The validity of DSM-IV cannabis abuse and dependence criteria in adolescents and the value of additional cannabis use indicators

Dimensionality and differential functioning of DSM-5 cannabis use disorder criteria in an online sample of adults with frequent cannabis use

The DSM-5 criteria for cannabis use disorder (CUD) combine DSM-IV dependence and abuse criteria (without legal problems) and new withdrawal and craving criteria. Information on dimensionality, internal reliability, and differential functioning of the DSM-5 CUD criteria is lacking. Additionally, dimensionality of the DSM-5 withdrawal items is unknown. This study examined the psychometric properties of the DSM-5 CUD criteria among adults who used cannabis in the past 7 days (N = 5,119). Adults with frequent cannabis use were recruited from the US general population through social media and filled in a web-based survey about demographics and cannabis use behaviors. Factor analysis was used to assess dimensionality, and item response theory analysis models were used to explore relationships between the criteria and the underlying latent trait (CUD), and whether each criterion and the criteria set functioned differently by demographic and clinical characteristics: sex, age, state-level cannabis laws, reasons for cannabis use, and frequency of use. The DSM-5 CUD criteria showed unidimensionality and provided information about the CUD latent trait across the severity spectrum. The cannabis withdrawal items indicated one underlying latent factor. While some CUD criteria functioned differently in specific subgroups, the criteria set as a whole functioned similarly across subgroups. In this online sample of adults with frequent cannabis use, evidence supports the reliability, validity, and utility of the DSM-5 CUD diagnostic criteria set, which can be used for determining a major risk of cannabis use, i.e., CUD, to inform cannabis policies and public health messaging, and for developing intervention strategies.

Smoking Mostly Alone as a Risk Factor for Cannabis Use Disorders and Depressive Symptoms

The empirically grounded etiological models of cannabis use already include a vast range of psychological factors (within an individual), paving the ground for individualized prevention and intervention programs. However, the interpersonal (among individuals) and relational variables influencing the emergence of excessive cannabis use are less understood. Particularly, the impact of consumption context (i.e., smoking alone or with others) on cannabis use intensity in youth remains to be clarified. We evaluated how smoking mostly alone modulates cannabis use disorders (CUD) and depressive symptoms in college students. A sample of 854 individuals from France (568 women, 286 men) who used cannabis in the last 6 months completed self-report questionnaires evaluating cannabis consumption, CUD symptoms, and depressive symptoms. Mostly alone users presented higher current use frequency as well as increased CUD and depressive symptoms compared to mostly social users. Smoking mostly alone remained positively correlated with CUD and depressive symptoms, even when controlling for current use frequency. The association between smoking mostly alone and depressive symptoms was significant before adjustment for symptoms of CUD. The loss of significance of this association after control reflected the mediating effects of symptoms of CUD on the relationship between smoking mostly alone and depressive symptoms. These results suggest that smoking mostly alone constitutes a risk factor for uncontrolled cannabis use and promote the relationship between cannabis use and depressive disorders, potentially through loneliness and social isolation. Longitudinal studies are required to identify the causal mechanisms underlying the links between smoking mostly alone, cannabis use and psychopathological disorders.

An exploration of multivariate symptom clusters of cannabis use disorder in young adults

AIMS

Since the release of the DSM-V, CUD has been understood as a unidimensional construct. However, continued research has identified separate symptom clusters relating to consumption, loss of control, and withdrawal within substance use disorder criteria that may pose separate risk factors and functional difficulties. The current study aims to examine how symptom clusters commonly manifest in young adults that use cannabis using a latent class analysis (LCA) and explore how these clusters are related to co-occurring psychological constructs.

METHODS

1174 (aged 18-34) participants completed a battery of assessments on substance use and other psychological constructs. LCA was conducted on 17 symptoms corresponding with DSM-V CUD criteria. Multinomial regressions were used to examine class membership and commonly co-occurring psychopathology and psychological constructs.

RESULTS

LCA results identified a 'No problems' class, a 'Moderate consumption' class characterized by moderate probability of endorsing consumption items, a 'Consumption with Moderate Loss of Control' class, characterized by endorsing consumption and loss of control items but minimal endorsement of withdrawal items, a 'Consumption with Moderate Withdrawal' class characterized by moderate probability of endorsing all item types, and 'High Consumption, Loss of Control, Withdrawal' class characterized by high probability of endorsing all items. Multinomial regressions indicated some class differences in psychological constructs.

CONCLUSIONS

Symptom clusters differed in terms of CUD criteria, especially for those in our sample with moderate/severe problems. Findings suggest intervention efforts may benefit from treatment targeted at various presentations of CUD.

Too Much Information? Excessive Media Use, Maladaptive Coping, and Increases in Problematic Cannabis Use during the COVID-19 Pandemic

During a health crisis like the COVID-19 pandemic, the public depends on the media for accurate and up-to-date information. However, frequent use of media for COVID-19-related information may be associated with maladaptive coping, and with increased prevalence of substance use. This study examined indirect associations between the frequency of media use for information about COVID-19 and increases in cannabis use behaviors through maladaptive coping strategies. We use data from an online survey of Israeli adult cannabis users (N = 440), conducted in May of 2020, to test associations between media use frequency for COVID-19 information and three problematic cannabis use behaviors: increased cannabis use, increased use alone, and increased use before midday. Among all respondents, 41% agreed that their cannabis use had increased since the onset of the pandemic. Analyses showed that higher frequency of media use was positively associated with all three indicators of problematic cannabis use, and that associations were partly mediated by maladaptive coping strategies. Higher frequency of media use for information about COVID-19 may be an indicator of difficulty with coping and of increased risk of escalation of cannabis use. These results have implications for assessing and mitigating the risk of coping-motivated cannabis use during a crisis.

