Examining the predictive utility of behavioral economic demand indices and subjective effects on the actualized reinforcing value of menthol cigarettes and potential alternatives.

INTRODUCTION: Considering recent and proposed bans on menthol cigarettes, methods are needed to understand the substitutability of potential menthol cigarette alternatives (MCAs) for menthol cigarettes. This study examined the prospective relationship between behavioral economic demand indices and subjective effects of usual brand menthol cigarettes (UBMC) and preferred MCAs with subsequent performance on a laboratory-based concurrent-choice task comparing UBMC and MCAs. METHODS: Eighty participants who typically smoked menthol cigarettes completed this clinical lab study. After sampling each product, participants completed the cigarette purchase task (CPT) and modified cigarette evaluation questionnaire (mCEQ). Following one-week of substituting their preferred MCA for their UBMC, participants completed a 90-min concurrent-choice self-administration task comparing their UBMC and preferred MCA. Linear regression models explored associations between CPT demand indices and mCEQ subjective effects in the lab with subsequent response effort for UBMCs on the concurrent-choice task. RESULTS: Three demand indices for UBMC were positively associated with UBMC response effort: Essential Value (EV; p=.02), Omax (p=.02), and breakpoint (p=.04). Four CPT demand indices for the preferred MCA significantly corresponded with UBMC response effort: EV (p=.03), Pmax (p=.04), Omax (p=.03), and breakpoint (p=.03). Subjective effects captured by the mCEQ were not associated with response effort. CONCLUSIONS: Demand indices reflecting Persistence (i.e., sensitivity to escalating price) predicted effort to obtain UBMC puffs on the concurrent-choice task. Among this sample, the CPT captured information on the relative reinforcing value (i.e., addiction potential) of combustible tobacco products similar to the longer self-administration task. IMPLICATIONS: In an ever-changing product market, assessing the reinforcing efficacy of menthol cigarettes and putative substitutes quickly and with validity is an important methodological tool for understanding abuse liability. Results suggest that behavioral economic demand indices of cigarette purchase task efficiently capture information on the relative reinforcing value of usual brand menthol cigarettes and plausible alternative tobacco products, similar to a 90-min in-laboratory self-administration task.

Association of electronic nicotine delivery system (ENDS) and cigarette solo and dual use with alcohol-related consequences among US adults.

INTRODUCTION: Research reports a robust association between combustible cigarette use and alcohol use frequency and severity. Extension to the emerging landscape of electronic nicotine delivery system (ENDS) use is needed to inform prevention and treatment strategies. METHOD: We evaluated data from the 2020 National Survey on Drug Use and Health (NSDUH). Respondents included adults reporting cigarettes or ENDS solo or dual use. Multivariable logistic regression models evaluated associations with alcohol use disorder (AUD) and alcohol-related risky behavior (i.e., heavy drinking, binge alcohol use, and driving after drinking) compared to never use controls and respondents with a history, but not current, use of cigarettes or ENDS. RESULTS: Multivariable models showed greater odds of AUD for respondents with dual ENDS and cigarette use (AOR = 10.2), ENDS use (AOR = 6.27), cigarette use (AOR = 4.45), and a history, but not ongoing, use (AOR = 2.60) relative to respondents with no use history. Similarly, respondents with dual use (AOR = 3.94), ENDS use (AOR = 2.41), and cigarette use (AOR = 1.71) had greater odds of AUD relative to those with a history of, but not ongoing, use. The association between dual use and AUD was greater for adults ages 21-25 (AOR = 16.2) than for adults over 25 (AOR = 7.82). Cigarette and ENDS solo and dual-use were similarly associated with greater odds of alcohol-related risky behavior relative to control groups. CONCLUSION: These findings demonstrate that nicotine use and dual use may be associated with indicators of problematic drinking. These results offer insight into emerging licit polysubstance profiles and call for mechanistic research to inform prevention and intervention efforts.

Reliability and validity of behavioral-economic measures: A review and synthesis of discounting and demand.

