Replicating the Dimensional Structure of Cannabis Problems: A Taxometric Analysis.

OBJECTIVE: This study employed taxometric procedures to replicate a previous report of the dimensional structure of problems related to cannabis consumption. Method: Over 4,000 cannabis users completed an assessment of psychological, social, occupational, and physical harms (the Marijuana Problems Scale). Three taxometric procedures (MAMBAC, MAXEIG, and L-Mode) compared the current data to simulations with a base rate of problematic cannabis use derived from representative, large-scale data estimates. Results: All three procedures confirmed the continuous, dimensional nature of these cannabis problems and suggested no underlying taxon or category. Conclusions: Psychopathological disorders, including some substance use problems, have fit categorical models suggesting that they differ in kind (rather than intensity) from the behavior of the rest of the population. Cannabis problems, however, appeared to lie along a continuum with other forms of use. Given heightened awareness for the necessity of replication and a changing legal landscape for cannabis, a second look at the dimensionality of these problems seemed warranted. New data with a larger sample and different indices of problematic use confirmed the dimensionality of cannabis problems. This replication can inform predictions about the etiology, prevention, and treatment of cannabis use disorder. Researchers should expect cannabis problems to range along a continuum without categorical distinctions. Dividing users into groups of problematic and non-problematic users likely sacrifices meaningful variance. Harm reduction strategies likely can benefit all users rather than a targeted taxon with troubles. In addition, interventions will likely progress by small, incremental steps rather than dramatic, categorical jumps in progress.

Savoring Moderates the Link between Marijuana Use and Marijuana Problems.

Background: The changing legal landscape for marijuana requires concerted efforts toward minimizing the potential harms related to use of the plant. Purpose/Objectives: Identifying buffers against negative consequences in regular users could help researchers fashion prevention efforts that could appeal to those who are uninterested in messages related to abstinence. Savoring, a positively-focused, mindful approach to making the most of positive experiences, appears to overlap with facets of treatment that have proven successful with problem users. The present study examined the role of savoring in the development of marijuana-related problems. Methods: We examined the potential role of savoring as a buffer against marijuana problems in 195 participants (27.3% female). Results: Participants in this sample used cannabis 3.06 days per week on average. Correlations revealed that problems decreased as savoring increased. In addition, a significant interaction revealed that savoring moderated the impact of frequent use on problems. As savoring increased, the positive association between frequency of use and negative consequences decreased, suggesting that those who are high on savoring experience fewer negative consequences than those who are low on savoring even when they use marijuana as frequently. Conclusions: These data support the idea of incorporating savoring into the prevention of marijuana problems.

Effects of Messaging and Psychological Reactance on Marijuana Craving.

Background: Psychological Reactance Theory asserts that people experience reactance (a motivational state characterized by negative affect and cognition) when they perceive threats to their autonomy. Reactance may lead to "boomerang effects" by which individuals engage in the opposed behavior. Objectives: This experiment sought to determine whether a message encouraging marijuana (MJ) abstinence evoked greater reactance than a harm-reduction message and whether the message and reactance influenced individuals' attitudes, MJ craving, and intent to comply with the message request. Methods: College students and community members (n = 388) participated in an online study where they were randomly assigned to receive a message promoting MJ abstinence or harm reduction. Regression analyses adjusting for MJ use, alcohol use, and age determined the effects of the message and reactance on individuals' attitudes, MJ craving, and intent to comply. Follow-up analyses determined the significant reactance subscales. Results: The abstinence message evoked greater reactance than the harm reduction message and led to less favorable attitudes toward the advocated behavior. Across messages, reactance (specifically negative cognitive appraisal) was related to less favorable attitudes toward the advocated behavior and the study, as well as lower intent to comply. Additionally, reactance (specifically anger) was associated with greater self-reported craving. Conclusions/Importance: Anti-MJ messages designed to discourage use might heighten reactance and inadvertently lead to greater craving and intent to use. The link between reactance and craving may be more affectively mediated than the link between reactance and message rejection.

Determining Cannabis Use Status From a Photograph: An Assessment of the "Jay-dar" in Neuropsychologists.