Validation of the dimensional Yale Food Addiction Scale for Children 2.0 and estimation of the weighted food addiction score in a sample of adolescents from the general population

PURPOSE

Obesity among adolescents is becoming increasingly prevalent and "food addiction" (addiction-like attraction to foods with high content of fat and refined carbohydrates) may be a potential contributor to this development. This study aimed to investigate the psychometric properties of the dimensional Yale Food Addiction Scale for Children version 2.0 (dYFAS-C 2.0) and to estimate the weighted mean score on the dYFAS-C 2.0 (as a measure of food addiction symptom load) among adolescents from the general Danish population.

METHODS

A total of 3,750 adolescents aged 13-17 were randomly drawn from the general Danish population and invited to participate in a web-based survey. Data on health and socioeconomic factors from the Danish registers were linked to both respondents and non-respondents, which allowed for analysis of attrition. The total- and sex-stratified weighted mean dYFAS-C 2.0 scores were estimated using augmented inverse probability weighted estimation.

RESULTS

A total of n = 576 (15.4%) adolescents participated in survey of whom 55.6% were female. The confirmatory factor analysis of the dYFAS-C 2.0 supported a one-factor model. The dYFAS-C 2.0 total score was associated with eating pathology, BMI z-scores, and ADHD symptomatology. The weighted mean dYFAS-C 2.0 score was 12.1 (95% CI: 11.2;12.9), 15.0 (95% CI: 13.9;16.2) for females and 9.5 (95% CI: 8.3;10.6) for males.

CONCLUSIONS

The dYFAS-C 2.0 appears to be a psychometrically valid tool to assess symptoms of food addiction among adolescents. Food addiction symptom severity correlated positively with eating pathology (including restrained eating), BMI z-scores, and ADHD symptomatology. Level IV, observational cross-sectional descriptive study combined with retrospective register data.

The association of type of cannabis product used and frequency of use with problematic cannabis use in a sample of young adult cannabis users

Research exploring patterns and predictors of problematic cannabis use behaviors among young adults is limited. This knowledge is essential for intervening to prevent abuse and dependence outcomes.

METHODS

Young adult cannabis users (Mage = 19.2[SD = 0.8]) in Southern California (N = 1007) were classified by patterns of problematic cannabis use from the Cannabis Abuse Screening Test, using Latent Class Analysis. Multinomial regression evaluated the association of frequency of use (no past 30 day use, infrequent [use on 1-2 of past 30 days], semi-frequent [use on 3-9 of the past 30 days], and frequent [use on 10 or more of the past 30 days]) for each cannabis product type (combustible, edible, vaporized, concentrate, blunt) with class membership.

RESULTS

Four distinct classes of cannabis-related problems were identified: "non-symptomatic" (no problems; 33.8 %), "non-recreational use" (before noon and when alone; 34.5 %), "moderate use problems" (before noon, alone, and memory problems; 8.0 %), and "severe cannabis problems" (all 6 problems; 23.7 %). Semi-frequent (AOR range: 1.85-4.63;ps<0.05) and frequent (AOR range: 9.18-24.2;ps<0.05) use of combustible and vaporized cannabis, frequent blunt use (AORs range: 4.03-10.3;ps<0.05), and semi-frequent, but not frequent edible use (AOR range: 2.57-2.73;ps<0.05) was associated with higher odds of classification in any problematic use class (vs. non-symptomatic).

CONCLUSIONS

Differences in cannabis use problems across these classes and their predictors reveal the heterogeneity in cannabis-related problems experienced by young people. Combustible cannabis, vaporized cannabis, and blunt cannabis use may confer the most risk for cannabis abuse and dependency outcomes, with more frequent days of use contributing to increased patterns of risk.

A narrative review of highly processed food addiction across the lifespan

Evidence is growing that highly processed (HP) foods (i.e., foods high in refined carbohydrates and fat) are highly effective in activating reward systems and may even be capable of triggering addictive processes. Unlike traditional drugs of abuse, exposure to HP foods is common very early in development. HP food addiction has been associated with negative outcomes, including higher body mass index (BMI), more frequent binge eating, greater failure in weight loss treatment trials, and poorer mental and physical health. Although most research on HP food addiction has been conducted using adult samples, research on this topic now spans across the life span beginning in utero and extending through older adulthood. HP food addiction and related reward-based changes are associated with negative outcomes at every life stage, which has important implications for developmentally tailored prevention and treatment efforts. Using a developmentally informed approach, the current study comprehensively reviews the existing research on HP food addiction across the lifespan and highlights important areas of future research.

Gender-based differential item functioning in the Cannabis-Associated Problems Questionnaire: A replication and extension

BACKGROUND

Gender bias in measures of cannabis problems may differentially affect how men and women endorse items. This gender invariance might mask, exaggerate, or otherwise obscure true distinctions in experiences of cannabis consequences.

METHODS

The Cannabis-Associated Problems Questionnaire (CAPQ), a measure of interpersonal deficits, occupational impairment, psychological issues, and physical side effects related to cannabis use, contained items with gender-based differential item functioning (DIF) in previous work-a finding we aim to replicate and extend (Lavender, Looby, & Earleywine, 2008).