This review sought to synthesize the literature on the reliability and validity of behavioral-economic measures of demand and discounting in human research, introduce behavioral-economic research methodologies for studying addictive behaviors, discuss gaps in the current literature, and review areas for future research. A total of 34 studies was included in this review. The discounting literature showed similar responding regardless of whether hypothetical or actual outcomes were used, though people tended to discount the outcome presented first more steeply, suggesting order effects. Although delay-discounting measures seem to show temporal stability, exceptions were found for probability- and experiential-discounting tasks. The demand literature also demonstrated similar responding regardless of outcome type; however, some demand indices showed exceptions. Randomized price sequences tended to show modest increases in Omax and α and modestly higher rates of inconsistent or nonsystematic responses compared with sequential price sequences. Demand indices generally showed temporal stability, although the stability was weaker the larger the time interval between test sessions. Future studies would benefit by examining addictive commodities beyond alcohol, nicotine, and money; examining temporal stability over longer time intervals; using larger delays in discounting tasks; and using larger sample sizes.

Temporal reliability and stability of delay discounting: A 2-year repeated assessments study of the Monetary Choice Questionnaire.

The Monetary Choice Questionnaire (MCQ) is one of the most commonly used measures to assess delay discounting of reward. Reliable measurement by the MCQ is necessary for use in experimental settings or prognostic validity within clinical contexts. The present analysis expands prior work to evaluate temporal reliability and stability over an extended period, including repeated measurements, a larger and more broadly representative sample, and demonstrations of covariation with clinically significant health behaviors (e.g., cigarette use, COVID-19 vaccination, body mass index). Participants (N = 680; 55.6% female) were recruited through crowdsourcing and completed the MCQ approximately quarterly over 2 years. Measures of reliability, stability, and correlations with clinical constructs were determined for each timepoint and pairwise comparison. Test-retest reliabilities were high across all pairwise comparisons (all rxx > .75; range = .78-.86; mean = .83). Stability was also high with within-subject effect size differences all within a less-than-small effect size range (range dz = -0.09 to 0.19; mean = 0.04). Positive associations between smoking status and delay discounting rates were observed consistent with prior clinical studies. These findings of test durability support the use of MCQ administration for repeated measurement of delay-constrained choice as a stable respondent characteristic and illustrate its association with important health behaviors over extended time periods. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Substance-related cross-commodity purchase tasks: A systematic review.

OBJECTIVE: In the context of behavioral economics, drug use is a choice to which an individual may allocate responding despite the presence of alternative response possibilities. To examine the demand for a drug in an environment in which other drugs or nondrug alternatives are present, researchers often use a cross-commodity purchase task. These tasks allow participants to make choices across several reinforcers at varied unit prices and may elucidate behavioral economic patterns of substitutability and complementarity. The objective of this study was to conduct a systematic review of cross-commodity purchase task studies with human participants. METHOD: Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we screened 46 full-text studies (from 456 total records obtained from PsycINFO and PubMed databases and reference list search), yielding a final sample of 35 studies. RESULTS: The drug category with the largest number of studies assessed was tobacco and nicotine products. The most consistent economic relationships found were substitutability of traditional cigarettes by e-cigarettes and e-liquid, and both legal and illegal cannabis for the other; however, other substitutable and complementary relationships were observed (e.g., substitution of food for cigarettes, a complementary relationship between alcohol and cannabis). CONCLUSIONS: We discuss the implications of the results of this review from a treatment and harm reduction standpoint, highlight areas for future research particularly among drug categories with few studies and evaluating ecological validity of hypothetical measures, and make best practice recommendations for future cross-commodity drug-related purchase task research. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Tobacco-free policy reduces combustible tobacco byproduct on a large university campus.

Policy drives community-level behavior change, so behavior analysts should aid empirical policy development. University campus regulation is a useful proxy for broader policy initiatives and thus is a convenient inroad for behavior analyst involvement. This paper examines behavior analytic contributions to the planning and evaluation of a university tobacco-free initiative. We provided resources and guidance throughout early planning, and we then evaluated faculty and student compliance via byproduct (e.g., cigarette butts) counts taken at four high-traffic sites (as flagged by preliminary surveying of campus faculty, staff, and students). Visual analysis and supplementary statistical testing support notions of (a) a meaningful and sustained reduction of combustible tobacco byproducts in all locations, and (b) a demonstrative example of behavior analytic involvement with university policy planning and evaluation.