BACKGROUND: Few studies examining the cognitive effects of chronic cannabis use utilize research designs where examiners are blind to user status. Even in those that do, researchers may be able to guess the user status of participants, leaving these studies vulnerable to the expectancy effect confound. OBJECTIVES: The present study examined the ability of neuropsychologists (those who would conduct research on the cognitive effects of cannabis) to differentiate cannabis users and nonusers based on physical appearance from photographs. METHOD: We recruited 84 participants from an international neuropsychology listserv. The sample was 59.5% female and 95.2% Caucasian, with a mean age of 41.39 years (range 26-65). Each neuropsychologist rated 25 target faces (12 cannabis users, 13 nonusers) on a Marijuana Use Likelihood Index based upon individuals' photographs. RESULTS: Results indicate a main effect of user group, as neuropsychologists ascribed higher ratings to cannabis users on the Marijuana Use Likelihood Index, suggesting they perceive them as more likely to be users, relative to nonusers. Results also demonstrated a main effect of gender, as males received higher user ratings than females, and a significant main effect of rater gender, as female raters were more likely to rate individuals as cannabis users relative to male raters. Conclusions/Importance: The results demonstrate the importance of assessing researchers' expectations when studying the effects of chronic cannabis use, as even those designs that keep examiners blind to participant user status may be vulnerable to expectancy effects if examiners are able to guess user status based upon appearance alone.

Subtypes of attention deficit-hyperactivity disorder (ADHD) and cannabis use.

The current study examined the association between subtypes of attention-deficit/hyperactivity disorder (ADHD) and cannabis use within a sample of 2811 current users. Data were collected in 2012 from a national U.S. survey of cannabis users. A series of logistic regression equations and chi-squares were assessed for proportional differences between users. When asked about the ADHD symptoms they have experienced when not using cannabis, a higher proportion of daily users met symptom criteria for an ADHD diagnoses of the subtypes that include hyperactive-impulsive symptoms than the inattentive subtype. For nondaily users, the proportions of users meeting symptom criteria did not differ by subtype. These results have implications for identifying which individuals with ADHD might be more likely to self-medicate using cannabis. Furthermore, these findings indirectly support research linking relevant cannabinoid receptors to regulatory control.

Marijuana, expectancies, and post-traumatic stress symptoms: a preliminary investigation.

Previous work suggests that people might turn to marijuana to alleviate the symptoms of post-traumatic stress disorder (PTSD) and associated distress. Expectancy theories emphasize that the use of drugs correlates with their anticipated effects. The current study examined multivariate links among marijuana use, PTSD symptoms, and expectancies for marijuana-induced changes in those symptoms. Over 650 combat-exposed, male veterans who used marijuana at least once per week completed measures of PTSD symptoms, marijuana expectancies, and marijuana use in an Internet survey. Participants generally expected marijuana to relieve PTSD symptoms, especially those related to intrusions and arousal. Symptoms, expectancies for relief of symptoms, and marijuana consumption correlated significantly. Regressions revealed significant indirect effects of symptoms on use via expectancies, but no significant interactions of expectancies and symptoms. Combat-exposed veterans who use marijuana appear to use more as the magnitude of PTSD symptoms and their expectations of marijuana-induced relief of those symptoms increase. These results emphasize the importance of PTSD treatments in an effort to keep potential negative effects of marijuana to a minimum. They also underscore the import of expectancies in predicting marijuana use.

Educational Materials and Image Induction Increase Treatment Credibility.

Patient-perceived treatment credibility is linked to important outcome measures including symptom reduction, therapeutic alliance, patient satisfaction, and attrition rates. However, few studies have tested strategies to enhance treatment credibility. The present study investigates the effect of brief, written educational materials and the use of an image induction prime on perceptions of credibility for cognitive behavioral therapy and psilocybin-assisted therapy for depression. Participants (N = 493) rated the perceived credibility of depression treatments before and after reading brief educational materials. Half of the participants were asked an image induction question containing the construct of open-mindedness. Results indicate that brief educational materials of about 300 words significantly increased perceived treatment credibility for both therapies, with a large effect size (Cohen's d = .91). The use of an image induction prime further increased perceived credibility for psilocybin-assisted therapy for depression (Cohen's d = .38). These strategies offer an efficient and cost-effective way to enhance treatment credibility. Future studies testing variations of the image induction prime might prove fruitful for optimizing the technique.

Inhaled Dimethyltryptamine (DMT): Use Patterns and Predictors of Consumption Frequency.