RESULTS

In a sample of 4053 cannabis users, gender differences were apparent in global scores on the CAPQ. A DIF analysis revealed two gender-biased items, including one identified previously. Removal of these items did not significantly alter the scale's relation to cannabis use. Gender differences on the CAPQ persisted after removal of the two problematic items, indicating true gender differences still exist in men and women's experiences of cannabis-related consequences. Gender appeared to significantly contribute to scores on the full CAPQ and the short-form of the CAPQ with biased item removed, even after controlling for indices of cannabis use.

CONCLUSIONS

These findings suggest that the CAPQ evidences less gender bias than previously thought, perhaps due to diminishing gender-based stereotypes. Future work might opt to use the short form of the CAPQ to minimize gender-based DIF. In addition, potential biases in measures of substance use problems deserve more attention.

Preliminary validation of the Yale Food Addiction Scale for Children 2.0: A dimensional approach to scoring

OBJECTIVE

Assessment approaches for food addiction in younger samples have not been updated to reflect recently revised diagnostic approaches for addictive disorders. The aim of the current study is to develop a new dimensional approach to assess food addiction in adolescents that is psychometrically sound, developmentally appropriate, and reflective of the updated diagnostic criteria.

METHODS

The dimensional Yale Food Addiction Scale for Children 2.0 (dYFAS-C 2.0) and related measures were administered to 127 adolescents from the community in the United States. Endorsement rates for each question were reviewed, and the psychometric properties were evaluated.

RESULTS

Problem-focused symptoms had low endorsement rates and were excluded from the final version of the scale. The dYFAS-C 2.0 demonstrated partial evidence for a one-factor structure, had good internal consistency reliability, and was positively associated with emotional eating, external eating, and body mass index (BMI). The dYFAS-C 2.0 also accounted for unique variance in BMI. Unexpectedly, the dYFAS-C 2.0 was positively associated with restrained eating.

CONCLUSIONS

The dYFAS-C 2.0 appears to have adequate psychometric properties for assessing food addiction in community samples of adolescents. Future research should evaluate the measure in clinical samples and investigate the association between food addiction and restrained eating over the lifespan.

The Cannabis Abuse Screening Test and the DSM-5 in the general population: Optimal thresholds and underlying common structure using multiple factor analysis

The Cannabis Abuse Screening Test (CAST) aims at screening the problematic use of cannabis. It has never been validated against the Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 and its relationships with this latter have never been studied. We used a probabilistic telephone survey collected in 2014 (1351 past-year cannabis users aged 15-64) implementing the CAST and a DSM-5 adaptation of the Munich Composite International Diagnostic Interview assessing cannabis use disorders. Data were weighted, and CAST items were considered categorical. Factorial structures were assessed with confirmatory factor analyses; the relationships between the instruments were studied with multiple factor analysis (MFA). One factor for the DSM-5 and two correlated factors for the CAST were the best confirmatory factor analyses solutions. The CAST thresholds for screening moderate/severe and severe cannabis use disorders were 5 (sensitivity = 78.2% and specificity = 79.6%) and 8 (sensitivity = 86.0% and specificity = 86.7%), respectively. The MFA identified two orthogonal dimensions: The first was equally shared by both instruments; the second was the second CAST dimension (extreme frequencies of use before midday and alone, memory problems, and reproaches from friends/family). The CAST structure and screening properties were confirmed. The MFA explains its screening performances by its first dimension and identified the problematic patterns (the second dimension) that are not captured by the DSM-5.

The generalizability of the structure of substance abuse and antisocial behavioral syndromes: A systematic review

BACKGROUND

Although several authors have suggested that a single externalizing spectrum encompassing both antisocial behavioral syndromes and substance use disorder is to be preferred, this assumption has not been evaluated systematically throughout studies.

PURPOSE

The objective was to establish the generalizability of transdiagnostic models of externalizing disorders across different types of disorders and populations, in regard to the strength of the evidence.

METHOD

We conducted a systematic literature review using combinations of two sets of keywords: 1) "antisocial", "externalizing", "conduct disorder", "disruptive behavior disorder", "substance abuse", "substance-related disorder", "cannabis", "cocaine", "hallucinogen", "alcoholism", "opioid"; 2) "latent structure", "factor analysis", "multivariate analysis".

RESULTS

Models supporting a superordinate factor appeared dominant in a limited set of different populations, on which the majority of the research sample was focused.

CONCLUSIONS

Although the externalizing spectrum model is a promising angle for future research and treatment, extending research on this model in a higher diversity of populations is recommended to enhance the understanding and applicability of the externalizing spectrum model.

The Cannabis Abuse Screening Test (CAST) revisited: examining measurement invariance by age

Defensible use of self-reported cannabis use problem scales in age comparative frameworks requires that measured constructs have equal psychometric properties across age groups. This study compares the psychometric properties of the Cannabis Abuse Screening Test (CAST) across three age groups (18-24, 25-29, 30-40). Data was collected online from an accessible sample of 1316 cannabis users. Factor analysis compared the optimal factor structure and dimensionality diffraction. Multi-group Model Invariance tests examined measurement invariance across the three age groups. CAST was two-dimensional in all age groups with one factor measuring cannabis use problems and the other measuring deviation from a common standard of use. The two-dimensional structure was more pronounced in older age groups. Weak factorial invariance was supported, suggesting that the meaning of the CAST factors is equivalent across age groups. Partial, but not full, strong factorial invariance was supported, indicating that only the cannabis use problem factor can be defensibly used to measure age group mean differences. Results confirm a well-defined two-dimensional CAST structure and factorial invariance across age groups. However, caution is needed when using the two items measuring deviation from a common standard in an age-comparative framework. Replication studies based on a representative sample are needed.