Leveraging the cigarette purchase task to understand relationships between cumulative vulnerabilities, the relative reinforcing effects of smoking, and response to reduced nicotine content cigarettes.

We examined if the relative-reinforcing effects of smoking increase with greater cumulative vulnerability and whether cumulative vulnerability moderates response to reduced nicotine content cigarettes. Participants were 775 adults from randomized clinical trials evaluating research cigarettes differing in nicotine content (0.4, 2.4, 15.8 mg/g). Participants were categorized as having low (0-1), moderate (2-3), or high (≥4) cumulative vulnerability. Vulnerabilities included rural residence, opioid use disorder, affective disorder, low educational attainment, poverty, unemployment, and physical disability. We used the cigarette purchase task (CPT) to assess the relative-reinforcing effects of participants' usual-brand cigarettes at baseline and study cigarettes during the 12-week trial. The CPT is a behavioral-economic task wherein participants estimate likely smoking (demand) over 24 h under escalating cigarette price. Demand is characterized by two factors: Amplitude (demand volume at zero/minimal price) and Persistence (demand sensitivity to price). Greater cumulative vulnerability was associated with greater demand Amplitude (F[2709] = 16.04,p < .0001) and Persistence (F[2709] = 8.35,p = .0003) for usual-brand cigarettes. Demand Amplitude for study cigarettes increased with increasing cumulative vulnerability (F[2619] = 19.59, p < .001) and decreased with decreasing nicotine content ([4879] = 5.45, p < .001). The only evidence of moderation was on demand Persistence (F[8867] = 2.00,p = .04), with larger reductions at the 0.4 mg/g compared to 15.8 mg/g doses among participants with low compared to moderate or high cumulative vulnerability. The relative-reinforcing effects of smoking clearly increase with greater cumulative vulnerability. Reducing nicotine content would likely reduce demand Amplitude across cumulative-vulnerability levels but reductions in demand Persistence may be more limited among those with greater cumulative vulnerability.

Delay discounting and neurocognitive performance in young adults with differential patterns of substance use: Findings from the Human Connectome Project.

A large proportion of individuals who use psychoactive substances regularly use more than one substance. This pattern of behavior, termed polysubstance use, is associated with greater risks than when consuming only a single substance. The present study examined delay discounting, neurocognitive functioning, and demographic indicators among a large, racially and socioeconomically diverse sample of young adults drawn from the Human Connectome Project who reported either non, mono, or dual use of alcohol, tobacco, and/or cannabis. Univariate and multivariate tests suggested individuals who reported using multiple substances were more likely to be male, experienced higher rates of alcohol use disorder, and, when reporting both alcohol use and cannabis involvement, scored lower on a measure of inhibitory control relative to those who reported mono or dual use of alcohol and/or cigarettes. Individuals who reported currently smoking cigarettes exhibited the steepest discounting irrespective of other substances used; however, we observed additive effects for alcohol use and, to a lesser extent, cannabis involvement. Specifically, steeper discounting occurred when individuals who reported either regular alcohol use or > 100 lifetime instances of cannabis use also reported smoking cigarettes. We discuss several hypotheses for this finding related to the diversity of the sample and substances assessed as well as directions for future programmatic lines of research. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Single- and cross-commodity discounting among adults who use alcohol and cannabis: Associations with tobacco use and clinical indicators.

BACKGROUND: Delay discounting assessments typically involve choices between an immediate outcome and a larger amount of the same outcome after a delay. Real-world choices, however, more often involve qualitatively different alternatives. The primary aim of this study was to examine single- and cross-commodity discounting of money, alcohol, and cannabis, along with clinical measures of alcohol and cannabis use among people who use both alcohol and cannabis, yet differ in tobacco cigarette smoking status (i.e., dual- versus tri-use). METHODS: An online crowdsourced sample (N = 318) of people who reported using alcohol and cannabis in the past week completed single- and cross-commodity discounting assessments across each combination of money, alcohol, and cannabis. We recruited a balanced number of people who did and did not also use tobacco cigarettes and examined associations between discounting, tobacco use, and clinical indicators. RESULTS: People who reported using tobacco cigarettes in addition to alcohol and cannabis tended to engage in significantly higher rates of harmful alcohol and cannabis use than those who reported using only alcohol and cannabis. Cross-commodity discounting was significantly associated with patterns of harmful alcohol and cannabis use while no associations emerged for single-commodity discounting. CONCLUSIONS: Cross-commodity discounting provides a nuanced account of intertemporal choice by incorporating relative commodity valuation and appears to characterize harmful alcohol and cannabis use more clearly than single-commodity arrangements. Further cross-commodity research is needed to better understand the interplay between temporal location and relative commodity value among people who use multiple substances.

