Longitudinal examination of alcohol demand and alcohol-related reinforcement as predictors of heavy drinking and adverse alcohol consequences in emerging adults.

BACKGROUND AND AIMS: Behavioral economic theory predicts that high alcohol demand and high proportionate alcohol-related reinforcement are important determinants of risky alcohol use in emerging adults, but the majority of research to date has been cross-sectional in nature. The present study investigated prospective and dynamic relationships between alcohol demand and proportionate alcohol-related reinforcement in relation to heavy drinking days and alcohol problems. DESIGN: Longitudinal cohort with assessments every 4 months for 20 months. SETTING: Ontario, Canada. PARTICIPANTS: Emerging adults reporting regular heavy episodic drinking (n = 636, Mage = 21.44; 55.8% female). MEASUREMENTS: Heavy drinking days (HDD; Daily Drinking Questionnaire), alcohol problems (Brief Young Adult Alcohol Consequences Questionnaire), alcohol demand (Alcohol Purchase Task) and proportionate alcohol-related reinforcement (Activity Level Questionnaire). FINDINGS: Linear mixed effects models revealed that behavioral economic indicators and alcohol-related outcomes significantly decreased over the study, consistent with 'aging out' of risky alcohol use. Random intercept cross-lagged panel models revealed significant between-person relationships, such that higher alcohol demand and alcohol-related reinforcement were positively associated with HDD and alcohol problems (random intercepts = 0.187-0.534, Ps < 0.01). Moreover, alcohol demand indicators (particularly the rate of change in elasticity of the demand curve, as measured by α, and the maximum expenditure, Omax) and proportionate alcohol-related reinforcement significantly forecasted changes in HDD at all time points (|ßs| = 0.063-0.103, Ps < 0.05) in cross-lagged relationships, with bidirectional associations noted for the rate of change in elasticity (ßs = -0.085 to -0.104, Ps < 0.01). Proportionate alcohol-related reinforcement also significantly forecasted changes in alcohol problems at all time points (ßs = 0.072-0.112, Ps < 0.01). CONCLUSIONS: Multiple behavioral economic indicators (demand elasticity, maximum expenditure and reinforcement ratio) forecast changes in heavy episodic drinking and alcohol problems over the course of emerging adulthood. These results further implicate alcohol demand and proportionate alcohol-related reinforcement as etiologically and developmentally important mechanisms in alcohol use trajectories.

Applying behavioral economics to understand changes in alcohol outcomes during the transition to adulthood: Longitudinal relations and differences by sex and race.

OBJECTIVE: Population drinking trends show clear developmental periodicity, with steep increases in harmful alcohol use from ages 18 to 22 followed by a gradual decline across the 20s, albeit with persistent problematic use in a subgroup of individuals. Cross-sectional studies implicate behavioral economic indicators of alcohol overvaluation (high alcohol demand) and lack of alternative substance-free reinforcers (high proportionate alcohol-related reinforcement) as potential predictors of change during this developmental window, but longitudinal evidence is sparse. METHOD: Using a sample of emerging adults (N = 497, Mage = 22.61 years, 62% female, 48.69% White, 40.44% Black), this study examined prospective, bidirectional relations between both past-week heavy drinking days (HDD) and alcohol problems and proportionate alcohol-related reinforcement (reinforcement ratio), alcohol demand intensity (consumption at zero price), alcohol demand Omax (maximum expenditure), and change in demand elasticity (rate of change in consumption across escalating price) over five assessments (every 4 months) using random intercept cross-lagged panel models. RESULTS: Alcohol problems and HDD decreased across assessments. Significant between-person effects indicated that each behavioral economic variable was associated with increased drinking risk. Change in reinforcement ratio was positively associated with decreases in alcohol problems. Multigroup invariance modeling revealed distinct risk pathways in that change in demand intensity and Omax predicted change in alcohol problems for male participants and change in intensity predicted change in alcohol problems for non-White participants. CONCLUSION: The study provides consistent support for proportionate alcohol-related reinforcement and mixed support for demand as within-person predictors of reductions in drinking. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

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.

Incorporating socioeconomic status into studies on delay discounting and health via subjective financial status: An initial validation in tobacco use.

