This project aims to address the need for robust, rigorous and computationally efficient methods for optimizing Just-In-Time Adaptive Interventions (JITAIs) to prevent and treat substance use disorders (SUD). Although the proposed methods are motivated by micro randomized trials (MRTs) in SUD, they can be extended to observational studies and employed to develop effective JITAIs in other health domains as well. The methods developed in this project will help SUD scientists to more effectively leverage emerging technologies (e.g., mobile and wearable devices) to deliver support in a timely and ecological manner.

Alcohol problems are prevalent in young adulthood, with one in ten young adults meeting criteria for alcohol use disorder (AUD). It is therefore essential to identify and respond to risk factors for alcohol misuse during this developmental period. One underappreciated risk factor for the development of problematic drinking is the social context in which young adults consume alcohol. Recent reviews have demonstrated that young people who engage in solitary alcohol use (compared to their social-only drinking peers) are at increased risk for alcohol problems and a host of negative psychosocial outcomes (e.g., increased negative affect, aggression). Importantly, several prospective studies have demonstrated that solitary alcohol use is an independent and robust early risk marker for AUD. Despite the known risks, critical information about young adult solitary alcohol use remains unknown. Large national samples are needed to provide estimates of prevalence and historical change in young adult solitary alcohol use, as well as information on developmental changes in solitary alcohol use across young adulthood and risk factors associated with solitary alcohol use. This study will be the first to provide such information using self-report data on solitary alcohol use collected from the national Monitoring the Future study in 1976 to 2023 from those aged 18-30. We aim to (1) estimate the prevalence of young adult solitary alcohol use by age and examine the historical trends from 1976-2023, including during the COVID-19 pandemic, (2) model developmental trajectories of solitary alcohol use across young adulthood, and determine whether certain trajectories differentially predict age 35 AUD symptoms, and (3) identify risk factors associated with young adult solitary alcohol use, and determine whether associations between risk factors and solitary alcohol use change across young adulthood. Findings from this study will inform knowledge about young adult solitary alcohol use and associated risk factors and speak to the optimal timing for delivering interventions aimed at reducing solitary alcohol use and, ultimately, AUD.

High-intensity drinking (consuming 10+ drinks in a row) among young adults has recently been acknowledged as a serious health problem that requires urgent research attention. We have previously documented prevalence, predictors, and developmental change in recollection of any past 2-week high-intensity drinking from ages 18 to 30 through secondary data analysis of the national Monitoring the Future (MTF) study.

We are now collecting intensive longitudinal data to examine occasion-specific predictors and consequences of binge and high-intensity drinking at the period of the lifespan (ages 19-22) where alcohol use is the greatest. Information on occasion-specific predictors and short- and long-term consequences of binge and high-intensity drinking is needed to identify the motives, contexts, and public health impacts that differentiate these heavy levels of alcohol consumption. Building on our recent findings that used biennial data from the nationally representative Monitoring the Future (MTF) study, we plan to conduct new primary longitudinal data collection from a national sample of high school students followed into young adulthood. We will select participants from the 2018 MTF 12th-grade baseline surveys (with an oversample of high school binge drinkers) for a 4-year web-based measurement burst study – a shorter term study within a longitudinal study – across the transition into young adulthood.

We will collect up to 56 days of data per respondent using four annual data collection bursts (14 consecutive days of daily surveys per year at ages 19, 20, 21, and 22). Specific aims are to examine:

1. When and for whom high-intensity drinking is most likely to occur. We will focus on occasion-level predictors (e.g., affect, motives for drinking, drinking contexts, and other substance use) and time-varying developmental predictors (e.g., college attendance, employment, living with parents) of gender-specific rates of high-intensity drinking (8+/10+ drinks for women/men), compared to binge (4-7 for women, 5-9 for men) or moderate (1-3 for women, 1-4 for men) drinking occasions;
2. Whether acute consequences (e.g., blackouts, injury, aggressive behavior, sexual risk, and negative interpersonal consequences) associated with high-intensity (compared to moderate and binge) drinking differ across days and based on developmental and sociodemographic characteristics; and
3. Longer- term patterns of alcohol-related consequences (ages 18-22) and whether they differ by gender and social roles including educational experiences (e.g., 2-year and 4-year college).