Predictive validity of cannabis consumption measures: Results from a national longitudinal study

BACKGROUND

Validating the utility of cannabis consumption measures for predicting later cannabis related symptomatology or progression to cannabis use disorder (CUD) is crucial for prevention and intervention work that may use consumption measures for quick screening. This study examined whether cannabis use quantity and frequency predicted CUD symptom counts, progression to onset of CUD, and persistence of CUD.

METHODS

Data from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) at Wave 1 (2001-2002) and Wave 2 (2004-2005) were used to identify three risk samples: (1) current cannabis users at Wave 1 who were at risk for having CUD symptoms at Wave 2; (2) current users without lifetime CUD who were at risk for incident CUD; and (3) current users with past-year CUD who were at risk for persistent CUD. Logistic regression and zero-inflated Poisson models were used to examine the longitudinal effect of cannabis consumption on CUD outcomes.

RESULTS

Higher frequency of cannabis use predicted lower likelihood of being symptom-free but it did not predict the severity of CUD symptomatology. Higher frequency of cannabis use also predicted higher likelihood of progression to onset of CUD and persistence of CUD. Cannabis use quantity, however, did not predict any of the developmental stages of CUD symptomatology examined in this study.

CONCLUSIONS

This study has provided a new piece of evidence to support the predictive validity of cannabis use frequency based on national longitudinal data. The result supports the common practice of including frequency items in cannabis screening tools.

Commonalities and Differences Across Substance Use Disorders: Phenomenological and Epidemiological Aspects

BACKGROUND

Although psychoactive substances vary in many ways, they have important commonalties, particularly in their ability to lead to an addiction syndrome. The field lacks an updated review of the commonalities and differences in the phenomenology of alcohol, cannabis, tobacco, stimulants, opioids, hallucinogens, sedatives/tranquilizers, and inhalants and their related substance use disorders (SUDs).

METHODS

DSM-IV and DSM-5 SUD diagnostic criteria were reviewed, as was evidence from recent epidemiological and clinical research: psychometric studies (test-retest reliability, latent trait analysis); physiological indicators (tolerance, withdrawal); prevalence and age of onset. Information was incorporated from previous reviews, PubMed and Scopus literature searches, and data from large U.S. national surveys.

RESULTS

Empirical evidence in the form of test-retest reliability and unidimensionality supports use of the same DSM-IV dependence or DSM-5 SUD diagnostic criteria across substances. For most substances, the criteria sets were generally most informative in general population samples at moderate-to-severe levels of SUD. Across substances, 2 criteria (tolerance and use in hazardous situations) were identified as functioning differently in population subgroups. Since substances have different pharmacological effects, withdrawal is assessed using substance-specific symptoms, while tolerance is not; issues remain with the assessment of tolerance. Alcohol, tobacco, and cannabis were consistently identified as the substances with earliest onset of use, highest prevalence of lifetime use, and highest prevalence of lifetime disorder.

CONCLUSIONS

Despite differences between psychoactive substances, the generic DSM criteria set appears equally applicable across substances. Additional studies of tolerance and hazardous use will be useful for future nosologies. Alcohol, cannabis, and tobacco are the substances with the greatest public health impact due to the high prevalence and early onset of their use, and the potential all 3 substances have to lead to addiction.

The prevalence of cannabis withdrawal and its influence on adolescents' treatment response and outcomes: a 12-month prospective investigation

BACKGROUND

Withdrawal, a diagnostic indicator of cannabis use disorder, is often minimized or ignored as a consequence of cannabis use, particularly among adolescents. This study aims to characterize cannabis withdrawal among adolescents in outpatient treatment for substance use disorder and evaluate the clinical significance of withdrawal as a predictor of substance-related outcomes.

METHODS

Adolescent outpatients (N = 127) reporting cannabis as their drug of choice (n = 90) were stratified by the presence of withdrawal and compared on demographic and clinical variables at treatment intake. Hierarchical linear models compared the effect of withdrawal on percentage days abstinent (PDA) and related outcomes over a 1-year follow-up period.

RESULTS

Adolescents reporting withdrawal (40%) were more likely to meet criteria for cannabis dependence, have higher levels of substance use severity, report more substance-related consequences, and have a mood disorder. Withdrawal was not associated with PDA over the follow-up period; however, this relationship was moderated by problem recognition such that adolescents reporting withdrawal and a drug problem improved at a greater rate with respect to PDA than those who did not recognize a problem with drugs and did not report withdrawal.

DISCUSSION

Withdrawal is common among adolescent outpatients and is associated with a more clinically severe profile. In this sample, all adolescents reporting withdrawal met criteria for cannabis dependence, suggesting that withdrawal is a highly specific indicator of cannabis use disorder. Although withdrawal does not seem to be independently associated with substance use outcomes posttreatment, moderating factors such as drug problem recognition should be taken into account when formulating treatment and continuing care plans.

