Regression tree applications to studying alcohol-related problems among college students.

Machine learning algorithms hold promise for developing precision medicine approaches to addiction treatment yet have been used sparingly to identify predictors of alcohol-related problems. Recursive partitioning, a machine learning algorithm, can identify salient predictors and clinical cut points that can guide treatment. This study aimed to identify predictors and cut points of alcohol-related problems and to examine result stability in two separate, large data sets of college student drinkers (n = 5,090 and 2,808). Four regression trees were grown using the "rpart" package in R. Seventy-one predictors were classified as demographics (e.g., age), alcohol use indicators (e.g., typical quantity/frequency), or psychosocial indicators (e.g., anxiety). Predictors and cut points were extracted and used to manually recreate the tree in the other data set to test result stability. Outcome variables were alcohol-related problems as measured by the Alcohol Use Disorder Identification Test and Brief Young Adult Alcohol Consequences Questionnaire. Coping with depression, conformity motives, binge drinking frequency, typical/heaviest quantity, drunk frequency, serious harm reduction protective behavioral strategies, substance use, and psychosis symptoms best predicted alcohol-related problems across the four trees; coping with depression (cut point range: 1.83-2.17) and binge drinking frequency (cut point range: 1.5-2.5) were the most common splitting variables. Model fit indices suggest relatively stable results accounting for 17%-30% of the variance. Results suggest the nine salient predictors, particularly coping with depression motives scores around 2 and binge drinking frequency around two to three times per month, are important targets to consider when treating alcohol-related problems for college students. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Factor structure, group invariance, and concurrent validity of scores from the college eating and drinking behavior scale among U.S. college students.

Food and alcohol disturbance (FAD) refers to the intersection of alcohol- and eating-related motives and behaviors, such as restricting food intake before or during alcohol use to offset caloric intake or to enhance intoxication. Valid assessment is critical for advancing research on FAD. We tested the factor structure, group invariance, and concurrent validity of the College Eating and Drinking Behavior Scale (CEDBS) in a large college student sample (n = 2610; Mage = 20.95, SD = 4.65; 71.8% female; 77% White; 86% non-Hispanic). Participants completed measures assessing antecedents of alcohol use (i.e., protective behavioral strategies and drinking motives), negative alcohol-related consequences, alcohol use severity, and risk for eating disorder. The 3-factor model of the 21-item CEDBS provided an adequate fit to the data (e.g., CFI = 0.916). These factors include Alternative Methods (4 items; "Use laxative prior to drinking alcohol"), Offset Calories (7 items; "Restrict calories prior to drinking to help maintain your figure"), and Quicker Intoxication (10 items; "Not eating before drinking alcohol because it gives you the best buzz"). The CEDBS was scalar invariant across subgroups of participants based on age, sex, race/ethnicity, socioeconomic status, sexual orientation, and political orientation. Quicker Intoxication was most strongly related to risk factors and negative consequences for alcohol (r = 0.204-0.379, all ps < 0.01), and Offset Calories was most strongly related to risk for eating disorders (r = 0.349, p < .01). These findings further support the CEDBS to assess FAD among college students.

Measurement of the self-determination continuum of motivation for engaging in alcohol-related harm reduction behaviors: Improved content coverage of the Treatment Self-Regulation Questionnaire.

Self-determination theory (SDT) proposes that people are more likely to engage in behaviors that reduce the harms associated with alcohol use if they do so for more self-determined reasons. There is growing support for this proposal, but the Treatment Self-Regulation Questionnaire (TSRQ), which assesses the self-determination continuum of motivation for engaging in alcohol-related harm reduction behaviors, lacks content coverage. We generated additional items to improve the content coverage of the TSRQ and evaluated its psychometric properties. We also compared two randomly assigned instruction sets that referenced "responsible drinking" or "protective behavioral strategies" (PBS). Participants (n = 2,236) were college students from psychology departments at 10 universities in eight U.S. states who reported past-month alcohol use and completed the revised TSRQ; the online survey was completed for partial course credit. Exploratory factor analysis supported a three-factor structure representing autonomous motivation, controlled motivation, and amotivation for the PBS version. This factor structure was confirmed using exploratory structural equation modeling for both the PBS and responsible drinking versions. Scalar invariance was achieved across instruction sets. Latent mean differences showed that those who received the PBS version had lower autonomous and controlled motivation scores, but higher amotivation scores. Associations of the three TSRQ factors with alcohol-related outcomes were consistent with SDT, and the magnitude of these associations did not differ across instruction sets. More accurate assessment of the self-determination continuum of motivation for alcohol-related harm reduction behaviors will improve research on this topic which has promising implications for alcohol interventions. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Reductions in World Health Organization risk drinking level are associated with improvements in sleep problems among individuals with alcohol use disorder.