Dual use of alcohol and cannabis among college students: A reinforcer pathologies approach.

The reinforcer pathologies model proposes 2 behavioral economic constructs interact in addiction: operant demand and delay discounting. These constructs manifest as behavioral markers of addiction in the form of excessive reinforcer value and strong preference for immediate access and consumption of this reinforcer despite suboptimal long-term outcomes. The first aim of this investigation was to identify the degree to which delay discounting (of money and alcohol) and demand for alcohol differ between college student drinkers (N = 185) who do and do not co-use cannabis. As a second aim, we sought to replicate the 2-factor solution for alcohol and cannabis demand within a college sample. Results suggest dual users have significantly stronger Persistence and Amplitude for alcohol, demonstrate steeper delay discounting of alcoholic drinks, and are at greater risk for alcohol use disorder than individuals who drink yet do not use cannabis. These results provide further support for the reinforcer pathologies model and contribute to the literature on dual-substance use in the college population. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Comparing participant estimated demand intensity on the cigarette Purchase Task to consumption when usual-brand cigarettes were provided free.

Accumulating evidence suggests that the hypothetical Cigarette Purchase Task (CPT), especially its demand Intensity index (i.e., estimated cigarettes participants would smoke if free), is associated with individual differences in smoking risk. Nevertheless, few studies have examined the extent to which hypothetical CPT demand Intensity may differ from consumption when participants are provided with free cigarettes. That topic is the overarching focus of the present study. Participants were 745 adult smokers with co-morbid psychiatric conditions or socioeconomic disadvantage. CPT was administered for usual-brand cigarettes prior to providing participants with seven days of their usual-brand cigarettes free of cost and consumption was recorded daily via an Interactive Voice Response (IVR) System. Demand Intensity was correlated with IVR smoking rate (rs 0.670-0.696, ps < 0.001) but estimates consistently exceeded IVR smoking rates by an average of 4.4 cigarettes per day (ps < 0.001). Importantly, both measures were comparably sensitive to discerning well-established differences in smoking risk, including greater cigarettes per day among men versus women (F(1,732) = 18.74, p < 0.001), those with versus without opioid-dependence (F(1,732) = 168.37, p < 0.001), younger versus older adults (F(2,730) = 32.93, p < 0.001), and those with lower versus greater educational attainment (F(1,732) = 38.26, p < 0.001). Overall, CPT demand Intensity appears to overestimate consumption rates relative to those observed when participants are provided with free cigarettes, but those deviations are systematic (i.e., consistent in magnitude and direction, Fs all <1.63; ps > 0.19 for all interactions with subgroups). This suggests that demand Intensity was sensitive to established group differences in smoking rate, supporting its utility as an important measure of addiction potential.

Behavioral economic measurement of cigarette demand: A descriptive review of published approaches to the cigarette purchase task.

The cigarette purchase task (CPT) is a behavioral economic method for assessing demand for cigarettes. Growing interest in behavioral correlates of tobacco use in clinical and general populations as well as empirical efforts to inform policy has seen an increase in published articles employing the CPT. Accordingly, an examination of the published methods and procedures for obtaining these behavioral economic metrics is timely. The purpose of this investigation was to provide a review of published approaches to using the CPT. We searched specific Boolean operators (["behavioral economic" AND "purchase task"] OR ["demand" AND "cigarette"]) and identified 49 empirical articles published through the year 2018 that reported administering a CPT. Articles were coded for participant characteristics (e.g., sample size, population type, age), CPT task structure (e.g., price framing, number and sequence of prices; vignettes, contextual factors), and data analytic approach (e.g., method of generating indices of cigarette demand). Results of this review indicate no standard approach to administering the CPT and underscore the need for replicability of these behavioral economic measures for the purpose of guiding clinical and policy decisions. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Latent Structure of the Cigarette Purchase Task Among Treatment-Seeking Smokers With Depression and Its Predictive Validity on Smoking Abstinence.

