Building on a Sequential Mixed-Mode Research Design in the Monitoring the Future Study.

Given the promise of the web push plus e-mail survey design for providing cost-effective and high-quality data (Patrick et al. 2018, 2019) as an alternative to a paper-and-pencil mailed survey design for the longitudinal Monitoring the Future (MTF) study, the current study sought to further enhance the web push condition. The MTF sample is based on US nationally representative samples of 12th grade students surveyed annually. The MTF control group for the current study included participants who completed the in-school baseline survey in the 12th grade and were selected to participate in their first follow-up survey in 2017 via mailed surveys (N = 1,222). A supplementary sample (N = ∼2,450) was assigned to one of the two sequential mixed-mode conditions. Those in condition 1 (N = 1,198), or mail push, were invited to complete mailed surveys and later given a web survey option. Those in condition 2 (N = 1,173), or enhanced web push, were invited to complete a web survey (the same as in the 2014 study, but with the addition of text messages and quick response (QR) codes and the web survey was optimized for mobile devices) and then later given a mailed survey option. Research aims were to examine response rates across conditions, as well as how responses were distributed across mode (paper, web), devices (computer, smartphone, table), and method of accessing the web survey (hand-entered URL, QR code, e-mail link, SMS link). Response rates differed significantly: the MTF control group was 34.2 percent, mail push was 35.4 percent, and enhanced web push was 42.05 percent. The higher response rate in the enhanced web push condition suggests that the additional strategies were effective at bringing in more respondents. Key estimates produced by the enhanced web push condition did not differ from those of the MTF control group.

Self-reported perceived negative consequences of marijuana use among U.S. young adult users, 2008-2019.

PURPOSE: This study estimated self-reported perceived negative marijuana use consequences among a national sample of U.S. young adults, examining consequence prevalence differences by use frequency, college attendance, living situation, employment, sex, and race/ethnicity; and use frequency/sociodemographic characteristic interactions. METHODS: A subsample of 1,212 respondents from the 2004-2018 class cohorts of 12th grade students participating in the nationally-representative Monitoring the Future study was surveyed up to two times from modal ages 19 through 22 (in 2008-2019). Respondents self-reported negative consequences related to their own past 12-month marijuana use. Bivariate and multivariable models examined subgroup differences in consequence prevalence. RESULTS: Approximately 60% of those using frequently (20+ use occasions in the past 30 days) and 35% of those using non-frequently reported negative consequences. Among all young adult marijuana users, 31.1% reported emotional/physical consequences, 12.9% performance/financial consequences, and 12.3% relational consequences. Use frequency was positively associated with consequence likelihood, excluding regret and unsafe driving. Among college students, frequent use was more strongly associated with any and performance/financial consequences. Controlling for use frequency, men reported more performance/financial consequences; relational consequences were higher among Hispanic (vs. White) respondents, and those living with parents, employed full-time, and not attending 4-year colleges. CONCLUSION: Young adults using marijuana reported a wide range of negative use consequences; likelihood of most consequences increased with higher use frequency. Perceived consequences varied by college attendance, living situation, employment, sex, and race/ethnicity. Efforts to reduce negative marijuana consequences may be strengthened by recognizing and addressing the different types of negative consequences users perceive.

Diversion of Medical Marijuana to Unintended Users Among U.S. Adults Age 35 and 55, 2013-2018.

OBJECTIVE: This study estimated the percentage of age 35 and 55 adults reporting using medical marijuana intended for someone else (diverted use) and compared demographics and health status of such users with respondents reporting recommended use (i.e., individuals with a medical marijuana recommendation for their own health conditions) and to respondents using marijuana not intended for medical use (nonmedical marijuana [NMM] use). METHOD: Cross-sectional analyses were conducted using complex sample survey data collected from 2013 to 2018 from 12,138 adults (6,998 women) at modal ages 35 or 55 participating in the U.S. national Monitoring the Future study. RESULTS: Diverted use was reported by 72.9% [95% CI, 66.4, 79.4] and 64.3% [56.0, 72.7] of age 35 and 55 past-12-month medical marijuana users, respectively. Age 35 diverted users were more likely than recommended users to not work full time and have no postsecondary education. Age 55 recommended users were more likely than NMM users to be retired. Age 35 diverted users were less likely than recommended users to report poor physical health (odds ratio [OR] = 0.40 [0.17, 0.94]). Age 55 diverted users were less likely than recommended users to report three or more poor health conditions (OR = 0.22 [0.09, 0.55]) and any qualifying conditions (OR = 0.21 [0.08, 0.58]). Prevalence of these conditions was similar between diverted and NMM users. CONCLUSIONS: Results indicated a substantial degree of nonmedical (i.e., recreational) marijuana use. Diverted and NMM users reported generally similar levels of health conditions, whereas diverted users had fewer indicators of poor health than recommended users.

