses of waves 2-5 (2014-2019) youth and adult restricted-use datasets were implemented. Wave 2 data was collected from October 2014-October 2015, wave 3 from October 2015-October 2016, wave 4 from December 2016-January 2018, and wave 5 from December 2018-November 2019. Wave 1 data was collected in 2013-2014 but is not included because susceptibility questions were not asked among young adults until wave 2. Wave 4.5 (December 2017- September 2020) was only collected among youth and for this reason we did not include it in this study. 28 Institutional review board approval for this study was obtained from the Committee for the Protection of Human Subjects at the University of Texas Health Science Center at Houston with number HSC-SPH-17-0368. Parents of youth provided informed written consent and youth provided verbal assent. Young adults provided informed written consent.
Participants
All participants were never users of each TP at wave 2 (2014-2015) and provided complete information on tobacco use at waves 3-5 (2015-2019). Those who answered “don’t know” or refused” to answer e-cigarettes, cigarettes, or hookah use questions were excluded. Because of the difference in developmental ages, we used the CDC definitions for young teens as 12-14 years of age 29 and teenagers as 15-17 years of age 30 . While young adulthood is typically characterized as 18-25 year olds 31 , we limited our young adult sample to 18-20-year-olds, because (i) PATH only asked susceptibility questions for each TP among 18-24-year-olds, and (ii) the 20 year old adults in wave 2 received the susceptibility questions in wave 5 (ie, 24 years old at wave 5).
Outcomes: 5 States of Tobacco Use
PATH questions (2014-2019) and operationalization to create mutually exclusive tobacco product (TP)* use states.
TP: represented e-cigarettes, cigarettes, or hookah, measured individually.
AAll questions included as response options “don’t know” and “refused”. If a participant answered “don’t know” or “refused” to any question at any wave they were excluded.
Balso includes traditional cigars, cigarillos, filtered cigars and smokeless tobacco.
CPATH provided a derived variable to represent past 30-day use of each TP as “yes” and “no.”
Demographic Factors
Participant age (12-20 years old), sex (male or female), race/ethnicity, household income (above or below $50,000 dollars), and parent level of education were all measured at wave 2. Questions for race/ethnicity were combined to create the following categories: Non-Hispanic White, Non-Hispanic Black, Non-Hispanic Other, and Hispanic. Categories for parent level of education were collapsed to create the following categories: less than high school, high school/General Educational Development (GED), some college/associate’s degree, and Bachelor’s degree/Master’s degree/PhD/Professional degree.
Ever use of Cigars and Smokeless Tobacco at Wave 2
Ever use of cigars and smokeless tobacco were measured at wave 2 using similar questions and categories of responses as described in Table 1 and included to characterize the youth and young adults. Because of their low prevalence, traditional cigars, cigarillos, and filtered cigars were collapsed to represent any cigar product.
Statistical Analysis
Using the sampling weights at wave 2, 9 weighted logistic regressions were estimated to determine if the age, sex or race/ethnicity of youth explained any differences between youth included and excluded in the analyses (ie, 3 age groups*3 demographic variables*3 TPs). Weighted means, percentages and standard errors are provided for demographic variables and other TP use at wave 2 to describe included participants. Never users of each TP and age group were analyzed separately for a total of 9 analyses (3 age groups*3 TPs). Among never e-cigarette users, the prevalence of ever use of cigarettes, any cigar product, hookah and smokeless tobacco at wave 2 is reported. Among never cigarette users, the prevalence of ever use of e-cigarettes, any cigar product, hookah, and smokeless tobacco at wave 2 is reported and similarly, among never hookah users, the prevalence of ever use of e-cigarettes, cigarettes, any cigar product, and hookah at wave 2 is reported. Wave 5 all waves sampling weights with their corresponding 100 balanced repeated replicate (BRR) weights and Fay’s adjustment set to .3 were used to estimate the percentage of TP use by each transition pattern of the longitudinal cohort with complete data 27 . Sankey bar diagram macros were used to graphically visualize transition patterns of tobacco use states incorporating the use of the sampling weights and BRR weights. Frequency distributions and 95% confidence intervals (CIs) of the pattern of percentages of TP use across 4 waves of data were estimated for each TP and age group in waves 2-5 (2014-2015, 2015-2016, 2016-2017, and 2018-2019). All analyses were performed in SAS 9.4-TSlevel1M6.