Delayed reward discounting (DRD) refers to the extent to which an individual devalues a reward based on its delay in time and has been linked to a wide variety of health behaviors. Because it is commonly measured using monetary rewards, income is typically used as a covariate to adjust for a person's socioeconomic status. Standard financial income measures have several limitations, such as not incorporating pertinent considerations like cost of living or number of financial dependents. This study examined a novel subjective financial status measure that uses a simple omnibus self-attribution as an alternative strategy. The novel measure was examined in the context of tobacco involvement and compared with a traditional objective measure in two samples, one comprising 1,430 community-recruited adults (Mage = 38.9, 58.3% female) and the other comprising 852 adult daily smokers (Mage = 31.1, 38% female). Associations between DRD, subjective and objective income measures, and cigarette dependence were explored using correlational analyses, equivalence testing, and hierarchical linear regressions. Correlations revealed subjective income was robustly positively correlated with traditional income (rs = .52-.56) and had stronger associations with DRD and cigarette dependence compared to traditional income. Equivalence testing and multiple hierarchical regressions found subjective income to be statistically equivalent or superior to the traditional income measure. These findings provide initial support for the utility of this novel subjective income measurement to account for economic status in research on DRD and health. (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).

Income shock increases preferences for smaller immediate rewards and reduces alcohol demand among a sample of crowd-sourced adults.

In behavioral economics, income shock manipulations (hypothetical narratives where money is gained or lost) can provide meaningful insight into decision-making related to primary and secondary commodities. To date, few studies have examined the impact of income shock on delay discounting in healthy controls and individuals using substances, and no study to date has examined the impact of income shock on alcohol demand. This study examined the effects of income shock on behavioral economic assessments (i.e., delay discounting and alcohol demand) among a sample of adult participants recruited via Amazon Mechanical Turk (N = 140). The sample was predominantly middle-aged, male, and White (mean age = 38.81; 37.1% female; 77.1% White). Participants were randomly assigned to one of three income shock narratives (negative, neutral, positive). They completed two versions of the 5-choice delay discounting task for $100 and $1,000 and an alcohol purchase task (APT) before and after the income shock narrative. Following negative income shock, preferences for smaller immediate rewards increased in the $100 version of the discounting task and decreased the price at which alcohol consumption was suppressed to zero (i.e., break point). Sensitivity to price changes in the APT decreased following neutral and positive income shock but not the negative condition. Results replicate and extend prior findings examining the impact of income shock on delay discounting. Furthermore, this is the first study to study income shock effects on alcohol demand. Findings suggest that primary commodity manipulation (i.e., money) can potentially impact decision-making regarding secondary commodities (i.e., alcohol). (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Next-day responsibilities attenuate demand for alcohol among a crowdsourced sample of community adults.

While several studies have examined how class time and internship responsibilities impact demand for alcohol in undergraduate samples, no study has examined this question using more universally applicable responsibilities with a sample of community adults. Therefore, the aim of this study was to examine the impact of a range of next-day responsibilities on demand for alcohol among a crowdsourced sample of community adults using a hypothetical alcohol purchase task (APT). Community adults (n = 261; 79% White; 60% identified as men; 39% identified as women; and 1% identified as nonbinary) with a mean age of 38.42 recruited from Amazon Mechanical Turk rank-ordered eight hypothetical next-day responsibilities across three categories (i.e., work, caregiving, and recreational). Participants first completed a standard APT with no explicit next-day responsibilities, followed by purchase tasks in the context of their two highest ranked responsibilities. All participants needed to pass several stages of attention and data quality checks to be included in the final sample. All observed demand indices (i.e., intensity, breakpoint, Omax, and Pmax) were significantly higher in the no responsibilities condition compared to both the first- and second-ranked responsibility condition (ps < .001); however, there was no significant difference in any demand index between the first- and second-ranked responsibility (p range .65-.91). These results extend prior work by demonstrating engagement with substance-free alternatives may reduce demand for alcohol among community adults. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Alcohol cues increase behavioral economic demand and craving for alcohol in nontreatment-seeking and treatment-seeking heavy drinkers.