Changes in the Order of Cigarette and Marijuana Initiation and Associations with Cigarette Use, Nicotine Vaping, and Marijuana Use: U.S. 12th Grade Students, 2000-2019.

This study (a) examined changes in marijuana and cigarette initiation sequencing and (b) considered implications of such changes for prevention efforts by examining associations between initiation sequencing and current adolescent substance use. Analyses used 2000-2019 cross-sectional data from the national Monitoring the Future (MTF) study (78,252 U.S. 12th grade students). Models examined trends in six distinct patterns of initiation order, and multivariable associations between order of initiation and 30-day cigarette and marijuana use prevalence, cigarette and marijuana use frequency among users, and nicotine and marijuana vaping prevalence. While the percentage of students initiating neither cigarettes nor marijuana increased, increases also were observed in marijuana-only initiation (the fastest-growing pattern) and initiation of marijuana before cigarettes; these increases were accompanied by a significant decrease in cigarette-only initiation. Cigarette use prevalence and frequency were highest among students initiating cigarettes before marijuana; marijuana use prevalence and frequency were highest among students initiating marijuana before cigarettes. Cigarette and marijuana prevalence, as well as marijuana frequency, were lowest among students initiating only a single substance. Nicotine vaping was less prevalent among students initiating a single substance versus both substances, but no significant differences were observed in nicotine vaping prevalence between those initiating only cigarettes versus only marijuana. Implications of these findings for prevention efforts are discussed in the frameworks of both the common liability model and route of administration model.

The growing transition from lifetime marijuana use to frequent use among 12th grade students: U.S. National data from 1976 to 2019.

BACKGROUND: More United States adolescents now report high-frequency marijuana use than similar use levels of alcohol or tobacco. Increased high-frequency use raises questions such as (a) is frequent use likelihood growing among adolescents who experiment with use? (b) Is such change observed equally across sex and racial/ethnic subgroups? (c) Have sociodemographic and other covariate associations with frequent use changed over time? METHODS: Data were obtained from 649,505 12th grade students participating in the cross-sectional, nationally-representative Monitoring the Future study from 1976 to 2019. Historical trends were modeled for any and frequent (20+ occasions) past 30-day marijuana use among all students and lifetime users, and lifetime user sex and racial/ethnic subgroups. Multivariable logistic regression estimates from 1989 to 1993 (lowest prevalence years) versus 2015-2019 (most recent years) were compared to examine covariate association changes with frequent use. RESULTS: Among all students, recent linear trends in any and frequent marijuana use were not significantly different from zero (0.023 [SE 0.156] and 0.036 [0.073], respectively); frequent use among lifetime users increased (0.233 [0.107], p = 0.048). Among lifetime users, the increase was stronger for male than female students, and for minority versus White students. Significant association changes with race/ethnicity, parental education, and perceived risk were observed. CONCLUSIONS: The proportion of adolescent lifetime marijuana users reporting current frequent marijuana use increased, and is now at near-record levels. Increases were particularly strong among males and minority students. There appears to be an increasing likelihood that adolescents who experiment with marijuana use may progress to frequent use.

The great decline in adolescent cigarette smoking since 2000: consequences for drug use among US adolescents.