Results
Comparison of Included and Excluded Participants at Wave 2
Demographic characteristics of excluded and never tobacco product users of PATH b youth at wave 2.
n = sample size; N= estimated population size
aNon-Hispanic Other includes Asian, multi-race, etc.
bPATH restricted file received disclosure to publish: November 30, 2022, December 8 and 19, 2022. United States Department of Health and Human Services. National Institutes of Health. National Institute on Drug Abuse, and United States Department of Health and Human Services. Food and Drug Administration. Center for Tobacco Products. Population Assessment of Tobacco and Health (PATH) Study [United States] Restricted-Use Files. ICPSR36231-v29.Ann Arbor, MI: Inter-university Consortium for Political and Social Research [distributor], December 16, 2021. https://doi.org/10.3886/ICPSR36231.v29.
Descriptive Statistics of Included Participants at Wave 2.
PATH c youth and young adult never tobacco product users at wave 2.
n= sample size; N= estimated population size
* Non-Hispanic Other includes Asian, multi-race, etc.
! Differences between the sum of sample size in categories with the total are due to missing values.
¥ PATH restricted file received disclosure to publish: March 31 and April 8, 2022. United States Department of Health and Human Services. National Institutes of Health. National Institute on Drug Abuse, and United States Department of Health and Human Services. Food and Drug Administration. Center for Tobacco Products. Population Assessment of Tobacco and Health (PATH) Study [United States] Restricted-Use Files. ICPSR36231-v29.Ann Arbor, MI: Inter-university Consortium for Political and Social Research (distributor), December 16, 2021. https://doi.org/10.3886/ICPSR36231.v29.
Transitions Patterns Among 12-14-year Old Youth
Figure 1 shows the transition patterns of TP use among 12-14-year-old never TP users in 2014-2015 and transitioning/remaining in each state longitudinally. Panel A shows that among never e-cigarette users, 75% were non-susceptible to e-cigarette use in 2014-2015. By 2018-2019, 44% remained non-susceptible, 21% were susceptible, 14% reported ever use, 18% reported past 30-day use, and 2% reported discontinued past 30-day e-cigarette use. Panel B shows that among never cigarette users, 73% were non-susceptible to cigarette use in 2014-2015. By 2018-2019, 63% remained non-susceptible, 24% were susceptible, 7% reported ever use, 5% reported past 30-day use, and 1% reported discontinued past 30-day use of cigarettes. Panel C shows that among never hookah users, 76% were non-susceptible in 2014-2015. By 2018-2019, 67% remained non-susceptible, 26% were susceptible, 5% reported ever use, 2% reported past 30-day use, and .26% reported discontinued past 30-day use of hookah. Therefore, by 2018-2019, the highest prevalence of ever and past 30-day TP use among 12-14-year-olds was e-cigarettes. Transition patternsof tobacco product use among PATH¥ 12-14-year-old never users.
Transitions Patterns Among 15-17-year Old Youth
Figure 2 shows the transition patterns of TP use among 15-17-year-old never TP users in 2014-2015 and transitioning/remaining in each state longitudinally. Panel A shows that among never e-cigarette users, 63% were non-susceptible to e-cigarette use. By 2018-2019, 43% remained non-susceptible, 19% were susceptible, 11% reported ever use, 22% reported past 30-day use, and 5% reported discontinued past 30-day use of e-cigarettes. Panel B shows that among never cigarette users in 2014-2015, 65% were non-susceptible to cigarette use in 2014-2015. By 2018-2019, 56% remained non-susceptible, 20% were susceptible, 9% reported ever use, 11% reported past 30-day use, and 4% reported discontinued past 30-day use of cigarettes. Panel C shows that among never hookah users in 2014-2015, 63% were non-susceptible to hookah use in 2014-2015. By 2018-2019, 56% remained non-susceptible, 28% were susceptible, 9% reported ever use, 4% reported past 30-day use, and 3% reported discontinued past 30-day use of hookah. Therefore, among 15-17-year-olds, ever use and past 30-day use was highest for e-cigarettes. Transition patterns of tobacco use among PATH¥ 15-17-year-old never users.