The project will be the first national study of both college attenders and non-attenders to identify occasion-level predictors and occasion-level consequences of specific occasions of binge and high-intensity drinking. This will provide critical information for health promotion and intervention efforts targeting high-risk alcohol behaviors among young adults.

Smoking cessation decreases morbidity and mortality and is a cornerstone of cancer prevention. The ability to impact current and future vulnerability (e.g., high risk for a lapse) in real-time via engagement in self-regulatory activities (e.g., relaxation techniques, behavioral substitution, mindful attention) is considered an important pathway to quitting success. However, poor engagement represents a major barrier to maximizing the impact of self-regulatory activities. Hence, enhancing real-time, real-world engagement in evidence-based self-regulatory activities has the potential to improve the effectiveness of smoking cessation interventions. Just-In-Time Adaptive Interventions (JITAIs) are suites of intervention strategies that adapt over time to an individual?s changing status and are optimized to provide appropriate intervention strategies based on real time, real world context. Extant literature on JITAIs emphasize the importance of minimizing disruptions to the daily lives and routines of the individual, by offering an intervention based on both vulnerability (e.g., at high risk for lapse) and receptivity (i.e., an individual?s ability and willingness to utilize a particular intervention). Although both vulnerability and receptivity are considered latent states that are dynamically and constantly changing based on the constellation and temporal dynamics of emotions, context, and other factors, no attempt has been made to systematically investigate the nature of these states, as well as how knowledge of these states can be used to decide when and how to intervene. We propose to investigate (a) how the temporal dynamics and interactions of emotion, context, and self-regulatory control (SRC) can be used to detect states of vulnerability to a lapse and states of receptivity to self-regulatory activities; and (b) how knowledge of these states can be used to optimize engagement in self-regulatory activities. This will be done by analyzing intensive longitudinal self-reported and sensor-based measures of affect, SRC and context from 5 studies (3 completed and 2 ongoing) of smokers attempting to quit. The data will be used to identify (Aim 1) states of vulnerability, and (Aim 2) states of receptivity. Additionally, we propose to conduct a study with 150 smokers attempting to quit who will be offered a collection of brief, evidence-based self-regulatory activities on their mobile device. A Micro-Randomized Trial (MRT) design will be utilized to randomize each individual multiple times per day to either (a) no prompt; (b) a prompt encouraging engagement in brief (low effort) strategies; or (c) a prompt encouraging a more effortful practice of self-regulation strategies via a mobile app. The data will be used to (Aim 3) investigate whether, what type, and under what conditions (e.g., current state of vulnerability and/or receptivity) a recommendation to engage the individual in self-regulatory activities increases engagement and reduces vulnerability. The proposed research will be the first to yield a comprehensive conceptual, technical, and empirical foundation necessary to develop effective JITAIs for smoking cessation based on dynamic, personalized models of vulnerability and receptivity.

The treatment of drug use and HIV often requires sequential, individualized decision-making concerning the type or delivery of treatment. An adaptive intervention is a treatment design that uses ongoing information from the patient to guide whether, and how to modify the treatment over time. By providing the appropriate treatment to those who need it, when they need it, adaptive interventions hold the promise of improving long-term outcomes for greater numbers of people, thereby increasing the reach and impact of drug use and HIV treatments in real-world settings. The sequential multiple assignment randomized trial (SMART), a major step forward in the science of adaptive interventions, is an experimental design explicitly for identifying and constructing efficacious adaptive interventions. However, in order to make the SMART maximally useful to drug use and HIV intervention scientists, methodological work is needed to expand the options for analyzing data that arise from a SMART, which are limited in important ways. In particular, modern longitudinal data analysis methods that are used by the great majority of studies in today?s drug use and HIV research do not accommodate and cannot be used to take advantage of the unique features of a SMART, hence their application can lead to greatly reduced statistical power or even incorrect conclusions. This makes it impossible for investigators using SMARTs to scientifically benefit from the power, elegance, and nuance afforded by longitudinal data. Our objective is to bridge this critical gap by developing and evaluating new multilevel methods for analyzing longitudinal continuous, binary, and zero-inflated drug-use and HIV outcome measures arising from a SMART; developing new sample size calculators for planning SMART studies with longitudinal continuous, binary or zero-inflated outcome measures; applying and illustrating these methods using data from three SMART studies in drug abuse and HIV; and developing free, user-friendly resources to implement these methods. The methods developed in this project will improve clinical and public health outcomes by enabling drug use and HIV scientists to develop more potent adaptive interventions to guide the individualization of drug use and HIV treatments.