OBJECTIVE: Adolescent cigarette smoking declined steadily and substantially from 2000 to 2018. This paper considers the potential consequences of this 'great decline' for the prevalence of other drug use among adolescents. METHODS: Data are annual, cross-sectional, nationally representative Monitoring the Future surveys of more than 1.2 million US students in 12th, 10th and 8th grades from 2000 to 2018. Analyses include trends in the past 12 months' non-medical amphetamine, tranquillisers and opioid use overall, among ever and never cigarette smokers, and projected if adolescent cigarette smoking levels had remained at 2000 levels. RESULTS: Within groups of ever and never cigarette smokers, the prevalence for each of the three substances has either changed little or overall increased in 2018 as compared with 2000. When the two groups were combined into one pool, the overall prevalence for each of the drugs declined by about half. The decline resulted from the growing group of never smokers, whose levels of non-medical drug use over the study period were at least four times lower than the levels of ever smokers. CONCLUSIONS: The results support the 'gateway' prediction that declines in cigarette smoking among adolescents pull downward their non-medical use of amphetamines, tranquillisers and opioids. Continuing to reduce adolescent smoking through policy and programmatic prevention efforts should have further positive spillover effects on adolescent drug use.

Two-Year Follow-up of a Sequential Mixed-Mode Experiment in the U.S. National Monitoring the Future Study.

This study examines the two-year follow up (data collected in 2016 at modal age 21/22) of an original mixed-mode longitudinal survey experiment (data collected at modal age 19/20 in 2014). The study compares participant retention in the experimental conditions to retention in the standard Monitoring the Future (MTF) control condition (participants who completed an in-school baseline survey in 12th grade in 2012 or 2013 and were selected to participate in the first follow-up survey by mail in 2014, N=2,451). A supplementary sample who completed the 12th grade baseline survey in 2012 or 2013 but were not selected to participate in the main MTF follow-up (N=4,950) were recruited and randomly assigned to one of three experimental conditions: 1: Mail Push, 2: Web Push, 3: Web Push + Email in 2014 and again in 2016. Results from the first experiment indicated that Condition 3 (Web Push + Email) was promising based on similar response rates and lower costs (Patrick et al. 2018). The current study examines how experimental condition and type of 2014 response were associated with response in 2016, the extent to which response mode and device type changed from 2014 to 2016, and cumulative cost comparisons across conditions. Results indicated that responding via web in 2014 was associated with greater odds of participation again in 2016 regardless of condition; respondents tended to respond in the same mode although the "push" condition did move respondents toward web over paper; device type varied between waves; and the cumulative cost savings of Web Push + Email grew larger compared to the MTF Control. The web push strategy is therefore promising for maintaining respondent engagement while reducing cost.

The national prevalence of adolescent nicotine use in 2017: Estimates taking into account student reports of substances vaped.

INTRODUCTION: This study presents the first nationally-representative estimates of adolescent nicotine prevalence that take into account adolescent reports of substances vaped. These reports allow nicotine estimates that consider the impact of the newly-emerged group of adolescents who report vaping only non-nicotine substances such as flavoring and/or marijuana and do not use nicotine in any form - a group typically treated as nicotine users. METHODS: Data come from Monitoring the Future and are a randomly-selected subsample of 2231 U.S. 12th grade students who answered surveys with detailed questions on tobacco use and vaping in 2017. RESULTS: Among 12th grade students 24.7% used nicotine in the last 30 days. This estimate does not include the 3.8% of students who vaped only non-nicotine substances and did not use nicotine in any other form. These students more closely resemble their peers who do not use nicotine than those who do, in terms of perceived risk and disapproval of cigarettes, as well as percentage of friends who use cigarettes. CONCLUSIONS: A decline in nicotine prevalence was statistically significant, but not strikingly large, after taking into account students who vape non-nicotine substances and do not use nicotine in any form. These students are largely similar to their peers who do not use nicotine, which underscores the importance of efforts to alert youth that they may be vaping nicotine unknowingly, and prevent them from doing so.

Increasing marijuana use for black adolescents in the United States: A test of competing explanations.