AIMS: Among individuals with alcohol use disorder (AUD), sleep disturbances are pervasive and contribute to the etiology and maintenance of AUD. However, despite increased attention toward the relationship between alcohol use and sleep, limited empirical research has systematically examined whether reductions in drinking during treatment for AUD are associated with improvements in sleep problems. METHODS: We used data from a multisite, randomized, controlled trial that compared 6 months of treatment with gabapentin enacarbil extended-release with placebo for adults with moderate-to-severe AUD (N = 346). The Timeline Follow-back was used to assess WHO risk drinking level reductions and the Pittsburgh Sleep Quality Index was used to assess sleep quality over the prior month at baseline and the end of treatment. RESULTS: Sleep problem scores in the active medication and placebo groups improved equally. Fewer sleep problems were noted among individuals who achieved at least a 1-level reduction (B = -0.99, 95% confidence interval (CI) [-1.77, -0.20], P = .014) or at least a 2-level reduction (B = -0.80, 95% CI [-1.47, -0.14], P = .018) in WHO risk drinking levels at the end of treatment. Reductions in drinking, with abstainers excluded from the analysis, also predicted fewer sleep problems at the end of treatment (1-level: B = -1.01, 95% CI [-1.83, -0.20], P = .015; 2-level: B = -0.90, 95% CI [-1.59, -0.22], P = .010). CONCLUSIONS: Drinking reductions, including those short of abstinence, are associated with improvements in sleep problems during treatment for AUD. Additional assessment of the causal relationships between harm-reduction approaches to AUD and improvements in sleep is warranted.

Reductions in World Health Organization Risk Drinking Level Are Associated With Reductions in Alcohol Use Disorder Diagnosis and Criteria: Evidence From an Alcohol Pharmacotherapy Trial.

OBJECTIVES: This study aimed to evaluate the validity of World Health Organization (WHO) risk drinking level reductions as meaningful endpoints for clinical practice and research. This study examined whether such reductions were associated with a lower likelihood of a current alcohol use disorder (AUD) diagnosis and fewer AUD criteria. METHODS: We conducted a secondary data analysis to address these objectives using data from a multisite randomized controlled trial of gabapentin enacarbil extended release in treating moderate to severe AUD among adults (N = 346). Participants received gabapentin enacarbil extended release or placebo for 6 months. The timeline follow-back was used to assess WHO risk drinking level reductions, and the Mini-International Neuropsychiatric Interview was used to assess Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) AUD diagnosis and criteria at baseline (past year) and end of treatment (past month). RESULTS: Most participants (80.1%) achieved at least a 1-level reduction in the WHO risk drinking levels from baseline to end of treatment, and nearly half of participants (49.8%) achieved at least a 2-level reduction. At least a 1-level reduction or at least a 2-level reduction in WHO risk drinking level predicted lower odds of an active AUD diagnosis (1-level: odds ratio, 0.74 [95% confidence interval (CI), 0.66-0.84]; 2-level: odds ratio, 0.71 [95% CI, 0.64-0.79]) and fewer AUD criteria (1-level: B, -1.66 [95% CI, -2.35 to -0.98]; 2-level: B, -1.76 [95% CI, -2.31 to -1.21]) at end of treatment. CONCLUSIONS: World Health Organization risk drinking level reductions correlate with Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) AUD diagnosis and criteria, providing further evidence for their use as endpoints in alcohol intervention trials, which has potential implications for broadening the base of AUD treatment.

Reductions in WHO risk drinking levels correlate with alcohol craving among individuals with alcohol use disorder.