Despite increasing interest in psychedelics and their potential therapeutic effects, research on inhaled N,N-Dimethyltryptamine (DMT) remains limited. Inhaled DMT has a reputation for rapid, dramatic onset and a brief duration, but correlates of use frequency remain poorly understood. A sample recruited from relevant internet sites, including nearly 400 people who had inhaled DMT, reported substance use histories, motivations for use, DMT sources, risk perceptions, and other variables. Generally, participants reported initiation motivated by curiosity about DMT's effects, interest in psychedelics more broadly, and potential spiritual benefits. Those who had used other psychoactive substances (especially ayahuasca) and who had extracted DMT themselves reported inhaled DMT more frequently. Most (>60%) reported obtaining DMT from a friend and claimed it was "slightly difficult" to procure. Participants most commonly inhaled DMT from a glass pipe, in private homes, frequently alone or in small groups. Salient positives associated with inhaling DMT included psychologically cleansing or cathartic experiences. Associated challenges concerned difficult integration, aversive experiences, or "bad trips." Participants rated DMT as very or slightly safe. These data underscore the need for continued work on this topic to inform education and harm reduction efforts, particularly as the molecule's reputation for ameliorative effects receives media coverage.

Rapid and sustained reduction of treatment-resistant PTSD symptoms after intravenous ketamine in a real-world, psychedelic paradigm.

BACKGROUND: Traditional treatments for post-traumatic stress disorder (PTSD) often show limited success with high dropout. Ketamine, an N-methyl-D-aspartate antagonist known for rapid antidepressant effects, has decreased PTSD symptoms in some studies but not in others. Administering ketamine in ways that parallel psychedelic-assisted treatments-including preparatory, integration, sensory immersion, and psychotherapy sessions-could decrease PTSD symptoms meaningfully. METHODS: A retrospective sample of 117 screened outpatients with elevated PTSD Checklist for DSM-5 (PCL-5) scores received intravenous ketamine in supportive environments. The protocol included preparation, intention-setting, and integration sessions accompanying at least six administrations. Administration sessions included eye shades and evocative music paralleling typical psychedelic therapy trials. RESULTS: Mean PCL scores decreased from 52.54 (SD = 12.01) to 28.78 (SD = 16.61), d = 1.64. Patients tolerated treatment well, with no serious adverse events. Covariates, including age, gender, days between PCL assessments, number of psychiatric medications, and suicidal ideation were not significant moderators; concomitant psychotherapy did reach significance, d = 0.51. Of the 117 patients' final PCL scores, 88 (75.21%) measures suggested clinically meaningful improvement and 72 (61.54%) suggested remission of PTSD symptoms. CONCLUSION: Intravenous ketamine in supportive environments, with hallmarks of psychedelic therapy, preceded large reductions in PTSD symptoms. These results highlight ketamine's potential when delivered in this manner, suggesting environmental factors might account for some variation seen in previous work. Given the molecule's cost, minimal interaction with other psychiatric medications, and legal status, intravenous ketamine in a psychedelic paradigm may be a promising option for PTSD unresponsive to other treatments.

Development of the Protective Strategies for Psychedelics Scale: A novel inventory to assess safety strategies in the context of psychedelics.

BACKGROUND: Individuals who use psychedelics take efforts to mitigate unintended consequences. Despite the demonstrated utility of analogous protective behavioral strategies (PBS) assessments for other substances, no standardized scale exists to capture these protective strategies for psychedelic use. OBJECTIVE: The present study addresses a notable gap concerning the assessment of psychedelic use, specifically by developing a scale measuring the protective strategies employed around use, called the Protective Strategies for Psychedelics Scale (PSPS). METHODS: A sample (Mage = 36.85 years old, standard deviation = 10.3; male = 61.9%; White = 85.2%) of 434 adults with lifetime use of psychedelics reported on initial qualitatively developed items for the PSPS, PBS scales for cannabis and alcohol, and use of alcohol, cannabis, and psychedelics. RESULTS: Iterative principal components analyses began with 37 items and yielded a 32-item two-factor solution demonstrating excellent internal reliability (Cronbach's α = .95) and accounted for 51.3% of the variance. Nineteen items loaded on PSPS factor 1, which focused on long-term preparation, emphasizing strategies focused on mood/intentions, preparing the substance, environment, and scheduling episode of use; 13 items loaded on factor 2, which focused on short-term preparation, highlighting strategies surrounding social context, health, and other substances. The PSPS demonstrated convergent validity with validated PBS scales for cannabis and alcohol (r = 0.71-0.79, p < 0.001), and was moderately associated with lifetime psychedelic use (r = 0.28, p < 0.001). CONCLUSION: The PSPS demonstrates promising psychometric properties, and future work validating the scale for diverse samples across research and clinical settings is warranted.