BACKGROUND: Behavioral economic research has revealed significant increases in alcohol demand following exposure to alcohol-related cues. Prior research has focused exclusively on nontreatment-seeking heavy drinkers, included only male participants, or used heterogeneous methods. The current studies sought to replicate and extend existing findings in treatment-seeking and nontreatment-seeking heavy drinkers while also examining sex effects and moderation by alcohol use disorder (AUD) severity. METHODS: Study 1 included 117 nontreatment-seeking heavy drinkers (51.5% women; M age 34.69; 56.4% AUD+), and Study 2 included 89 treatment-seeking heavy drinkers with AUD (40.4% women; M age = 41.35). In both studies, alcohol demand was measured using a hypothetical alcohol purchase task (APT), and subjective alcohol craving was measured using visual analog scales. Measures were collected following exposure to neutral (water) cues in a standard room and alcohol cues in a bar lab. RESULTS: Alcohol demand (intensity, Omax , breakpoint, and elasticity) and craving were significantly increased following alcohol cues compared to neutral cues (ps < 0.005) with effect sizes ranging from small to large (ηp 2 = 0.074-0.480). Participants with AUD (Study 1) or with higher AUD severity (Study 2) reported higher craving and higher demand for most indices (i.e., main effects; ps < 0.032, ηp 2 = 0.043-0.239). A larger alcohol cue increase in Omax was found for AUD+ participants in Study 1 compared to non-AUD participants (p = 0.028, ηp 2 = 0.041) but not for any other indices in Study 1 or Study 2. There were no significant sex effects. CONCLUSIONS: These findings replicate and extend prior research by offering additional insight into alcohol cue effects on the reinforcing value of alcohol and subjective motivation to drink. The results also suggest that sex and AUD severity do not meaningfully impact cue effects across most indices of demand.

Applied behavioral economics and public health policies: Historical precedence and translational promise.

Behavioral economics is an approach to understanding behavior though integrating behavioral psychology and microeconomic principles. Advances in behavioral economics have resulted in quick-to-administer tasks to assess discounting (i.e., decrements in the subjective value of a commodity due to delayed or probabilistic receipt) and demand (i.e., effort exerted to defend baseline consumption of a commodity amidst increasing constraints)-these tasks are built upon decades of foundational work from the experimental analysis of behavior and exhibit adequate psychometric properties. We propose that the behavioral economic approach is particularly well suited, then, for experimentally evaluating potential public policy decisions, particularly during urgent times or crises. Using examples from our collaborations (e.g., cannabis legalization, happy hour alcohol pricing, severe weather alerts, COVID-19 vaccine marketing), we demonstrate how behavioral economic approaches have rendered novel insights to guide policy development and garnered widespread attention outside of academia. We conclude with implications on multidisciplinary work and other areas in need of behavioral economic investigations.

Delayed Reward Discounting as a Prognostic Factor for Smoking Cessation Treatment Outcome: A Systematic Review.

INTRODUCTION: While large proportions of smokers attempt to quit, rates of relapse remain high and identification of valid prognostic markers is of high priority. Delayed reward discounting (DRD) is a behavioral economic index of impulsivity that has been associated with smoking cessation, albeit inconsistently. This systematic review sought to synthesize the empirical findings on DRD as a predictor of smoking cessation treatment outcome, to critically appraise the quality of the literature, and to propose directions for future research. AIMS AND METHODS: A total of 734 articles were identified, yielding k = 14 studies that met the eligibility criteria. The Quality in Prognosis Studies (QUIPS) tool was used to assess methodological quality of the included studies. RESULTS: Individual study methods were highly heterogeneous, including substantial variation in research design, DRD task, clinical subpopulation, and treatment format. The predominant finding was that steeper DRD (higher impulsivity) was associated with significantly worse smoking cessation outcomes (10/14 studies). Negative results tended to be in pregnant and adolescent subpopulations. The QUIPS results suggested low risk of bias across studies; 11/14 studies were rated as low risk of bias for 5/6 QUIPS domains. CONCLUSIONS: This review revealed consistent low-bias evidence for impulsive DRD as a negative prognostic predictor of smoking cessation treatment outcome in adults. However, methodological heterogeneity was high, precluding meta-analysis and formal tests of small study bias. The prospects of targeting impulsive DRD as a potentially modifiable risk factor or providing targeted treatment for smokers exhibiting high levels of discounting are discussed. IMPLICATIONS: These findings indicate consistent evidence for DRD as a negative prognostic factor for smoking cessation outcome in adults. As such, DRD may be a useful as a novel treatment target or for identifying high-risk populations requiring more intensive treatment.

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).

Experimental manipulations of behavioral economic demand for addictive commodities: a meta-analysis.