BACKGROUND: Abstinence has historically been considered the preferred goal of alcohol use disorder (AUD) treatment. However, most individuals with AUD do not want to abstain and many are able to reduce their drinking successfully. Craving is often a target of pharmacological and behavioral interventions for AUD, and reductions in craving may signal recovery. Whether reductions in drinking during AUD treatment are associated with reductions in craving has not been well examined. METHODS: We conducted secondary analyses of data from three AUD clinical trials (N's= 1327, 346, and 200). Drinking reductions from baseline to the end of treatment were measured as changes in World Health Organization (WHO) risk drinking levels; alcohol craving was measured using validated self-report measures. Regression analyses tested whether drinking reductions were associated with end-of-treatment craving reductions; moderation analyses tested whether associations between drinking reduction and end-of-treatment craving differed across AUD severity. RESULTS: Reductions of at least 1 or at least 2 WHO risk drinking levels were associated with lower craving (all p's < 0.05). Results were substantively similar after removing abstainers at the end-of-treatment. Associations between drinking reductions and craving were generally not moderated by AUD severity. CONCLUSIONS: Individuals with WHO risk drinking level reductions reported significantly lower craving, as compared to those who did not achieve meaningful reductions in drinking. The results demonstrate the utility of WHO risk drinking levels as AUD clinical trial endpoints and provide evidence that drinking reductions mitigate craving.

Indirect Associations between Impulsivity and Alcohol Outcomes through Motives for Drinking Responsibly among U.S. College Students: An Integration of Self-Determination Theory and the Acquired Preparedness Model.

The aim of the present study was to conduct a preliminary investigation of the associations between facets of impulsivity and alcohol outcomes through motives for drinking responsibly described by self-determination theory among college students. Participants (N=2,808) were part of a multisite investigation of college student drinking across 10 universities in 8 states in the U.S. who reported past-month drinking. Results of a structural equation model testing all possible indirect associations simultaneously indicated that one-third (20 out of 60) of the indirect associations were statistically significant (p<.01). Facets with higher scores representing higher impulsivity (negative/positive urgency) were negatively associated with more internalized motives (autonomous motivation and introjected regulation) and positively associated with less internalized motives (external regulation and amotivation) for drinking responsibly. Facets with higher scores representing lower impulsivity (perseverance and premeditation) demonstrated opposite patterns of associations with motives for drinking responsibly. In turn, more internalized motives were related to higher frequency of protective behavioral strategies use, lower alcohol use severity, and fewer negative alcohol-related consequences; less internalized motives demonstrated an opposite pattern of associations with these alcohol outcomes. The present findings should be replicated using experimental and longitudinal studies for appropriately testing mediation but offer support for a novel hypothesis for motivational pathways from impulsivity to alcohol outcomes that may provide insight into intervention targets.

Development and validation of the Substance Use Protective Strategies Scale (SUPSS) among Polish young adults using various psychoactive substances.

Research supports protective behavioral strategies (PBS) as effective in reducing substance use, intoxication, and/or related risks/harms. However, despite the predominance of polysubstance use and common co-occurrence of different substance use disorders (SUDs), previous PBS research has been limited in terms of substance-specific measurement. This study sought to develop and validate a measure of PBS that is not substance-specific. Building from initial pilot work, we tested the psychometric properties of the Substance Use Protective Strategies Scale (SUPSS) in a large sample of young adults (N = 7325, aged 18-30), who reported using multiple psychoactive substances (other than alcohol and nicotine), recruited via social media in Poland. By splitting the sample, we conducted exploratory (n = 3709) and confirmatory factor analysis (n = 3614), which supported a 4-factor structure with 19 items (7 items dropped): Preparation for use (α = 0.66), Manner of use (α = 0.85), Additional concerns (α = 0.74), and Setting (α = 0.62). Configural, metric and scalar invariance were supported across sex, age, and user status for most substance types (cannabis, dissociatives, etc.). Further, the SUPSS factors were strongly associated with substance-related harms (R-squared = 0.495) and SUD symptoms (DUDIT, R-squared = 0.570). Our model fit was adequate (but not excellent), and two subscales had low internal consistency, highlighting the need for further improvement of the SUPSS. Despite its limitations, we found the SUPSS to have strong psychometric properties and it holds promise to enhance PBS research and harm reduction-oriented interventions.

A Cross-Cultural Comparison of Negative Alcohol-Related Consequences in the United States and Sweden: Measurement Invariance of the Rutgers Alcohol Problem Index.

Commensurate measures of alcohol-related consequences across countries and cultures are critical for addressing the global burden of hazardous alcohol use. The Rutgers Alcohol Problem Index (RAPI), developed and validated in the United States, is a popular measure of alcohol problems. This study examined measurement invariance of the RAPI across samples of U.S. and Swedish high school seniors. Latent mean differences in alcohol problems across countries and differences in associations between alcohol problems with alcohol use and protective behavioral strategies (PBS) were also examined. The RAPI was scalar invariant. Swedish students reported fewer problems than U.S. students (latent mean difference = -0.19, p = .047). In both samples, the RAPI was positively correlated with alcohol use frequency and quantity (ps < .001), and negatively correlated with PBS use (ps < .05). Overall, the RAPI demonstrated measurement invariance, and we found evidence for its validity across samples of U.S. and Swedish high school seniors.