Acute Psychedelic Reactions, Post-Acute Changes in Dysfunctional Attitudes, and Psychedelic-Associated Changes in Wellbeing.

Dysfunctional attitudes - a cornerstone to cognitive psychotherapy - vary with both psychological and pharmacological interventions. Post-acute changes in these cognitions appear to covary with the acute reactions to psychedelics that often precede improved outcomes. An examination of post-acute changes in dysfunctional attitudes could support targeting them in psychedelic-assisted therapy. Screened participants (N = 400+) reported the acute, subjective experiences associated with their most significant psychedelic response as well as post-acute changes in dysfunctional attitudes and subsequent alterations in wellbeing. Dysfunctional attitudes, emotional breakthroughs, and challenging experiences accounted for significant, unique variance in wellbeing. The effects of dysfunctional attitudes generally exceeded those of acute reactions. Comparisons among those acute responses revealed that the effect of emotional breakthroughs exceeded challenging experiences, which exceeded mystical experiences. Nevertheless, the indirect effects through post-acute changes in dysfunctional attitudes did not account for all the impact of acute effects nor interact with them. These results emphasize the import of both acute and post-acute reactions, suggesting that strategies for optimizing each might maximize outcomes for psychedelic-assisted interventions. Furthermore, standard cognitive interventions that alter these cognitions could combine with psychedelics in straightforward ways. The results also support the use of multiple multivariate approaches to address the relative importance of multicollinear predictors.

Using the unmatched count technique to improve base rate estimates of risky driving behaviours among veterans of the wars in Iraq and Afghanistan.

BACKGROUND: Few studies have investigated base rate estimates of risky driving behaviours among veterans of the wars in Afghanistan and Iraq despite evidence suggesting such behaviours result in increased death rates. In addition, published estimates of driving behaviours may be subject to a significant response bias via the impact of perceived mental health stigma on honest self-reporting. AIM: The present study compared the unmatched count technique, a form of randomised response technique used to mitigate biased responding, with traditional anonymous self-report to gain information about base rates of risky driving behaviours among combat veterans. METHODS: Cross-sectional data gathered as part of a study of attitudes and behaviours related to military service provided estimates of target activities. Six facets of risky driving (horn honking, carrying firearms in the vehicle, drinking and driving, screaming at other drivers, following other drivers to complain, and tailgating) were assessed. RESULTS: In our sample of 1351 combat veterans, the unmatched count technique revealed significantly higher rates relative to traditional anonymous assessment specifically for horn honking in anger (22.1% vs 13.6%), carrying firearms (51.1% vs 32.2%), and drinking and driving (77.8% vs 54.0%). There were no significant differences for the remaining three items. CONCLUSIONS: The high level of morbidity associated with risky driving and motor vehicle crashes is a significant concern in the combat veteran population. These data suggest the presence of a strong response bias associated with endorsing certain risky driving behaviours, potentially leading to serious underestimation of these problem behaviours in standard anonymous questionnaires.

Psychedelic Experiences After Bereavement Improve Symptoms of Grief: The Influence of Emotional Breakthroughs and Challenging Experiences.

Grief, a common reaction to loss, can frequently become problematic or impairing. Available treatments for prolonged grief disorder are promising but leave room for considerable improvement. Qualitative accounts of psychedelic experiences after bereavement reveal themes that parallel core components of prolonged grief disorder therapy. However, few studies have investigated the therapeutic potential of psychedelics for symptoms of grief. The present study surveyed recreational psychedelic users (N = 363) who had suffered a bereavement event. They reported retrospective grief symptoms before and after the psychedelic experience as well as subjective reactions to the psychedelic, including emotional breakthroughs and challenging experiences. Results indicate improvements in grief symptoms after a psychedelic experience, with a large effect size (Cohen's d = 0.83). The occurrence of emotional breakthroughs was positively associated with improvements in symptoms of grief, while the converse relation was observed for challenging experiences. Findings provide preliminary evidence that support the development of a psychedelic-assisted therapy protocol to target symptoms of grief. Psychedelic-assisted therapy might offer an alternative to current grief treatment options.