AIMS: In the last decade the relatively lower levels of marijuana use for black relative to non-black high school seniors has grown smaller and disappeared, drawing to a close a unique disparity that actually favored a disadvantaged group for at least thirty years. In this study we test trends in cigarette smoking and religiosity as possible explanations for this closing disparity. The study also examines whether increasing marijuana levels for black adolescents is better characterized as a cohort effect or an historical period effect. DESIGN: Analyses use relative risk regression and focus on data from yearly, cross-sectional surveys from the time period 2008-2017. SETTING AND PARTICIPANTS: Data comes from the nationally-representative Monitoring the Future survey, which conducts in-school surveys of secondary school students. The analysis uses data from 114,552 high school seniors (in 12th grade), 123,594 in 10th grade, and 136,741 in 8th grade. FINDINGS: Past 12-month marijuana prevalence significantly increased for black as compared to non-black adolescents from 2008 to 2017 in 12th grade, 10th grade, and 8th grade. The increase attenuated by more than half and was not statistically significant after adjusting for cigarette smoking. In contrast, the increase was little changed after adjusting adolescent levels of religiosity. The increase is better characterized as a cohort effect than a period effect. CONCLUSIONS: These results support the increase in marijuana use for black relative to non-black adolescents as an unexpected consequence of the great decline in adolescent cigarette smoking, which has occurred slower for black adolescents.

Young adult longitudinal patterns of marijuana use among US National samples of 12th grade frequent marijuana users: a repeated-measures latent class analysis.

BACKGROUND AND AIMS: Long-term frequent marijuana use is associated with significant negative outcomes, yet little is known about the longitudinal course of marijuana use among those who start frequent use during adolescence. Objectives are (a) to identify latent patterns of within-person marijuana use from ages 19-30 years among 12th graders reporting frequent marijuana use, (b) to examine if membership in identified patterns has changed across historical time and (c) to examine if key covariates differentiate class membership. DESIGN, SETTING, PARTICIPANTS: Longitudinal, national US panel data from 4423 individuals [53.4% of the eligible sample; 2744 (62%) males] who reported frequent marijuana use in 12th grade (modal age 18 years; senior year cohorts 1976-2006) followed biennially from ages 19/20 to 29/30. MEASUREMENTS: Self-reported past 30-day marijuana use (frequent use defined as use on 20+ occasions), demographics, college graduation, marriage and parenthood. FINDINGS: Repeated-measures latent class analysis (RMLCA) identified five latent classes of past 30-day marijuana use from ages 19/20 to 29/30: continued frequent users (estimated membership 23.4%); frequent to non-frequent users (15.5%); consistent non-frequent users (18.4%); non-frequent users to discontinuers (19.5%); and discontinuers (23.2%). In multivariable models, membership in the highest-risk latent class (continued frequent users) versus one or more of the lower-risk latent classes was more likely for recent cohorts (P = 0.038 to <0.001), as well as those who did not marry (P = 0.039 to < 0.001) or become parents (P = 0.001) by modal age 29/30. CONCLUSIONS: Nearly one in four 12th grade (modal age 18 years) frequent marijuana users in the US continues to report high frequency use to age 30; the proportion continuing high frequency use across young adulthood has increased among more recent cohorts.

The end of convergence in developmental patterns of frequent marijuana use from ages 18 to 30: An analysis of cohort change from 1976-2016.

BACKGROUND: This study examines the extent to which the developmental pattern of frequent marijuana use prevalence from ages 18 to 30 (overall and by gender) has varied across historical time (cohort groups) using data from a national sample of US young adults. METHODS: Self-reported data on frequent marijuana use (use on 20+ occasions in the past 30 days) from modal ages 18 to 30 were obtained from 58,059 individuals from 29 sequential cohorts (graduating high school classes of 1976-2004) participating in the Monitoring the Future study. Time-varying effect modeling was used to model cohort group differences in developmental patterns of frequent use overall and by gender. RESULTS: Developmental patterns of frequent marijuana use prevalence varied meaningfully across cohort groups. Frequent use at age 18 differed significantly across cohort groups as expected based on national data. Among earlier cohort groups (reaching age 30 during 1987-2008), developmental patterns converged by age 30 to relatively low frequent marijuana use prevalence. In contrast, among cohort groups reaching age 30 during 2008-2016, frequent marijuana use at age 30 was significantly higher than all previous cohort groups. Observed cohort differences did not vary significantly by gender. CONCLUSIONS: Cross-cohort convergence in developmental patterns of frequent marijuana use prevalence by age 30 was not observed among recent cohort groups, among whom age 30 frequent marijuana use prevalence was at the highest levels observed since the study began. Higher frequent marijuana use prevalence in late young adulthood has meaningful health risk and service provision implications.