INTRODUCTION: Research has recently shown that nicotine reinforcement is better characterized by a bifactorial latent structure: persistence (insensitivity to cigarette pricing) and amplitude (consumption at inexpensive prices). No study to date has examined its value as a predictor of abstinence. This study aimed to provide new evidence on the latent structure of the cigarette purchase task (CPT) in smokers with depressive symptoms and to examine whether the latent structure performs better as a predictor of continuous abstinence than do the individual indices. METHODS: Participants (n = 205 smokers; 72% female: Beck Depression Inventory, Second Edition, M = 24.68, SD = 10.45) were randomized to two smoking cessation treatments for quitting smoking: cognitive behavioral treatment (CBT) or CBT + contingency management (CM). A principal-components analysis was conducted to examine the latent structure of the CPT and a set of regression models were performed to assess its predictive validity. RESULTS: The principal-components analysis revealed a bifactorial solution, which was interpreted as persistence (breakpoint, Omax, Pmax, and elasticity) and psychological inertia (intensity and elasticity of demand). Evidence on the convergent validity was obtained through significant associations between the two latent factors and smoking variables (all r values ≥.17). Psychological inertia was negatively related to the number of days of continuous abstinence at the end of treatment regardless of the treatment condition [R2 = .038; F(2, 202) = 4.989, p = .008]. CONCLUSIONS: Psychological inertia informs on which patients benefit less from smoking cessation treatments incorporating CM and CBT. Treatment components that affect individuals' excessive valuation of cigarettes might improve cessation outcomes. IMPLICATIONS: This is the first attempt to examine the latent structure of the CPT in depressed smokers and to yield evidence on its predictive validity. A specific bifactorial solution exists for this population: persistence (breakpoint, Omax, Pmax, and elasticity) and psychological inertia (intensity and elasticity). Isolating demand indices and factors provides a high-resolution characterization of nicotine reinforcement for depressed smokers in that it informs on treatment response. Compared to the individual CPT indices, psychological inertia more effectively predicts which patients benefit most from either CM or CBT. Treatment components that affect individuals' excessive valuation of cigarettes (eg, episodic future thinking) should be integrated into smoking cessation treatments.

Sensitivity of hypothetical purchase task indices when studying substance use: A systematic literature review.

Hypothetical Purchase Tasks (HPTs) simulate demand for a substance as a function of escalating price. HPTs are increasingly used to examine relationships between substance-related correlates and outcomes and demand typically characterized using a common battery of indices (Intensity, Omax, Pmax, Breakpoint, Elasticity). This review examines the relative sensitivity of the HPT indices. Reports were identified using the search term "purchase task" in PubMed and Web of Science. For inclusion, reports had to be original studies in English, examine relationships between HPT indices and substance-related correlates or outcomes, and appear in a peer-reviewed journal through December 2017. Indices were compared using effect sizes (Cohen's d) and the proportion of studies in which statistically significant relationships were observed. The search identified 1274 reports with 114 (9%) receiving full-text review and 82 (6%) meeting inclusion criteria. 41 reports examined alcohol, 34 examined cigarettes/nicotine products, and 10 examined other substances. Overall, statistically significant relationships between HPT indices and substance-related correlates and outcomes were most often reported for Intensity (88.61%, 70/79), followed by Omax (81.16%, 56/69), Elasticity (72.15%, 57/59), Breakpoint (62.12%, 41/66), and Pmax (48.08%; 25/52). The largest effect sizes were observed for Intensity (0.75 ±â€¯0.04, CI 0.67-0.84) and Omax (0.64 ±â€¯0.04, CI 0.56-0.71), followed by Elasticity (0.44 ±â€¯0.04, CI 0.37-0.51), Breakpoint (0.30 ±â€¯0.03, CI 0.25-0.36), and Pmax (0.25 ±â€¯0.04, CI 0.18-0.33). Patterns were largely consistent across substances. In conclusion, HPTs can be highly effective in revealing relationships between demand and substance-related correlates and outcomes, with Intensity and Omax exhibiting the greatest sensitivity.