Properties of the Cannabis Abuse Screening Test (CAST) in the general population

This paper explores the DSM-IV latent structure of cannabis users (especially its invariance towards gender and age) and assesses the psychometric properties of the Cannabis Abuse Screening Test (CAST) by confrontation with the theoretical diagnoses [dependence and cannabis use disorders (CUD)] and the latent class structure of the DSM-IV. The random sample comprised 550 French cannabis smokers aged 15-62 years interviewed by telephone. DSM-IV diagnoses were assessed with the Munich Composite International Diagnostic Interview. Internal structures of both instruments were assessed using factor analysis and latent class analysis. Optimal CAST cutoffs were determined by sensitivity, specificity and area under the receiver operating curve (AUC). CAST and DSM-IV were unidimensional (Cronbach's α = 0.742 and 0.752, respectively), although a two-factor solution showed a better fit for the CAST. CAST cutoffs for screening CUD and dependence were three (AUC = 0.851) and five (AUC = 0.868), respectively. DSM-IV latent class structure varied only marginally in age and gender. Three classes of cannabis smokers were determined, ordered along a continuum of symptoms: non-symptomatic (61.1%), moderate (32.9%) and severe (6.0%). CAST cutoff scores for screening moderate/severe and severe were, respectively, three (AUC = 0.869) and eight (AUC = 0.952). Results are compared to those obtained in previous CAST studies and discussed in line with the DSM-5.

Functioning of cannabis abuse and dependence criteria across two different countries: the United States and The Netherlands

BACKGROUND

Cross-national differences could affect the likelihood of endorsement of DSM cannabis abuse and dependence criteria. The present study examines whether cannabis abuse and dependence criteria function differently across U.S. and Dutch cannabis users.

METHOD

Data on lifetime endorsement of DSM-IV cannabis abuse/dependence criteria were utilized from U.S. cannabis users who participated in the National Epidemiological Survey on Alcohol and Related Conditions (NESARC) and from Dutch cannabis users who participated in the Zuid-Holland study. In total, 1,568 cannabis users participated in the NESARC sample, and 359 cannabis users participated in the Zuid-Holland sample. The DSM-IV cannabis abuse/dependence criteria as well as cannabis withdrawal were determined using face-to-face computer-assisted personal interviews.

RESULTS

Using Restricted Factor Analysis with Latent Moderated Structures, the cannabis abuse/dependence criteria legal problems (β = -0.43), failed quit attempts (β = -1.09), use despite problems (β = -0.32), and withdrawal (β = -0.53) showed measurement bias, and were more likely to be endorsed by U.S. than by Dutch cannabis users. Also, men were more likely than women to endorse the criteria hazardous use (β = -0.27), legal problems (β = -0.49) and tolerance (β = -0.20). Findings on failed quit attempts and withdrawal were replicated in matched subsamples, while results on legal problems (country and gender) were partly replicated.

CONCLUSIONS

Several CUD criteria showed measurement bias across two countries and between males and females. Therefore, differences between countries and gender in prevalence rates of CUD should be regarded with caution.

Latent class analysis of DSM-5 criteria for opioid use disorders: results from the Iranian National Survey on Mental Health

BACKGROUND

Assessments of DSM-IV and DSM-5 criteria with sample populations of opioid users are limited. This study aimed to determine the number of latent classes in opioid users and assessment of the proposed revisions to the DSM-5 opioid use disorder (OUD) criteria.

METHODS

Data came from the 2011 Iranian National Mental Health Survey (IranMHS) on 7,886 participants aged 15-64 years living in Iran. We used the Composite International Diagnostic Interview (CIDI) version 2.1 in all respondents who indicated using opioids at least 5 times in the previous 12 months (n = 236).

RESULTS

A three-class model provided the best fit of all the models tested. Classes showed a spectrum of severity that was compatible with the DSM-5 classification. 'Legal problems' and 'desire to cut down' showed poor discrimination between classes. The weighted prevalence of OUD using DSM-5 was 20.7% higher than with DSM-IV.

CONCLUSIONS

RESULTS support the grouping based on severity of symptoms, combining abuse and dependence into a single diagnosis, omitting legal problems, and addition of craving as a new criterion.

Effectiveness of A-CRA/ACC in treating adolescents with cannabis-use disorders

An evidence-based treatment for adolescent cannabis users, Adolescent Community Reinforcement Approach with Assertive Continuing Care, was implemented in a rural county and small city in the USA. A total of 147 adolescents, ages 12-18, were enrolled and assessed at baseline and three time points: 3, 6, and 12 months using the Global Appraisal of Individual Needs and related measures. Program effectiveness was confirmed. The treatment was equally effective for youth from the city versus the county. More than two-thirds (68.7%) of the adolescents reported quitting use of cannabis by 12 months. The days of cannabis use in the last 90 days decreased significantly from the first follow-up, controlling for age (p value < .01), and shows consistent decline until the end of the treatment. In addition to reduction in substance use, the average number of days missing school and expelled from school decreased significantly from baseline to the end of the treatment.

Psychometric properties of the Cannabis Abuse Screening Test in Hungarian samples of adolescents and young adults

AIM

The aim of our study was to analyze psychometric properties of the Cannabis Abuse Screening Test (CAST).

METHODS

Our sample comprised Hungarian high school (n = 476; male 56.3%; mean age 19.0 years, SD = 0.65 years) and college students (n = 439; male 65.1%; mean age 23.9 years, SD = 1.56 years) who reported cannabis use in the past year. The sample covered the five biggest universities of Hungary. Besides the CAST, participants responded to the Munich-Composite International Diagnostic Interview. Factor structure was analyzed by a confirmatory factor analysis. Receiver operating characteristic curve analysis was made to assess cut-off scores. Data collection took place in 2010.

RESULTS

CAST proved to be a reliable (Cronbach's α 0.71 and 0.76) one-dimensional measure. Regarding both cannabis dependence and cannabis use disorders, a cut-off of 2 points proved to be ideal in both samples, resulting in optimal specificity, negative predictive values and accuracy, but less than optimal positive predictive values (dependence) and low sensitivity (cannabis use disorder).