Profiles of alcohol and cannabis protective behavioral strategies use across two large, multi-site college student samples of concurrent alcohol and cannabis users.

Concurrent use of alcohol and cannabis among college students is common and confers greater harms than the use of either of these substances alone. Large and growing bodies of literature have demonstrated the independent utility of behaviors used before, during, after, or instead of alcohol and cannabis use that minimize related harms (i.e., protective behavioral strategies [PBS]). However, little is known about the relationship between alcohol and cannabis PBS and their joint influence on harms among college students who concurrently use alcohol and cannabis. In the present study, we used data from two large, multi-site samples of college students, and restricted analyses to those who reported at least one episode of alcohol and cannabis use in the past 30 days (Study 1: N = 1104[Mage = 20.3, SD = 3.8; 70.0 % female; 79.5 % white]; Study 2: N = 2034[Mage = 20.2, SD = 3.2; 69.1 % female; 76.6 % white]). A latent profile analysis supported a 4-profile solution that was largely consistent across samples: Profile 1 (low alcohol/cannabis PBS; 8.8-11.9 %), Profile 2 (average alcohol/cannabis PBS; 33.1-37.7 %), Profile 3 (average alcohol PBS/low cannabis PBS; 16.3-25.2 %), and Profile 4 (high alcohol/cannabis PBS; 29.8-37.2 %). Profile 4 reported the least alcohol/cannabis use, fewest negative alcohol-/cannabis-related consequences, and lowest alcohol/cannabis use severity. In contrast, Profile 1 was the opposite for alcohol-related outcomes, and Profile 3 was the opposite for cannabis-related outcomes. These findings are preliminary but may suggest that targeting both alcohol and cannabis PBS in intervention is generally beneficial except some groups at risk for a particular substance may benefit from increased focus on that substance in intervention.

The influence of cognitive and affective components of the sentinel event on alcohol use following a brief intervention with trauma patients.

OBJECTIVE: Alcohol-related injury is a sentinel event, an unanticipated medical event that may prompt a re-evaluation of health behaviors, such as alcohol use. Few studies have examined the psychological components of the sentinel event that motivate behavior change. In the present study, we examined the influence of cognitive and affective components of an alcohol-related injury on changes in alcohol use following a brief intervention. METHOD: Injured patients (n = 411) who were drinking prior to their injury admission were recruited from three urban Level I trauma centers and randomized to receive brief advice or brief motivational intervention with or without a 1-month booster session. Assessments were completed at baseline and 3-, 6-, and 12-month follow-ups. Three groups were created based on endorsement (yes/no) of items assessing cognitive and affective components of the injury event: neither component, the cognitive component only, and both the cognitive and affective components. RESULTS: Mixed-effects models indicated that participants who endorsed both the cognitive and affective components had greater reductions in peak alcohol use from baseline to 3-month follow-up than those who did endorsed neither component. By contrast, participants who endorsed the cognitive component, but not the affective component, had greater increases in average drinks per week and percentage of days of heavy drinking from 3- to 12-month follow-ups than those who endorsed neither component. CONCLUSION: These results provide preliminary support for further consideration of an affective component of alcohol-related injuries that may motivate subsequent reductions in drinking following a sentinel event.

The Associations of Basic Psychological Need Satisfaction and Need Frustration with Cannabis-Related Outcomes in a Multi-Site Sample of College Students.

Psychological need satisfaction and need frustration, proposed by self-determination theory, may serve as conditions that foster health-promoting and health-impairing behaviors related to cannabis use. In the present study, we examined the measurement model of psychological need satisfaction and need frustration and their associations with cannabis protective behavioral strategies use, negative cannabis-related consequences, and cannabis use severity. Data were from 1394 college students from 10 universities across the U.S. who reported past-month cannabis use. A higher-order factor model representing general psychological need satisfaction and need frustration provided a good fit to the data. Regressing the three observed cannabis outcome variables onto these higher-order latent factors, we found that greater need satisfaction was associated with more frequent cannabis protective behavioral strategies use and fewer negative cannabis-related consequences. Greater need frustration was associated with greater negative cannabis-related consequences and cannabis use severity. Further, an interaction effect between need satisfaction and need frustration emerged for each cannabis outcome such that greater need satisfaction attenuated the associations between need frustration and cannabis outcomes and greater need frustration strengthened the associations between need satisfaction and cannabis outcomes. Implications for the roles of need satisfaction and need frustration in cannabis use and future intervention development are discussed.