An exact solution for unit elasticity in the exponential model of operant demand.

Research applying the behavioral economic demand framework is increasingly conducted across disciplines. With respect to psychopharmacology and substance abuse, real and hypothetical purchase tasks are regularly used to evaluate the demand for various substances and reinforcers, such as alcohol. At present, a variety of methods has been introduced to solve for the point of unit elasticity, or Pmax, in the exponential model of demand; however, these methods vary in their potential for error. Current methods for determining Pmax are presented here and a novel exact solution for Pmax in the exponential model of demand is introduced. This solution provides an exact calculation of Pmax using the omega function, as algebraic solutions are not possible. This novel approach is introduced, discussed, and systematically compared to earlier methods for determining Pmax using computer simulations and reanalyses of published study data. Systematic comparison indicated that this new approach, an exact analytic solution for Pmax, provides results that are identical to computationally intensive Pmax methods that directly evaluate the slope of the demand function. The exact analytic Pmax approach is reviewed, its calculations explained, and an easy-to-use web tool is provided to assist researchers in easily performing this calculation of Pmax. Implications for reducing potential sources of error are reviewed and future directions are also discussed. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Evaluating the utility of the modified cigarette evaluation questionnaire and cigarette purchase task for predicting acute relative reinforcing efficacy of cigarettes varying in nicotine content.

BACKGROUND: Nicotine is the addictive component in cigarettes that maintain cigarette smoking that subsequently leads to morbidity and mortality. Methods for assessing the abuse liability of cigarettes are essential to inform new tobacco product standards. This secondary analysis evaluated the utility of one subjective effects measure, the modified Cigarette Evaluation Questionnaire (mCEQ), and one behavioral economic task, the Cigarette Purchase Task (CPT), for predicting acute relative reinforcing efficacy measured by concurrent choice Self-Administration (SA). METHODS: Smokers (N = 169) belonging to one of three vulnerable populations participated in a multi-site, double-blind study evaluating research cigarettes with varying levels of nicotine (0.4, 2.4, 5.2, 15.8 mg/g). Participants sampled cigarettes and completed the mCEQ and CPT. In subsequent sessions, cigarette preference was assessed using a concurrent choice SA procedure. Mixed-model repeated measures analysis of variance tests were used to evaluate the utility of the mCEQ subscales and CPT indices for predicting preference for the higher compared to lower nicotine content cigarettes. In addition, stepwise regressions were used to determine which subscales and indices independently predicted concurrent choice SA. RESULTS: Greater increases on the Satisfaction and Enjoyment of Respiratory Tract Sensations mCEQ subscales independently predicted higher dose preference in concurrent choice testing. Elasticity was the only CPT index that predicted choice. However, its predictive utility differed by dose among opioid-maintained individuals. CONCLUSION: The mCEQ and CPT predict behavioral measures of relative reinforcing efficacy as assessed in concurrent choice SA, with the mCEQ Satisfaction and Enjoyment of Respiratory Tract Sensations subscales being the strongest independent predictors.

Examining interrelationships between the Cigarette Purchase Task and delay discounting among pregnant women.

Two common behavioral economic simulation tasks used to study cigarette smoking are the Cigarette Purchase Task, a measure of cigarette demand, and delay discounting, a measure of the subjective value of rewards as a function of delays to delivery. Few studies have evaluated whether combining these tasks enhances understanding of smoking beyond either alone. The current study represents an initial evaluation of the intersection between cigarette demand indices and delay discounting among pregnant smokers by examining associations between these measures and whether a woman makes antepartum quit attempts before entering prenatal care (a reliable predictor of eventual quitting). Participants were 159 pregnant women enrolled in a smoking-cessation trial. Low O max and shallow discounting were each associated with antepartum quit attempts. Participants were next categorized into four subgroups (low O max , shallow discounting; low O max , steep discounting; high O max , shallow discounting; high O max , steep discounting) using median splits. Those with shallow discounting and low O max were more likely to have made quit attempts than each of the other three subgroups. That is, steep discounting appears to undermine the association of low O max and efforts to quit smoking during pregnancy while high O max overshadows any protective influence associated with shallow discounting.