A Sequential Mixed-Mode Experiment in the U.S. National Monitoring the Future Study.

The national Monitoring the Future (MTF) study examines substance use among adolescents and adults in the United States and has used paper questionnaires since it began in 1975. The current experiment tested three conditions as compared to the standard MTF follow-up protocol (i.e., MTF Control) for the first MTF follow-up survey at ages 19/20 years (i.e., one or two years after high school graduation). The MTF Control group included participants who completed in-school baseline surveys in the 12th grade in 2012-2013 and who were selected to participate in the first follow-up survey in 2014 (n = 2,451). A supplementary sample of participants who completed the 12th grade baseline survey in 2012 or 2013 but were not selected to participate in the main MTF follow-up (n = 4,950) were recruited and randomly assigned to one of three experimental conditions: (1) Mail Push, (2) Web Push, (3) Web Push + E-mail. Results indicated that the overall response rate was lower in Condition 2 compared to MTF Control and to Condition 1; there were no differences between Condition 3 and other conditions. Web response was highest in Condition 3; among web responders, smartphone response was also highest in Condition 3. Subgroup differences also emerged such that, for example, compared to white participants, Hispanics had greater odds of web (versus paper) response and blacks had greater odds of smartphone (versus computer or tablet) response. Item nonresponse was lowest in the Web Push conditions (compared to MTF Control) and on the web survey (compared to paper). Compared to MTF Control, Condition 3 respondents reported higher rates of alcohol use in the past 30 days. The total cost was lowest for Condition 3. Overall, the Condition 3 Web Push + E-mail design is promising. Future research is needed to continue to examine the implications of web and mobile response in large, national surveys.

Recent rapid decrease in adolescents' perception that marijuana is harmful, but no concurrent increase in use.

BACKGROUND: National trends in adolescent's marijuana risk perceptions are traditionally used as a predictor of concurrent and future trends in adolescent marijuana use. We test the validity of this practice during a time of rapid marijuana policy change. METHODS: Two repeated cross-sectional U.S. nationally-representative surveys of 8th, 10th, and 12th-graders: Monitoring the Future (MTF) (1991-2015; N = 1,181,692) and National Survey on Drug Use and Health (NSDUH) (2002-2014; N = 113,317). We examined trends in the year-to-year prevalence of perceiving no risk of harm in using marijuana regularly, and prevalence of regular marijuana use within the previous month. A piecewise linear regression model tested for a change in the relationship between trends. Similar analyses examined any past-month use and controlled for demographic characteristics. RESULTS: Among MTF 12th-graders, the prevalence of regular marijuana use and risk perceptions changed similarly between 1991 and 2006 but diverged sharply afterward. The prevalence of regular marijuana use increased by ∼1 percentage point to 6.03% by 2015. In contrast, the proportion of 12th-graders that perceived marijuana as posing no risk increased over 11 percentage points to 21.39%. A similar divergence was found among NSDUH 12th-graders and other grades, for any past month marijuana use, and when controlling demographic characteristics. CONCLUSIONS: An increase in adolescent marijuana use has not accompanied recent rapid decreases in marijuana risk perceptions. Policy makers may consider broader prevention strategies in addition to targeting marijuana risk perceptions. Further monitoring of predictors of marijuana use trends is needed as states legalize recreational marijuana use.

Reasons for Vaping Among U.S. 12th Graders.