Transitions Patterns Among 18-20-year-old Youth
Figure 3 shows the transition patterns of TP use among 18-20-year-old never TP users in 2014-2015 and transitioning/remaining in each state longitudinally. Panel A, shows that among never e-cigarette users, 62% were non-susceptible to e-cigarettes in 2014-2015. By 2018-2019, 53% remained non-susceptible, 25% were susceptible, 7% reported ever use, 10% reported past 30-day use, and 5% reported discontinued past 30-day use of e-cigarettes. Panel B, shows that among never cigarette users in 2014-2015, 64% were non-susceptible to cigarette use in 2014-2015. By 2018-2019, 60% remained non-susceptible, 20% were susceptible, 8% reported ever use, 6% reported past 30-day use, and 6% reported discontinued past 30-day use of cigarettes. Finally, panel 3C shows that among never hookah users, 59% were non-susceptible to hookah use in 2014-2015. By 2018-2019, 56% remained non-susceptible, 28% were susceptible, 9% reported ever use, 3% reported past 30-day use, and 4% reported discontinued past 30-day use of hookah. Therefore, among 18-20-year-olds, ever use was highest for hookah and past 30-day use was highest for e-cigarettes. Transition patterns of tobacco product use among PATH¥ 18-20-year-old never users.
Patterns of Tobacco Use States
Supplemental Tables (STs) 1-9 show the longitudinal transition patterns of TP use states across 2014-2019 for the 3 TPs and 3 age groups. Across all TPs and age groups, the highest percentage of transition patterns was accounted for by never users becoming susceptible (e.g., in ST1, sum of row patterns 2, 5-8, and 13-14) or going out of susceptibility (e.g., in ST1 sum of row patterns 31-32, 35-38, 44 and 47). In terms of each unique transition pattern of within TP use states, the highest percentage across all TPs and age groups was accounted for by 15-17-year-old who were non-susceptible to e-cigarettes in 2014-2015 and remained non-susceptible to e-cigarettes across all 3 waves of follow-up (e.g., in ST4 45.7% were non-susceptible to e-cigarette use in all waves). However, there was still a considerable amount of initiation of TP use and progression across all TPs and age groups. Importantly, this varied by age group.
Among 12-14-year-olds who were non-susceptible to e-cigarette use in 2014-2015 and who remained non-susceptible to e-cigarette use between 2015-2017, 12.4% became susceptible to e-cigarette use in 2018-2019 (pattern 2 in ST1), 5.4% reported initiation of e-cigarette use (pattern 3 in ST1), and 5.2% first reported past 30-day e-cigarette use (pattern 4 in ST1). Among 12-14-year-olds who were non-susceptible to cigarette use in 2014-2015 and who remained non-susceptible to cigarette use between 2015-2017, 9.2% became susceptible in 2018-2019 (pattern 2 in ST2), 1.9% reported initiation of cigarette use (pattern 8 in ST2), and 1.1% first reported past 30-day cigarette use (pattern 10 in ST2). Among 12-14-year-olds who were non-susceptible to hookah use in 2014-2015 and who remained non-susceptible to hookah use between 2015-2017, 10.2% became susceptible in 2018-2019 (pattern 2 in ST3), .9% reported initiation of hookah use (pattern 9 in ST3), and .5% first reported past 30-day hookah use (pattern 11 in ST3). Among 12-14-year-olds who were susceptible to e-cigarette use in 2014-2015 and remained susceptible to e-cigarette use between 2015-2017, 7.0% initiated e-cigarette use and 9.4% first reported past 30-day use in 2018-2019 (patterns 34 and 33 in ST1). Among 12-14-year-olds who were susceptible to cigarette use in 2014-2015, and remained susceptible to cigarette use between 2015-2017, 5.8% initiated cigarette use and 3.0% first reported past 30-day cigarette use in 2018-2019 (patterns 30 and 35 in ST2). Among 12-14-year-olds who were susceptible to hookah use in 2014-2015 and remained susceptible to hookah use between 2015-2017, 4.5% initiated hookah use and 1.0% first reported past 30-day hookah use (patterns 30 and 34 in ST3). These findings indicate that for each TP, ever use and past 30-day use in 2018-2019 were higher in those who were susceptible to each TP in 2014-2015 than in those who were non-susceptible. Similar patterns were observed for never users of each TP among 15-17 and 18-20 years old in 2014-2015.