Induced negative affect's impact on self-reported cannabis use, expectancies, and problems.

Substance use disorders and affective disturbances often covary. Even momentary experiences of negative affect (NA) appear linked with substance use. While strong evidence of these relations exists, NA might bias endorsements of substance use due to hindered recall and reporting processes. This hypothesis warrants further research, as accurate assessment of substance-related variables is crucial in both research and treatment settings. The present study examined the influence of NA on reporting of cannabis variables using an affect-induction paradigm. Over 700 individuals recruited from Amazon's MTurk participated. After reporting demographics and baseline affect, participants were randomly assigned to either a NA induction or control condition. Follow-up measures assessed post-induction affect and cannabis-related variables. Results revealed that the NA induction task significantly increased NA and decreased positive affect relative to the control condition. Participants assigned to the NA induction reported greater negative cannabis expectancies and more cannabis problems, even after controlling for age and educational attainment. Cannabis use and cannabis problems appeared positively related. Future research should continue to assess for the influence of NA in reporting of cannabis variables. Should subsequent work find differences in reporting of substance use that appear to covary with negative affect, clinicians and researchers alike should be mindful of the implications of potentially biased reporting on assessment, intervention, and research outcomes.

Undergraduate student perceptions of cognitive behavioral therapy, aerobic exercise, and their combination for depression.

OBJECTIVE: Both aerobic exercise and Cognitive Behavioral Therapy (CBT) improve depression, but perceptions of their credibility and efficacy are underexplored. These perceptions can contribute to treatment seeking and outcome. A previous online sample ranging in age and education rated a combined treatment higher than individual components and underestimated their efficacy. The current study is a replication exclusively focused on college students. PARTICIPANTS: Undergraduates (N = 260) participated during the 2021-2022 school year. METHODS: Students reported impressions of each treatment's credibility, efficacy, difficulty, and recovery rate. RESULTS: Students viewed combined therapy as potentially better, but also more difficult, and underestimated recovery rates, replicating previous work. Their efficacy ratings significantly underestimated both meta-analytic estimates and the previous sample's perceptions. CONCLUSIONS: Consistent underestimation of treatment effectiveness suggests that realistic education could prove especially beneficial. Students might be more willing than the broader population to accept exercise as a treatment or adjunct for depression.

How Important Is a Guide Who Has Taken Psilocybin in Psilocybin-Assisted Therapy for Depression?

Promising outcomes of Psilocybin-Assisted Therapy (PAT) for depression have generated concerted efforts to replicate, extend, and refine protocols to maximize efficacy. Psychotherapy research reveals that clients benefit most when important components of treatment align with their personal preferences. One open question related to PAT concerns the importance of the psilocybin experience of the guides (trained professionals present during acute effects). We sought to assess the importance of a guide who had used psilocybin to potential clients with depressive symptoms. Over 800 MTurk respondents with depressive symptoms rated the import of a guide who had used psilocybin relative to alternative characteristics in guides and cognitive behavioral (CBT) therapists. Importance ratings for guides who had used psilocybin significantly exceeded the "somewhat important" level (50 on a 0-100 scale), other guide-related qualities, and comparable ratings for a cognitive behavioral therapist who shared demographics, had experience with depression and received cognitive therapy personally. People of color (those who are not Caucasian) and those who had previous therapy gave significantly higher importance ratings for guides who had used psilocybin. Participants who chose to list other qualities important for guides listed very similar ones for CBT therapists, often emphasizing proper training and an empathic demeanor. Guides who have used psilocybin, who inform clients of the fact, might have advantages for facilitating PAT's antidepressant effects, as least in a subset of clients.

Scoping Review of Experiential Measures from Psychedelic Research and Clinical Trials.