BACKGROUND AND AIMS: Reinforcing value, an index of motivation for a drug, is commonly measured using behavioral economic purchase tasks. State-oriented purchase tasks are sensitive to phasic manipulations, but with heterogeneous methods and findings. The aim of this meta-analysis was to characterize the literature examining manipulations of reinforcing value, as measured by purchase tasks and multiple-choice procedures, to inform etiological models and treatment approaches METHODS: A random-effects meta-analysis of published findings in peer-reviewed articles. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) protocol, studies were gathered through searches in PsycINFO and PubMed/MEDLINE (published 22 May 2018). Searches returned 34 unique studies (aggregate sample n = 2402; average sample size = 68.94) yielding 126 effect sizes. Measurements included change (i.e. Cohen's d) in six behavioral economic indices (intensity, breakpoint, Omax , Pmax , elasticity, cross-over point) in relation to six experimental manipulations (cue exposure, stress/negative affect, reinforcer magnitude, pharmacotherapy, behavioral interventions, opportunity cost). RESULTS: Cue exposure (d range = 0.25-0.44, all Ps < 0.05) and reinforcer magnitude [d = 0.60; 95% confidence interval (CI) = 0.18, 1.01; P < 0.005] manipulations resulted in significant increases in behavioral economic demand across studies. Stress/negative affect manipulations also resulted in a small, significant increase in Omax (d = 0.18; 95% CI = 0.01, 0.34; P = 0.03); all other effect sizes for negative affect/stress were non-significant, albeit similar in size (d range = 0.14-0.18). In contrast, pharmacotherapy (d range = -0.37 to -0.49; Ps < 0.04), behavioral intervention (d = -0.36 to -1.13) and external contingency (d = -1.42; CI = -2.30, -0.54; P = 0.002) manipulations resulted in a significant decrease in intensity. Moderators (substance type) explained some of the heterogeneity in findings across meta-analyses. CONCLUSIONS: In behavioral economic studies, purchase tasks and multiple-choice procedures appear to provide indices that are sensitive to manipulations found to influence motivation to consume addictive substances in field experiments.

Technological advances in the assessment of impulse control in offenders: A systematic review.

Deficits in impulse control have been linked to criminal offending, risk of recidivism, and other maladaptive behaviours relevant to the criminal justice system (e.g. substance use). Impulse control can be conceptualized as encompassing the broad domains of response inhibition and impulsive/risky decision-making. Advancements in technology have led to the development of computerized behavioural measures to assess performance in these domains, such as go/no-go and delay discounting tasks. Despite a relatively large literature examining these tasks in offenders, findings are not universally consistent. This systematic review aims to synthesize the literature using computerized neurocognitive tasks to assess two domains of impulse control in offenders: response inhibition and impulsive/risky decision-making. The review included 28 studies from diverse geographic locations, settings, and offender populations. The results largely support the general conclusion that offenders exhibit deficits in impulse control compared with non-offenders, with studies of response inhibition more consistently reporting differences than studies using impulsive and risky decision-making tasks. Findings are discussed in the context of contemporary neuroimaging research emphasizing dysfunction in prefrontal cortex as a key contributor to impulse control deficits in offenders.

Correction to: Availability of legalized cannabis reduces demand for illegal cannabis among Canadian cannabis users: evidence from a behavioural economic substitution paradigm.

The published version of Fig. 1 contained a mistake in the colour scale for the vertical lines and corresponding labels for the Pmax values.

Availability of legalized cannabis reduces demand for illegal cannabis among Canadian cannabis users: evidence from a behavioural economic substitution paradigm.

In the context of cannabis legalization, an important question among clinicians, policymakers, and the public is whether availability of legal cannabis will significantly reduce consumption (demand) of illegal cannabis. Using paradigms from behavioural economics, we tested the prediction that legal cannabis would be an asymmetrical substitute for illegal cannabis, with legal cannabis operating as a superior commodity based on its regulated status. In a sample of 289 adult cannabis users in Ontario, we found evidence of substitutability for both legal and illegal cannabis, but significantly lower substitutability of illegal for legal cannabis, a pattern that was also present for price elasticity (α) and Pmax. Thus, the data indicated asymmetric substitution such that the availability of legal cannabis substantially decreased demand for illegal cannabis, but a significantly smaller effect in reverse. These results suggest that the introduction of legal cannabis into the market may disrupt and reduce illegal purchases, contributing to the reduction of the potential harms associated with the illegal market. However, in revealing price windows in which legal cannabis is preferred over the contraband alternative, these data also have significant implications for pricing policies.