Discussion
Across 3 age groups of youth and young adults and 3 TPs, we consistently found that e-cigarettes were the most prevalently used TP. These findings are in line with recent U.S. nationally representative research that has shown that e-cigarettes were the most widely used TP among youth and young adults from 2014 to 2021.1,8,26,32 Countries outside of the U.S. can follow the example set in this paper to come up with their own estimates for how susceptibility impacts initiation for different TPs among youth and young adults. Across all TPs and age groups, we also found that initiation of TP use by 2018-2019 was highest among those who were susceptible to each TP compared to those who were non-susceptible. These findings are in line with previous research, which has consistently found that susceptibility predicts up to 1.5 years of subsequent TP use,9-11,13 and our findings complement these results by finding the patterns where susceptibility is related to initiation after follow-up between 2015-2019. Furthermore, while susceptibility is a cognitive precursor to TP initiation, we were able to show that susceptibility is a transient characteristic that changes from year to year for many young people. In addition, we found that TP initiation occurs, even among youth and young adults who considered themselves non-susceptible. For example, 9.4% of 12-14-year-old who were susceptible at the previous 3 waves reported past 30-day e-cigarette use in 2018-2019 (as well as 3.0% for cigarettes and 1.0% for hookah). These findings indicate that there is a window of opportunity (3 years) during which prevention programs can be implemented to deter this age group for initiating use of e-cigarettes, cigarettes, and hookah. It will be important for interventionists to understand how susceptibility changes from year to year so that interventions can be implemented before youth and young adults become susceptible to TP use (see figures or supplemental tables).
While most previous research on TP susceptibility has focused on youth,9-13, 16 a previous PATH study of young adult (18-24 year old) never users who were non-susceptible to each TP in 2013-2014 found that by age 21, 16.0%, 12.6%, and 16.5%, reported onset of susceptibility to e-cigarettes, cigarettes, and hookah, respectively 33 . This is in contrast to our findings, which found that among 18-20-year-olds who were non-susceptible to each TP in 2014-2015, 6.7%, 7.4%, and 5.9% reported onset of susceptibility to e-cigarettes, cigarettes, and hookah, respectively by wave 5. The likely reason for the difference in these findings is that the previous study used survival analysis to estimate the cumulative incidence of susceptibility onset by each age, while we estimated the percentage of susceptibility onset in 18-20-year-olds overall. Our study goes beyond this previous work by measuring ever use, past 30-day use, and discontinued past 30-day use in youth and young adults who were susceptible or non-susceptible to each TP, which to our knowledge have not reported before in the literature.
While our results from 2014-2019 indicated that initiation of all TPs examined were the highest among the younger age groups (12-14 years old/middle school age; 15-17 years old/high school age) compared with young adults (18-21 years old), this seems contrary to what was previously reported after only 2 years of follow up from 2013-2016 26 among youth (12-17 years old) and young adults (18-24 years old). Several possibilities may explain this difference: (i) our study started in 2014-2015, patterns of initiation and first report of past 30-day use were reported across more years of follow-up than the previous study; (ii) the longer the time of follow-up the higher the probability of exposure; (iii) our analyses is limited to youth and young adults with complete data from wave 2 to wave 5 which were constantly responsive to the PATH study; (iv) we separated young teens from teenagers which cannot be compared exactly with the previous publication that combined 12-14-year-old with 15-17-year-old as a single age group; (v) the previous study included 18-24-year-old while our study included only 18-20 years due to the lack of assessment of susceptibility questions for 21-24-years-old across waves 3-5 (ie as they turn 25). Therefore, the results should be interpreted under these constraints.