INTRODUCTION: Vaping has recently increased in popularity among adolescents. Little is known about heterogeneity of vapers, particularly in terms of why they vape. Identifying major subgroups of adolescent vapers by reasons for vaping is important to understand adolescent vaping behavior and to identify those most at risk for other substance use. METHODS: Monitoring Future data from 2015 and 2016 were used in a latent class analysis to identify subgroups of 12th graders based on their endorsement of 10 potential reasons for vaping. Multinomial regression with a latent class outcome was used to predict class membership. RESULTS: Three distinct classes of vapers were identified: adolescents who were (1) Vaping to Experiment (29.4%), (2) Vaping to Replace Cigarettes (7.3%), and (3) Vaping for Taste + Entertainment (63.4%). Vaping only flavors was associated with lower odds of membership and cigarette use was associated with higher odds of membership in the Vaping to Replace Cigarettes subgroup, and marijuana was associated with lower odds of membership in the Vaping to Experiment subgroup, compared with the Vaping for Taste + Entertainment subgroup. CONCLUSIONS: This study identified multiple subgroups of vapers based on reasons for vaping. Whereas a small subgroup vaped for reasons related to cigarette use, most adolescent vapers reported vaping for reasons unrelated to cigarette use. There were considerable differences in primary reasons for vaping and risk for traditional cigarette and other substance use, suggesting different intervention strategies may be needed for different subgroups of vapers.

Patterns of simultaneous and concurrent alcohol and marijuana use among adolescents.

BACKGROUND: Alcohol and marijuana are the most commonly used substances among adolescents but little is known about patterns of co-use. OBJECTIVES: This study examined patterns of concurrent (not overlapping) and simultaneous (overlapping) use of alcohol and marijuana among adolescents. METHODS: Data from US-national samples of 12th graders (N = 84,805, 48.4% female) who participated in the Monitoring the Future study from 1976 to 2016 and who used alcohol and/or marijuana in the past 12 months were used to identify latent classes of alcohol use, marijuana use, and simultaneous alcohol and marijuana (SAM) use. RESULTS: A four-class solution indicated four patterns of use among adolescents: (1) Simultaneous alcohol and marijuana (SAM) use with binge drinking and recent marijuana use (SAM-Heavier Use; 11.2%); (2) SAM use without binge drinking and with recent marijuana use (SAM-Lighter Use; 21.6%); (3) Marijuana use and alcohol use but no SAM use (Concurrent Use; 10.7%); and (4) Alcohol use but no marijuana or SAM use (Alcohol-Only Use; 56.4%). Membership in either SAM use class was associated with a higher likelihood of truancy, evenings out, and use of illicit drugs other than marijuana. SAM-Heavier Use, compared to SAM-Lighter Use, class members were more likely to report these behaviors and be male, and less likely to have college plans. CONCLUSIONS: Among 12th graders who use both alcohol and marijuana, the majority use simultaneously, although not all use heavily. Given the recognized increased public health risks associated with simultaneous use, adolescent prevention programming should include focus on particular risks of simultaneous use.

E-cigarette price sensitivity among middle- and high-school students: evidence from monitoring the future.

AIMS: We estimated associations between e-cigarette prices (both disposable and refill) and e-cigarette use among middle and high-school students in the United States. We also estimated associations between cigarette prices and e-cigarette use. DESIGN: We used regression models to estimate the associations between e-cigarette and cigarette prices and e-cigarette use. In our regression models, we exploited changes in e-cigarette and cigarette prices across four periods of time and across 50 markets. We report the associations as price elasticities. In our primary model, we controlled for socio-demographic characteristics, cigarette prices, tobacco control policies, market fixed effects and year-quarter fixed effects. SETTING: United States of America. PARTICIPANTS: A total of 24 370 middle- and high-school students participating in the Monitoring the Future Survey in years 2014 and 2015. MEASUREMENTS: Self-reported e-cigarette use over the last 30 days. Average quarterly cigarette prices, e-cigarette disposable prices and e-cigarette refill prices were constructed from Nielsen retail data (inclusive of excise taxes) for 50 US markets. FINDINGS: In a model with market fixed effects, we estimated that a 10% increase in e-cigarette disposable prices is associated with a reduction in the number of days vaping among e-cigarette users by approximately 9.7% [95% confidence interval (CI) = -17.7 to 1.8%; P = 0.02] and is associated with a reduction in the number of days vaping by the full sample by approximately 17.9% (95% CI = -31.5 to -4.2%; P = 0.01). Refill e-cigarette prices were not statistically significant predictors of vaping. Cigarette prices were not associated significantly with e-cigarette use regardless of the e-cigarette price used. However, in a model without market fixed effects, cigarette prices were a statistically significant positive predictor of total e-cigarette use. CONCLUSIONS: Higher e-cigarette disposable prices appear to be associated with reduced e-cigarette use among adolescents in the US.