Relative and Interactive Associations of Psychosocial Intervention and Alcoholics Anonymous Attendance With Alcohol Use Disorder Outcomes.

OBJECTIVE: Psychosocial intervention and Alcoholics Anonymous (AA)/mutual help organization attendance are both associated with alcohol use disorder (AUD) outcomes. However, no research has explored the relative or interactive associations of psychosocial intervention and AA attendance with AUD outcomes. METHOD: This was a secondary analysis of data from the Project MATCH (Matching Alcoholism Treatments to Client Heterogeneity) outpatient arm participants (N = 952), who were randomly assigned to complete 12-session cognitive-behavioral therapy (CBT, n = 301), 12-session 12-step facilitation (TSF, n = 335), or 4-session motivational enhancement therapy (MET, n = 316). Regression analyses tested the association of psychosocial intervention attendance only, AA attendance only (measured as past-90-day attendance immediately after psychosocial intervention, as well as 1 and 3 years after intervention), and their interaction with the percentage of drinking days and percentage of heavy drinking days after intervention, 1 year after intervention, and 3 years after intervention. RESULTS: When accounting for AA attendance and other variables, attending more psychosocial intervention sessions was consistently associated with fewer drinking days and heavy drinking days after intervention. AA attendance was consistently associated with a lower percentage of drinking days at 1 and 3 years after intervention, when accounting for psychosocial intervention attendance and other variables. Analyses failed to identify an interaction between psychosocial intervention attendance and AA attendance with AUD outcomes. CONCLUSIONS: Psychosocial intervention and AA attendance are robustly associated with better AUD outcomes. Replication studies comprising samples of individuals who attend AA more than once per week are needed to further test the interactive association of psychosocial intervention attendance and AA attendance with AUD outcomes.

A comprehensive examination of motivational profiles for alcohol-related behaviors among college students.

Recent research demonstrates unique relations of types of motivation for drinking responsibly based on self-determination theory and drinking motives with alcohol-related outcomes among college students. In the present study, we sought to extend prior research by using a person-centered approach to simultaneously consider types of motivation within and across these motivational constructs as well as their synergistic relations with alcohol-related outcomes. We used cross-sectional survey data from 2,808 college students at 10 universities in eight states across the United States who reported past-month alcohol use (Mage = 20.59, SD = 4.18; 72.9% female; 58.2% non-Hispanic White). A series of latent profile analyses were conducted using types of motivation for drinking responsibly and drinking motives as indicators. A five-profile solution was selected as optimal. Mean comparisons indicated that profiles defined by high endorsement of higher quality motivations for drinking responsibly (i.e., more self-determined) and low endorsement of drinking motives in combination were related to the most frequent protective behavioral strategies use, least alcohol use, and fewest negative alcohol-related consequences. Additionally, these profiles were higher on dispositional autonomy and psychological need satisfaction and lower on psychological need frustration. These findings provide initial insight into simultaneously considering motivational profiles for the interrelated behaviors of drinking responsibly and drinking that can be leveraged in college drinking interventions. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Measurement invariance of the University of Rhode Island Change Assessment Scale in Project MATCH: An exploratory structural equation modeling approach.

BACKGROUND: Progression through the stages of change is a proposed mechanism underlying the effects of treatment for alcohol use disorder (AUD). However, examining stages of change as a mechanism of treatment effects requires that the measure be invariant across patient subgroups, treatment conditions, and time. In this study, we examined measurement invariance of the University of Rhode Island Change Assessment Scale (URICA) in Project MATCH using an exploratory structural equation modeling (ESEM) approach. METHODS: We conducted a secondary analysis of data from Project MATCH (N = 1726; Mage  = 40.2, SD = 10.9; 75.7% male; 80% non-Hispanic white), a multisite randomized clinical trial that tested three AUD treatments: Motivational Enhancement Therapy, Cognitive-Behavioral Therapy, or Twelve-Step Facilitation. Participants completed the 24-item URICA for assessing the stages of change in relation to drinking at baseline and post-treatment (3 months after baseline). RESULTS: A 4-factor ESEM provided a good fit to the data and a better fit to the data than a conventional 4-factor confirmatory factor analysis model. Further, the URICA demonstrated scalar invariance across each patient subgroup at baseline (sex, ethnicity, marital status, education, and parental history of AUD) and treatment condition at follow-up. However, the URICA was not longitudinally invariant as the metric model resulted in a significant decrement in model fit. CONCLUSIONS: Measurement invariance of the URICA over time was not supported. Longitudinally invariant measures of the stages of change are needed to test the proposal that progression through the stages explains treatment effects.