Monitoring the Future (MTF) study is an ongoing epidemiological and etiological research and reporting project that began in 1975. In addition to being a basic research study, MTF has become one of the nation’s most relied upon sources of information on emerging trends in illicit drug, alcohol, and tobacco use among American adolescents, college students, and young and middle-aged adults. Nationally representative samples of 8th-, 10th-, and 12th-grade students (about 16,000 in 140 schools per year per grade) will be surveyed annually from 2013 to 2017. A companion study continues mail follow-up surveys of high school graduates at modal ages 19-30, 35, 40, 45, 50, and now 55. The study’s cohort-sequential longitudinal design permits the measurement and differentiation of three types of change: age (developmental), period (historical), and cohort. The study allows examination the importance of many hypothesis on psychological, behavioral, and social determinants of drug use (including attitudes and beliefs, counter-advertising, role-modeling, and access), as well as a range of potential consequences (including physical and psychological health, status attainment, role performance, and drug abuse and dependence).

Megan Patrick’s published research focuses on the development of substance use and consequences across the lifespan. Her interests include motivations for substance use, the prevention of health risk behaviors, statistical methods for modeling behavior and behavior change, and mobile and web-based survey methodology. She has been the PI of 10 NIH-funded projects and Co-Investigator on many others. She is the Principal Investigator of the Monitoring the Future Panel Study, which is a national study following participants from ages 18 to 65 since the mid-1970s. Her other current NIH-funded R01 projects focus on high-intensity drinking, simultaneous alcohol and marijuana use, and adaptive interventions to reduce consequences of young adult substance use.

Dr. O’Malley received his Ph.D. degree in Psychology from the University of Michigan in 1975. His primary affiliation is with the Monitoring the Future study, funded by the National Institute on Drug Abuse. He is also affiliated with the Youth, Education, and Society study funded by the Robert Wood Johnson Foundation. His publications deal with alcohol, tobacco, and illicit drug use and related attitudes and beliefs, and with obesity among secondary school students. His research interests include causes and consequences of drug use, driving under the influence of alcohol or drugs, social epidemiology of drug use, school policies and practices related to student health, and longitudinal survey data analysis techniques.

Dr. Johnston’s research has been based on two seminal national research studies: Monitoring the Future: A Continuing Study of the Lifestyles and Values of American Youth (MTF) and the Youth, Education, and Society (YES) study, funded by the National Institute on Drug Abuse and the Robert Wood Johnson Foundation, respectively. MTF is an epidemiological study that reports current levels and trends in the use of a wide range of substances, from cigarettes and alcohol to marijuana, cocaine, heroin, and many other illicit drugs. Its design allows researchers to address age, cohort, and period effects on the use of these substances. Johnston and his collaborators have played an agenda-setting function by calling attention early to problems that are emerging and ones that are receding among youth. They also have demonstrated how particular attitudes and beliefs about each drug play a major role in young peoples’ use of the drug, which has helped to guide a great deal of the nation’s drug and alcohol prevention strategy.

Dr. Miech is the principal investigator of the NIDA-funded Monitoring the Future study. He received his Ph.D. degree in Sociology from the University of North Carolina at Chapel Hill and a MPH degree from Johns Hopkins University. His work focuses on trends in substance use, with an emphasis on disentangling how these trends vary by age, historical period, and birth cohort membership. Other research interests include identification of the factors that widen or narrow disparities in substance use over historical time, as well as the causes and consequences of substance use over the life course.