Notably, past 30-day use in 2018-2019 was actually higher than ever use as mutually exclusive TP use categories for e-cigarettes among 12-14-year-olds 15-17-year-olds, and 18-20-year-olds, while for cigarettes past 30-day use was higher than ever use among 15-17-year-olds. It is possible that youth and young adults are not merely experimenting with these TPs, but are progressing into patterns of regular TP use. These findings are problematic because earlier ages of TP initiation are associated with daily and past 30-day use of TPs in youth. 34
We noted that TP use was highest among 15-17-year-olds, which is concerning because earlier ages of initiation are associated with increased nicotine dependence and those who start at earlier ages are less likely to quit.34-37 This is in contrast with previous research, which found that among students in grades 6-12 in the combined 2014-2016 NYTS data, the median age of first reporting ever use was 12.6 for cigarettes, 14.1 for hookah, and 14.1 years for e-cigarettes. 34 These ages are younger than the ages of our highest occurrence of initiation, which was among 15-17-year-olds. The reason for these differences is that we started with never users and followed them up longitudinally to measure initiation, while the previous study measured the recalled age of initiation among ever users. 34 However, our findings are similar to previous cross-sectional NYTS studies, which have consistently found that use of e-cigarettes, cigarettes, and hookah is highest among high school students compared to middle school students.1,32
Strengths of the study include the use of a nationally representative dataset to understand patterns of tobacco use across 3 age groups and 3 TPs, which provides detailed results of TP initiation among those who were either susceptible or non-susceptible to each TP. In addition, we were able to graphically visualize patterns of tobacco use (up to 60 unique patterns for e-cigarettes) with Sankey diagrams. The weighted prevalence of the selected state transitions between 2014-2019 will serve also to future researchers interested in estimating the impact on health effects of these tobacco products using dynamical systems models as initial probabilities in simulation models.38,39 One limitation is that we were unable to provide associations of risk factors with these transition patterns of tobacco use because lower sample sizes for some of the transition patterns observed. We will explore associated factors in another publication after carefully evaluating how to collapse the patterns. In addition, since we created mutually exclusive tobacco use states, the results cannot be compared to other publications that examine prevalence and incidence since those outcomes would encompass both ever and past 30-day users. Although we believe the transition patterns from waves 4 to 5 (December 2018- September 2021) were impacted by the implementation of the Tobacco 21 law and the COVID 19 pandemic,28,40 only until future waves are released that incorporate questions about these events, they cannot be adjusted for. Another limitation was the demographic differences between included and excluded youth and young adults in these analyses mainly due differences in the never users who answered and did not answer the susceptibility measures. However, the sociodemographic characteristics of youth excluded are presented to faciliate to understand the direction of the bias of our results.
Conclusions
This paper provides descriptive data on transition patterns of 5 tobacco use states (non-susceptible, susceptible, ever use, past 30-day use and discontinuation of past 30-day use) for 3 TPs (e-cigarettes, cigarettes and hookah) across 3 age groups (12-14, 15-17 and 18-20-years-old) and 4 waves of follow-up (2014-2019). Our findings provide strong evidence that youth and young adults who are susceptible to e-cigarettes, cigarettes, or hookah are vulnerable to initiating TP use. Importantly, 12-14 (i.e., middle school students) and 15-17-year-olds (i.e., high school students) were particularly vulnerable to e-cigarette, cigarette, and hookah use between 2014-2019. The onset and progression of different TP behaviors during these years was more common in these age groups than young adults (18-20 years old). These findings indicate that 12-14-year-old and 15-17-year-old would benefit from comprehensive intervention programs that are targeted to these age groups (i.e., interventions that are designed for young adults may not be as effective as interventions designed specifically for youth). Understanding patterns of susceptibility and TP initiation is important for interventionists and strategists, as the transition from non-susceptibility to susceptibility provides a window of opportunity in which interventions will be most effective2, 5, 7, 33. In addition, to preclude tobacco intervention from becoming a moving target, population-based strategies, education, and interventions should be comprehensive of all TPs so that TP use reduction does not drive the popularity of a different TP. Finally, the end of wave 5 data collection (November 2019) occurred before federal law changed the minimum age of tobacco sale from 18 years to 21 years old in December 2019, 40 so the findings presented here can serve as a baseline for future studies to see if TP initiation has changed by preventing unlawful access to these TPs, as well as the effect of the COVID 19 pandemic. 28
Supplemental Material
Supplemental Material - Longitudinal Transition Patterns of Tobacco Use Among Youth and Young Adults Never Tobacco Product Users: Findings From the Population Assessment of Tobacco and Health Study, 2014-2019
Supplemental Material for Longitudinal Transition Patterns of Tobacco Use Among Youth and Young Adults Never Tobacco Product Users: Findings From the Population Assessment of Tobacco and Health Study, 2014-2019 by Meagan A. Bluestein, Arnold E. Kuk, Melissa B. Harrell, Baojiang Chen, Emily T. Hébert and Adriana Pérez in Tobacco Use Insights
Footnotes
ORCID iDs
Declaration of Conflicting Interests:
The authors have no conflicts of interest to disclose except Dr. Harrell is a consultant in litigation involving the vaping industry.
Funding:
Research reported in this publication was supported by grant number [R01CA234205] from the National Institutes of Health (NIH) - National Cancer Institute (NCI) and the Food and Drug Administration FDA Center for Tobacco Products (CTP) to Dr. Adriana Pérez. The content is solely the responsibility of the authors and does not necessarily represent the official views of NIH or FDA/CTP.
Supplemental Material:
Supplemental material for this article is available online.
References
Supplementary Material
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