Using Decision Trees to Identify Salient Predictors of Cannabis-Related Outcomes.

Cannabis use continues to escalate among emerging adults and college attendance may be a risk factor for use. Severe cases of cannabis use can escalate to a cannabis use disorder, which is associated with worse psychosocial functioning. Predictors of cannabis use consequences and cannabis use disorder symptom severity have been identified; however, they typically employ a narrow set of predictors and rely on linear models. Machine learning is well suited for exploratory data analyses of high-dimensional data. This study applied decision tree learning to identify predictors of cannabis user status, negative cannabis-related consequences, and cannabis use disorder symptoms. Undergraduate college students (N = 7000) were recruited from nine universities in nine states across the U.S. Among the 7 trees, 24 splits created by 15 distinct predictors were identified. Consistent with prior research, one's beliefs about cannabis were strong predictors of user status. Negative reinforcement cannabis use motives were the most consistent predictors of cannabis use disorder symptoms, and past month cannabis use was the most consistent predictor of probable cannabis use disorder. Typical frequency of cannabis use was the only predictor of negative cannabis-related consequences. Our results demonstrate that decision trees are a useful methodological tool for identifying targets for future clinical research.

Perceived discrimination and alcohol-related problems among Hispanic college students: The protective role of serious harm reduction behaviors.

The present study investigated the use of protective behavioral strategies (PBS) as moderators of the association between perceived discrimination and alcohol-related problems among Hispanic college students. Participants who were between 18 and 24 years of age (n = 379) completed self-report measures. The results showed that greater perceived discrimination was associated with less frequent PBS use, more problematic alcohol use, and more alcohol-related problems, while greater use of PBS types was associated with fewer alcohol-related problems. Furthermore, serious harm-reduction behaviors moderated the association between perceived discrimination and alcohol-related problems. The findings suggest that serious harm-reduction behaviors may protect against the negative effects of perceived discrimination on alcohol-related problems among Hispanic college students.

A Test of Interaction Effects Between Cannabis Protective Behavioral Strategies and Antecedents of Cannabis-Related Consequences.

The purpose of the present study was to examine tests of interaction effects between cannabis protective behavioral strategies use and a range of risk/protective factors for negative cannabis-related consequences. We recruited 2,226 college students (Mage = 20.28, SD = 3.37; 68.8% female; 75.4% White) from 10 universities throughout the U.S. who reported using cannabis in the past month to complete an online survey. Measures assessed cannabis use, negative cannabis-related consequences, cannabis protective behavioral strategies use, and 35 risk/protective factors (including socio-demographic characteristics). Cannabis protective behavioral strategies use was negatively correlated with negative cannabis-related consequences while including the risk/protective factors as covariates. Most importantly, 33% and 54% of the interaction effects tested were statistically significant, depending on the covariates entered into the model. The interaction effects had a consistent pattern such that the positive association between greater risk and negative cannabis-related consequences was weaker as cannabis protective behavioral strategies use increased. Findings suggest that the nature of these interaction effects is not specific for any given risk/protective factor. We draw parallels to research on alcohol protective behavioral strategies and offer suggestions for moving the cannabis protective behavioral strategies field forward.

Measurement Invariance of the Readiness to Change Questionnaire Among Injured Patients Who Received a Brief Intervention for Alcohol Use.

We tested measurement invariance of the Readiness to Change Questionnaire (RCQ) to evaluate its utility in assessing the stages of change in the context of brief intervention for alcohol use in opportunistic settings. Participants (N = 596) were patients admitted from three Level I trauma centers who were randomly assigned to one of three brief alcohol interventions. The RCQ was administered at baseline and 3-month follow-up. The RCQ was scalar invariant across biological sex and partially scalar invariant across race/ethnicity and alcohol use severity. Hispanic participants were higher on contemplation and action and Black participants were higher on action than White participants. Hazardous drinkers were lower in precontemplation and higher in contemplation and action than nonhazardous drinkers. The RCQ was scalar invariant across intervention conditions and time. Brief motivational intervention with a booster increased action from baseline to 3 month. These findings provide further support for the use of the RCQ.