Price elasticity of illegal versus legal cannabis: a behavioral economic substitutability analysis.

BACKGROUND AND AIMS: The evolving legal status of cannabis world-wide necessitates evidence-based regulatory policies to minimize risks associated with cannabis misuse. A prominent concern is the impact legalization may have on the illegal cannabis market, including whether illegal cannabis will serve as a substitute for legal cannabis. Empirical data on this issue are virtually non-existent. This study used behavioral economics to investigate substitutability of legal and illegal cannabis in legalized catchment areas in the United States. DESIGN: A substitution-based marijuana purchase task assessed estimated cannabis consumption from concurrently available legal (a dispensary) and illegal (a dealer) sources. Prices of the two options were reciprocally either held constant ($10/gram) or escalated ($0-$60/gram). SETTING: US states with legalized recreational cannabis. PARTICIPANTS: Adult cannabis users who were at least 21 years old (n = 724; mean age = 34.13; 52% female; 74% Caucasian) were recruited using online crowdsourcing. MEASUREMENTS: Mean consumption values were used in demand curve modeling to generate indices of price sensitivity and elasticity. Differences in demand indices were compared using extra sums-of-squares F-tests. FINDINGS: Both legal and illegal fixed-price cannabis options had significant positive cross-price elasticities (Ps < 0.001), indicating that higher prices motivate substitution irrespective of legality. However, the presence of a legal alternative had a substantially greater effect on consumption and elasticity of illegal cannabis (∆elasticity  = 0.0019; F(1,37)  = 160, P < 0.0001) than the presence of an illegal alternative on demand for legal cannabis (∆elasticity  = 0.0002; F(1,37)  = 48, P < 0.0001), indicating asymmetric substitution. Demand for legal cannabis was significantly greater than for illegal cannabis (P < 0.0001). CONCLUSIONS: Cannabis users treat legal cannabis as a superior commodity compared with illegal cannabis and exhibit asymmetric substitutability favoring legal product. Cannabis price policies that include somewhat higher consumer costs for legal cannabis relative to contraband (but not excessively higher costs) would not be expected to incentivize and expand the illegal market.

Elevated Behavioral Economic Demand for Alcohol in Co-Users of Alcohol and Cannabis.

OBJECTIVE: Co-use of cannabis and alcohol is associated with increased drinking and other negative consequences relative to use of alcohol alone. One potential explanation for these differences is overvaluation of alcohol (e.g., alcohol demand) among co-users, similar to established overvaluation of alcohol among tobacco and alcohol co-users. This study examined differences in alcohol demand between an alcohol and cannabis co-user group and an alcohol-only group. METHOD: A large sample of adult drinkers (n = 1,643, 54% female) was recruited through an online crowdsourcing site (Amazon Mechanical Turk). Of the full sample, 476 participants reported weekly or greater cannabis use in the past 6 months (co-user group); 888 reported never using cannabis in the past 6 months (alcohol-only group). Assessments included a validated alcohol purchase task and self-report measures of alcohol and cannabis use. RESULTS: Co-users reported significantly higher alcohol consumption across the elastic portion of the alcohol demand curve (i.e., $1.50-$9.00/drink). Analyses of covariance controlling for alcohol use and demographics revealed significantly higher breakpoint (p = .025) and Omax (p = .002) and significantly lower elasticity (p < .003) in the co-user group. Intensity and Pmax did not significantly differ between groups. CONCLUSIONS: Co-users of cannabis and alcohol overvalue alcohol compared with individuals who drink alcohol but do not use cannabis. This study is generally consistent with prior studies on alcohol and tobacco co-users, providing converging evidence that polysubstance use is associated with overvaluation of alcohol. These findings have important implications for treatment and prevention, particularly in the context of changes in cannabis legalization.