Elevated cannabis demand is associated with driving after cannabis use in a crowd-sourced sample of adults.

Epidemiological and roadside studies suggest that driving after cannabis use (DACU) is prevalent in the United States, and rates have increased following legalization or decriminalization of cannabis in some U.S. states. Reinforcing value of addictive substances (as measured by behavioral economic demand tasks), is an emerging risk factor for driving under the influence. This study sought to expand upon the previously documented link between alcohol demand and driving after drinking by examining whether similar associations exist between cannabis demand and DACU. A large diverse sample of adults (N = 733) recruited via an online crowd-sourcing platform (Amazon Mechanical Turk) competed a validated marijuana purchase task assessing cannabis consumption across a range of prices and validated assessments of DACU, cannabis misuse, and demographics. In analyses of covariance controlling for age, sex, income, and level of cannabis misuse, individuals who endorsed DACU showed elevated cannabis demand across all demand indices examined (ps < .05). Logistic regression indicated that increased intensity of demand was uniquely associated with a greater likelihood of DACU (odds ratio [OR] = 1.61-2.02, ps < .03). Breakpoint, maximum expenditure, and price point corresponding to maximum expenditure uniquely predicted DACU in separate models (OR = 1.41-1.68, ps < .03) but not in a combined model (ORs < 1.36, ps > .47). These results provide initial evidence that elevated cannabis demand may be a distal risk factor for DACU, but future research is needed to clarify the specific relationship between cannabis demand and DACU. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Validation of a brief behavioral economic assessment of demand among cigarette smokers.

Basic and clinical addiction research use demand measures and analysis extensively to characterize drug use motivations. Hence, obtaining an accurate and brief measurement of demand that can be easily utilized in different settings is highly valued. In the current study, 2 versions of a breakpoint measure, designed to capture cigarette demand, were investigated in 119 smokers who were recruited from an online crowdsourcing platform. The first version determines the maximum price a smoker is willing to pay for one cigarette received right now when paid out of pocket, and the second determines the maximum price when paid using a hypothetical $100 gift card received for free. The breakpoint measures were administered along with the Cigarette Purchase Task (CPT), Fagerström Test for Cigarette Dependence (FTCD), and The Questionnaire of Smoking Urges (QSU-brief). Both single-item breakpoint versions were significantly correlated with CPT-derived demand measures loaded on the persistence factor (i.e., elasticity of demand, breakpoint, Pmax, and Omax), but not with those loaded on the amplitude factor (i.e., intensity of demand). In addition, both single-item measures were associated with metrics of tobacco dependence (e.g., FTCD, QSU) with effect sizes that are similar to the ones found between CPT-derived breakpoint and those same metrics. These findings suggest that the single-item breakpoint measure is a viable method for measuring demand that may provide a useful and efficient tool to capture crucial and distinct aspects of smoking. In addition, the breakpoint measures may help increase the utility of behavioral demand measures in novel research and clinical settings. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

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.

Understanding alcohol motivation using the alcohol purchase task: A methodological systematic review.

BACKGROUND: The Alcohol Purchase Task (APT) is a behavioral economic assessment of alcohol demand (i.e., motivation for consumption during escalating levels of response cost) using simulated marketplace survey techniques. While the APT is often used and widely cited, to date, there has yet to be a systematic review elucidating the variability in administering and analyzing the APT. The purpose of the current paper is to address this knowledge gap in the literature by cataloging the various purchase task methodologies and providing recommendations and future areas of inquiry. METHODS: The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methodology was utilized (Prospero: No. CRD42017072159). Searches through Google Scholar, PsychINFO, PubMed, and SpringerLink databases identified 47 empirical articles referencing the use of an APT and published through the year 2016. Articles were coded for demographic and procedural characteristics, structural characteristics of the APT itself, and characteristics of data analysis. RESULTS: Results indicate substantial variation within categories and suggest that there is no standard approach to administering the APT or analyzing the responses generated from it. The results underscore the need for researchers to report as much information as possible related to administration, instructions, price structuring, and analytical approach, as we found that many articles did not provide these details. CONCLUSION: Enhancing the transparency of APT methods and analyses in published reports will aid in reproducibility as well as future meta-analytic studies of alcohol demand that could lead to the development of best-practice recommendations for this procedure.