DISCUSSION AND CONCLUSIONS

In line with former results, the CAST proved to be an adequate measure for the screening of cannabis-related problems among adolescents and young adults in an Eastern European country where this scale has not been studied before.

DSM-5 cannabis use disorder: a phenotypic and genomic perspective

BACKGROUND

We explore the factor structure of DSM-5 cannabis use disorders, examine its prevalence across European- and African-American respondents as well as its genetic underpinnings, utilizing data from a genome-wide study of single nucleotide polymorphisms (SNPs). We also estimate the heritability of DSM-5 cannabis use disorders explained by these common SNPs.

METHODS

Data on 3053 subjects reporting a lifetime history of cannabis use were utilized. Exploratory and confirmatory factor analyses were conducted to create a factor score, which was used in a genome-wide association analysis. p-values from the single SNP analysis were examined for evidence of gene-based association. The aggregate effect of all SNPs was also estimated using Genome-Wide Complex Traits Analysis.

RESULTS

The unidimensionality of DSM-5 cannabis use disorder criteria was demonstrated. Comparing DSM-IV to DSM-5, a decrease in prevalence of cannabis use disorders was only noted in European-American respondents and was exceedingly modest. For the DSM-5 cannabis use disorders factor score, no SNP surpassed the genome-wide significance testing threshold. However, in the European-American subsample, gene-based association testing resulted in significant associations in 3 genes (C17orf58, BPTF and PPM1D) on chromosome 17q24. In aggregate, 21% of the variance in DSM-5 cannabis use disorders was explained by the genome-wide SNPs; however, this estimate was not statistically significant.

CONCLUSIONS

DSM-5 cannabis use disorder represents a unidimensional construct, the prevalence of which is only modestly elevated above the DSM-IV version. Considerably larger sample sizes will be required to identify individual SNPs associated with cannabis use disorders and unequivocally establish its polygenic underpinnings.

The choice of screening instrument matters: the case of problematic cannabis use screening in spanish population of adolescents

The aim of this study was to examine the feasibility of problem cannabis use screening instruments administration within wide school surveys, their psychometric properties, overlaps, and relationships with other variables. Students from 7 Spanish regions, aged 14–18, who attended secondary schools were sampled by two-stage cluster sampling (net sample 14,589). Standardized, anonymous questionnaire including DSM-IV cannabis abuse criteria, Cannabis Abuse Screening Test (CAST), and Severity of Dependence Scale (SDS) was self-completed with paper and pencil in the selected classrooms. Data was analysed using classical psychometric theory, bivariate tests, and multinomial logistic regression analysis. Not responding to instruments' items (10.5–12.3%) was associated with reporting less frequent cannabis use. The instruments overlapped partially, with 16.1% of positives being positive on all three. SDS was more likely to identify younger users with lower frequency of use who thought habitual cannabis use posed a considerable problem. CAST positivity was associated with frequent cannabis use and related problems. It is feasible to use short psychometric scales in wide school surveys, but one must carefully choose the screening instrument, as different instruments identify different groups of users. These may correspond to different types of problematic cannabis use; however, measurement bias seems to play a role too.

DSM-5 criteria for substance use disorders: recommendations and rationale

Since DSM-IV was published in 1994, its approach to substance use disorders has come under scrutiny. Strengths were identified (notably, reliability and validity of dependence), but concerns have also arisen. The DSM-5 Substance-Related Disorders Work Group considered these issues and recommended revisions for DSM-5. General concerns included whether to retain the division into two main disorders (dependence and abuse), whether substance use disorder criteria should be added or removed, and whether an appropriate substance use disorder severity indicator could be identified. Specific issues included possible addition of withdrawal syndromes for several substances, alignment of nicotine criteria with those for other substances, addition of biomarkers, and inclusion of nonsubstance, behavioral addictions.This article presents the major issues and evidence considered by the work group, which included literature reviews and extensive new data analyses. The work group recommendations for DSM-5 revisions included combining abuse and dependence criteria into a single substance use disorder based on consistent findings from over 200,000 study participants, dropping legal problems and adding craving as criteria, adding cannabis and caffeine withdrawal syndromes, aligning tobacco use disorder criteria with other substance use disorders, and moving gambling disorders to the chapter formerly reserved for substance-related disorders. The proposed changes overcome many problems, while further studies will be needed to address issues for which less data were available.

Reliability and validity of the Severity of Dependence Scale for detecting cannabis dependence in frequent cannabis users

The Severity of Dependence Scale (SDS) measures with five items the degree of psychological dependence on several illicit drugs, including cannabis. Its psychometric properties have not yet been examined in young adult frequent cannabis users, an eminently high-risk group for cannabis dependence. Internal consistency and criterion validity of the SDS were investigated within an enriched community based sample of 577 Dutch frequent (≥ three days per week in the past 12 months) cannabis users between 18-30 years. Criterion validity was tested against the Composite International Diagnostic Interview (CIDI) 3.0 DSM-IV diagnosis cannabis dependence, and psychometric properties were assessed separately for males and females and for ethnic subgroups. Principal component analysis showed that all items of the scale loaded on a single factor and reliability of the SDS total score was good (Cronbach's α = 0.70). However, criterion validity against the CIDI diagnosis cannabis dependence was low: area under curve (AUC) was 0.68 (95% confidence interval: 0.64-0.73) and at the optimal differentiating cut-off (SDS ≥ 4), sensitivity was 61.3% and specificity 63.5%. Results were similar for subgroups on gender and ethnicity. While internal consistency of the SDS is good, its use as a screener to differentiate between dependence and non-dependence within populations of young adult frequent cannabis users is not recommended.

