I am what I am: A meta-analysis of the association between substance user identities and substance use-related outcomes.

OBJECTIVE: Research indicates that a substance user identity (i.e., drinking, smoking, and marijuana identity) is positively correlated with substance use-related outcomes (e.g., frequency, quantity, consequences, and disorder symptoms). The current study aimed to meta-analytically derive single, weighted effect size estimates of the identity-outcome association as well as to examine moderators (e.g., substance use type, explicit/implicit assessment, demographic characteristics, and research design) of this association. METHOD: Random effects meta-analysis was conducted on 70 unique samples that assessed substance user identity and at least one substance use-related outcome (frequency, quantity, consequences, and/or disorder symptoms), and provided the necessary information for effect size calculations. RESULTS: Substance user identity was found to be a statistically significant moderate-to-large correlate of all substance use-related outcomes examined in the current study (r w = .365, p < .001, rw² = .133). The strongest associations were observed between identity and disorder symptoms (alcohol) and frequency of substance use (tobacco or marijuana). In terms of moderators of the identity-outcome association, the link between explicit drinking identity and alcohol use-related outcomes appeared to be stronger in magnitude than the relationship between implicit drinking identity and alcohol use-related outcomes; however, this difference appears to be largely due to the finding that implicit measures have lower reliability. The strongest identity-outcome association was observed among younger individuals. CONCLUSIONS: Substance user identity is clearly an important correlate of substance use-related outcomes and this association is stronger among younger individuals. Additional theoretical, empirical, and intervention research is needed to utilize knowledge gleaned from the current study on the identity-outcome association. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

A novel approach to assess descriptive and injunctive norms for college student marijuana use.

Descriptive and injunctive norms are traditionally assessed using different metrics. Following an innovation in the alcohol field, we examined a novel measure of perceived descriptive and injunctive marijuana norms (i.e., Marijuana Norms Grid, MNG) to characterize how these normative perceptions relate to one's own use of marijuana. The present study addressed three research questions: (1) Do college students overestimate descriptive/injunctive marijuana norms of typical college students and close friends? (2) Are descriptive/injunctive norms uniquely related to marijuana frequency and quantity? (3) Are injunctive norms related to marijuana frequency and quantity above and beyond how injunctive norms are traditionally assessed? College students (n = 7000) were recruited from 9 universities throughout the US, including 2077 past month marijuana users. Participants completed an online, cross-sectional survey that included measures assessing marijuana use, marijuana consequences, and descriptive and injunctive marijuana norms using traditional and novel assessments, among other assessments. The results revealed robust self-other discrepancies using the MNG such that participants overestimated how often and how much college students use marijuana. We also found that both descriptive and injunctive norms related uniquely to one's own marijuana use. The MNG injunctive norms explained about 19% of additional variability in marijuana outcomes beyond injunctive norms assessed using the traditional method. The findings of the present study support the utility of the novel assessment of injunctive marijuana norms. Implications for norms-based interventions are discussed.

Is marijuana identity associated with marijuana use and consequences? An examination of direct and interactive associations.

BACKGROUND: There is relatively little research examining the relationship between identity and marijuana-related outcomes (e.g., marijuana use and consequences). Identity may both directly help shape marijuana use behaviors and moderate the influence of other risk factors on marijuana outcomes. OBJECTIVES: The current study examines the relationship between marijuana identity and marijuana-related outcomes among emerging adults and explores whether identity moderates the relationships between nonidentity correlates (e.g., perceived norms and negative affect) of marijuana-related outcomes. METHODS: College students who reported marijuana use in the past 12 months completed measures of marijuana identity, perceived norms, negative affect, frequency of marijuana use, and marijuana consequences. Conclusions/Importance: The results indicated that marijuana identity is associated with marijuana use frequency and moderates the relationship between perceived norms and marijuana consequences. The findings have implications for both identity-based and social norms-based interventions targeting problematic marijuana use among emerging adults.

Alcohol, tobacco, and marijuana expectancies as predictors of substance use initiation in adolescence: A longitudinal examination.

Outcome expectancies have been found to be predictive of substance use. While development of expectancies may be dynamic during adolescence, it is unknown whether the rate of change (slope) in substance use expectancies is a risk factor for use onset across multiple substance use domains. The present study tested the hypothesis that the slope of positive and negative alcohol, tobacco, and marijuana use expectancies during mid-adolescence (9th-10th grade) would predict use onset of each respective substance during late adolescence (11th-12th grade). Data from 3,396 ethnically diverse high school students were collected across eight waves of assessment and analyzed within a latent growth modeling framework. Results revealed that the slopes of positive substance use expectancies among never-users of each respective substance predicted increased odds of onset (Alcohol: ORB = 7.73, p < .001; Tobacco: ORB = 5.58, p < .001; Marijuana: ORB = 2.49, p = .001). Only the slope of negative marijuana expectancies predicted increased odds of onset (Marijuana: ORB = .44, p = .04). Baseline level of positive and negative substance use outcome expectancies were also generally found to be associated with onset. For three common drugs used by adolescents, change in substance use expectancies during the first two years of high school may be a marker of risk propensity for substance use onset. Change in expectancies may be an important target in substance use prevention, with research indicating that expectancy challenge and life skills interventions being potentially efficacious. (PsycINFO Database Record (c) 2019 APA, all rights reserved).