Subjective responses to psychoactive drugs have served as intriguing windows into consciousness as well as useful predictors. Subjective reactions to psychedelic molecules are particularly interesting given how they covary with subsequent improvements associated with psychedelic-assisted treatments. Although links between subjective reactions and decreases in treatment-resistant clinical depression, end-of-life anxiety, and maladaptive consumption of alcohol and nicotine appear in the empirical literature, the measurement of these subjective responses has proven difficult. Several scales developed over many decades show reasonable internal consistency. Studies suggest that many have a replicable factor structure and other good psychometric properties, but samples are often small and self-selected. We review the psychometric properties of some of the most widely used scales and detail their links to improvement in response to psychedelic-assisted treatments. Generally, assessments of mystical experiences or oceanic boundlessness correlate with improvements. Challenging subjective experiences, psychological insight, and emotional breakthroughs also show considerable promise, though replication would strengthen conclusions. We suggest a collaborative approach where investigators can focus on key responses to ensure that the field will eventually have data from many participants who report their subjective reactions to psychedelic molecules in a therapeutic setting. This may aid in predicting improvement amongst targeted conditions and wellbeing.

Exploring the Credibility of Psilocybin-assisted Therapy and Cognitive-behavioral Therapy for Depression.

Depression treatments succeed with many but leave others unimproved, and they can generate concerns about side effects, time, and cost. Psilocybin has generated media attention and empirical support for antidepressant effects, but lay impressions of its effectiveness are unclear. Although perceptions of treatment credibility contribute to outcome, beliefs about the credibility of psilocybin-assisted therapy (PAT) among potential patients remain uninvestigated, especially relative to cognitive-behavioral therapy (CBT), a common, empirically-validated approach. The present study examined credibility ratings for CBT and PAT among individuals reporting depressive symptoms. Participants (N = 803) from Amazon's MTurk platform reported demographics, depressive symptoms, and psychotherapy experience, then read data-based vignettes describing each therapy and rated their credibility. Individuals rated CBT as more credible than PAT. Those with therapy experience rated CBT as more credible than those without. Men and lifetime hallucinogen users rated PAT more credible than women and non-users, but few other predictors accounted for much variance in credibility. Results suggest that potential clients appear cautious about PAT. As continued work examines the effectiveness of psychedelic-assisted interventions, researchers and clinicians must consider patients' beliefs about treatments as potential predictors of outcomes. Additionally, the paradigm used here might have potential for examining credibility of many interventions.

Cognitive Behavioral Therapy, Ketamine, and Combination Treatment for Depression: Impressions of Credibility in Participants with Self-Reported Depressive Symptoms.

Ketamine, a novel treatment for depression, has generated considerable interest and research. Few experiments address lay impressions of the credibility of ketamine treatment relative to another popular intervention for depression, CBT. Over 500 participants with depressive symptoms read descriptions of CBT, ketamine, and a treatment that combined the two. Descriptions included pros and cons of each approach. Participants found the combination treatment more credible than ketamine but no better than CBT alone. They rated the credibility of CBT alone significantly higher than ketamine alone. Participants with psychotherapy experience tended to view ketamine as less credible than those who did not report previous psychotherapy. Depression scores did not covary with credibility ratings for any treatment. Despite media coverage and Internet claims, potential clients are cautious about ketamine. These results suggest that providing descriptions of treatments might help reveal important information about their credibility to potential clients. Extended work assessing impressions of many approaches to the treatment of psychopathology and other problems appears justifiable. Given established links between credibility and treatment outcome, additional research on individual differences in perceptions of ketamine and varied treatments for depression seems warranted.

Cannabis's Link to Schizotypy: Phenomenon, Measurement Bias, or Delusion?

Links between cannabis use and psychosis generate research and media attention. Cannabis users have outscored non-users on the Schizotypal Personality Questionnaire-Brief (SPQ-B) in multiple studies, but previous work suggests that groups do not differ if biased items are removed. The present study examined links between schizotypal personality and cannabis use in a large sample recruited from Amazon's MTurk platform (N = 705). Over 500 participants reported lifetime cannabis exposure. Of those, 259 participants reported current cannabis use, and on average, used 4.53 days per week. Users and non-users failed to differ significantly on total SPQ-B scores or any of the three established subscales. The null results inspired a re-examination of the SPQ-B's factor structure, which identified a novel 3-factor solution (difficulty opening up to others, hyperawareness, and odd or unusual behavior). Only the "odd or unusual behavior" factor showed cannabis-related differences, but a differential item functioning test revealed that one subscale item showed potential bias against users. Removing this item diminished group differences. These results suggest that links between schizotypy and cannabis use require cautious interpretation with careful attention to potential measurement bias. In addition, the SPQ-B might have an alternative factor structure that could help answer important questions in psychopathology.