Optimal scaling of the CAST and of SDS Scale in a national sample of adolescents

PURPOSE

Psychometric and screening properties of the Cannabis Abuse Screening Test (CAST) and of the Severity Dependence Scale (SDS) were investigated using DSM-IV diagnoses of cannabis dependence (CD) as external criteria. Performance of the SDS and of the CAST were compared.

METHODS

Cross-sectional European School Survey Project on Alcohol and Other Drugs (ESPAD) was carried out in Italy in 2009. The sample consisted of 5787 Italian adolescents aged 15-19 who reported cannabis last year use. Uni-dimensionality, internal reliability, external validity, and optimal scaling of the 6 items for CAST and 5 items for SDS were performed. The Munich Composite International Diagnostic Interview (M-CIDI) was used as a gold standard for DSM-IV diagnoses, and all outputs were assessed by 10-fold cross validation procedure.

RESULTS

Both scales were uni-dimensional and Cronbach's α was 0.74 for SDS and 0.78 for CAST. High and comparable area under curve (AUC) values indicate a good ability of both scales to discriminate between individuals with and without dependence diagnosis. Based on balanced sensitivity and specificity, the optimal cut-off scores for problematic use disorders were 7 for CAST MCA and 4 for SDS MCA. Both CAST and SDS overestimated CD prevalence.

CONCLUSIONS

The CAST and SDS are equally useful for screening for problematic cannabis use disorders. Both clinical and research applications of the scales are possible.

A validation of the Cannabis Abuse Screening Test (CAST) using a latent class analysis of the DSM-IV among adolescents

This paper explored the latent class structure of the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) (assessed with the Munich Composite International Diagnostic Interview). Secondly, the screening properties of the Cannabis Abuse Screening Test (CAST) in adolescents were assessed with classical test theory using the latent class structure as empirical gold standard. The sample comprised 3266 French cannabis users aged 17 to 19 from the general population. Three latent classes of cannabis users were identified reflecting a continuum of problem severity: non-symptomatic, moderate and severe. Gender-specific analyses showed the best model fit, although results were almost identical in the total sample. The latent classes were good predictors of daily cannabis use, number of joints per day and age of first experimentation. The CAST showed good screening properties for the moderate/severe class (area under receiver operating characteristic curve > 0.85) and very good for the severe class (0.90). It was more sensitive for boys, more specific for girls. Although structural equivalence across gender was rejected, results suggest small gender differences in the latent structure of the DSM-IV. The performance of the CAST in screening for the latent class structure was good and superior to those obtained with the classical DSM-IV diagnoses.

Contributions of ethnicity to differential item functioning of cannabis abuse and dependence symptoms

OBJECTIVE

Cannabis is the most widely used illicit drug in the United States, and as a result, it is associated with significant public health costs. The present study sought to investigate whether item response theory (IRT) methods could be used to identify meaningful differences in how cannabis abuse and dependence symptoms (determined by criteria from the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) function as indices of the severity of misuse across two ethnic groups: Native Americans and European Americans.

METHOD

Participants were drawn from two previously collected samples, a population of Native Americans living on contiguous reservations (n = 406) and the University of California at San Francisco Family Alcoholism Study (n = 728). Cannabis use disorder symptoms were assessed using the Semi-Structured Assessment for the Genetics of Alcoholism.

RESULTS

Exploratory factor analysis demonstrated that the cannabis abuse and dependence symptoms indexed a single latent trait measuring severity of cannabis use. IRT and multiple indicators multiple causes (MIMIC) analyses suggested meaningful differences in the functioning of these symptoms across ethnic groups. Withdrawal represented a more prevalent and less severe symptom among Native Americans relative to European Americans, whereas each of the cannabis abuse symptoms and a symptom assessing psychological and health problems resulting from cannabis use were less prevalent but more severe in Native Americans.

CONCLUSIONS

The findings suggest differences in how cannabis use disorders manifest in these populations and thus have implications for the assessment of these disorders as well as theories attempting to explain the increased rates of substance use diagnoses more generally among Native Americans living on reservations.

Quantifying the clinical significance of cannabis withdrawal

Background and Aims

Questions over the clinical significance of cannabis withdrawal have hindered its inclusion as a discrete cannabis induced psychiatric condition in the Diagnostic and Statistical Manual of Mental Disorders (DSM IV). This study aims to quantify functional impairment to normal daily activities from cannabis withdrawal, and looks at the factors predicting functional impairment. In addition the study tests the influence of functional impairment from cannabis withdrawal on cannabis use during and after an abstinence attempt.

Methods and Results

A volunteer sample of 49 non-treatment seeking cannabis users who met DSM-IV criteria for dependence provided daily withdrawal-related functional impairment scores during a one-week baseline phase and two weeks of monitored abstinence from cannabis with a one month follow up. Functional impairment from withdrawal symptoms was strongly associated with symptom severity (p = 0.0001). Participants with more severe cannabis dependence before the abstinence attempt reported greater functional impairment from cannabis withdrawal (p = 0.03). Relapse to cannabis use during the abstinence period was associated with greater functional impairment from a subset of withdrawal symptoms in high dependence users. Higher levels of functional impairment during the abstinence attempt predicted higher levels of cannabis use at one month follow up (p = 0.001).

Conclusions

Cannabis withdrawal is clinically significant because it is associated with functional impairment to normal daily activities, as well as relapse to cannabis use. Sample size in the relapse group was small and the use of a non-treatment seeking population requires findings to be replicated in clinical samples. Tailoring treatments to target withdrawal symptoms contributing to functional impairment during a quit attempt may improve treatment outcomes.

A dimensional approach to understanding severity estimates and risk correlates of marijuana abuse and dependence in adults

While item response theory (IRT) research shows a latent severity trait underlying response patterns of substance abuse and dependence symptoms, little is known about IRT-based severity estimates in relation to clinically relevant measures. In response to increased prevalences of marijuana-related treatment admissions, an elevated level of marijuana potency, and the debate on medical marijuana use, we applied dimensional approaches to understand IRT-based severity estimates for marijuana use disorders (MUDs) and their correlates while simultaneously considering gender- and race/ethnicity-related differential item functioning (DIF). Using adult data from the 2008 National Survey on Drug Use and Health (N = 37,897), Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria for MUDs among past-year marijuana users were examined by IRT, logistic regression, and multiple indicators-multiple causes (MIMIC) approaches. Among 6917 marijuana users, 15% met criteria for a MUD; another 24% exhibited subthreshold dependence. Abuse criteria were highly correlated with dependence criteria (correlation = 0.90), indicating unidimensionality; item information curves revealed redundancy in multiple criteria. MIMIC analyses showed that MUD criteria were positively associated with weekly marijuana use, early marijuana use, other substance use disorders, substance abuse treatment, and serious psychological distress. African Americans and Hispanics showed higher levels of MUDs than Whites, even after adjusting for race/ethnicity-related DIF. The redundancy in multiple criteria suggests an opportunity to improve efficiency in measuring symptom-level manifestations by removing low-informative criteria. Elevated rates of MUDs among African Americans and Hispanics require research to elucidate risk factors and improve assessments of MUDs for different racial/ethnic groups.

Psychometric properties of the CAST and SDS scales in young adult cannabis users

AIM

To assess the validity of two cannabis use severity scales among young cannabis users and to evaluate their ability to detect Substance Use Disorders (SUD).

PARTICIPANTS

241 volunteers (18-25 years), with a wide spectrum of cannabis use in the last 12 months.

MEASUREMENTS

The Cannabis Abuse Screening Test (CAST) and Severity of Dependence Scale (SDS) were self-administered. The Psychiatric Interview for Substance and Mental Disorders (PRISM) was used as gold standard for cannabis use disorders according to DSM-IV. Reliability and validity were assessed for two different CAST coding algorithms (b-binary and f-full) and for the SDS. In addition, the cannabis use diagnostic criteria contained in the PRISM were grouped to approximate forthcoming proposed DSM-V criteria to further evaluate these scales.

FINDINGS

26.6% (95% CI: 21.0-32.2) of the subjects met criteria for cannabis dependence, and 49.0% (95% CI: 42.7-55.3) for cannabis use disorders. For both scales internal consistency (Cronbach's alpha>0.71) and test-retest intraclass correlation coefficients (>0.80) were good. The score 12 in the CAST-full discriminated better than others between presence and absence of dependence (27.0%; 95% CI: 21.4-32.6) while the score for discrimination of SUD was 9 (51.5%; 95% CI: 45.1-57.8). For the SDS the values were 7 (22.0%; 95% CI: 16.8-27.2) and 3 (64.7%; 95% CI: 58.7-70.8), respectively. According to proposed DSM-V criteria, for moderate and severe addiction the values for the CAST-f were 7 (68.5%; 95% CI: 62.5-74.3) and 12 (27%; 95% CI: 21.3-32.6) and for the SDS, 3 (65.0%; 95% CI: 58.7-70.8) and 7 (22%; 95% CI: 17.0-34.3), respectively.

CONCLUSIONS

The CAST and SDS applied to young cannabis users are reliable and valid measures to detect cannabis use disorders when compared to both DSM-IV and proposed DSM-V criteria.

Analyses related to the development of DSM-5 criteria for substance use related disorders: 2. Proposed DSM-5 criteria for alcohol, cannabis, cocaine and heroin disorders in 663 substance abuse patients

BACKGROUND

A number of changes have been proposed and investigated in the criteria for substance use disorders in DSM-5. However, although clinical utility of DSM-5 is a high priority, relatively little of the empirical evidence supporting the changes was obtained from samples of substance abuse patients.

METHODS

Proposed changes were examined in 663 patients in treatment for substance use disorders, evaluated by experienced clinicians using the Psychiatric Research Interview for Substance and Mental Disorders (PRISM). Factor and item response theory analysis was used to investigate the dimensionality and psychometric properties of alcohol, cannabis, cocaine and heroin abuse and dependence criteria, and craving.

RESULTS

The seven dependence criteria, three of the abuse criteria (hazardous use; social/interpersonal problems related to use; neglect of roles to use), and craving form a unidimensional latent trait for alcohol, cannabis, cocaine and heroin. Craving did not add significantly to the total information offered by the dependence criteria, but adding the three abuse criteria and craving together did significantly increase total information for the criteria sets associated with alcohol, cannabis and heroin.

CONCLUSION

Among adult patients in treatment for substance disorders, the alcohol, cannabis, cocaine and heroin criteria for dependence, abuse (with the exception of legal problems), and craving measure a single underlying dimension. Results support the proposal to combine abuse and dependence into a single diagnosis in the DSM-5, omitting legal problems. Mixed support was provided for the addition of craving as a new criterion, warranting future studies of this important construct in substance use disorders.