Center for the Study of Health & Risk Behaviors (CSHRB), School of Medicine, Department of Psychiatry and Behavioral Sciences, University of Washington.
Center for Alcohol and Addiction Studies, Department of Behavioral and Social Sciences, Brown University School of Public Health.
Exp Clin Psychopharmacol. 2023 Feb;31(1):238-247. doi: 10.1037/pha0000570. Epub 2022 May 19.
Cannabis demand (i.e., reinforcing value) can be assessed using a marijuana purchase task (MPT; assesses hypothetical purchasing of cannabis at escalating prices) and has been related to use frequency, problems, and cannabis use disorder symptoms in adults. Cannabis demand has yet to be studied in adolescents, which can inform prevention and intervention efforts to reduce cannabis-related risks. The present study sought to validate the MPT with a sample of late adolescent lifetime cannabis users. Participants aged 15-18 years old ( = 115, = 16.9, = 0.9) residing in a state with legalized cannabis use completed online assessments at baseline and 6-month follow-up. Convergent and divergent validity was examined, while principal component analysis was conducted to determine the factor structure and assess predictive validity. Three indices, (i.e., maximum expenditure on cannabis), breakpoint (i.e., price suppressing consumption to zero), and alpha (i.e., degree to which consumption decreases with increasing price) were all significantly associated with cannabis use, consequences, craving, and expenditures and significantly differentiated low-risk users and high-risk users as measured by the Cannabis Use Disorders Identification Test-Revised (CUDIT-R). A two-factor solution reflecting amplitude (intensity, alpha, ) and persistence (breakpoint, ) was observed. Both factors were associated with cannabis use and consequences in baseline regression models. At follow-up, persistence was associated with consequences; amplitude was not associated with either outcome. These findings provide initial evidence that the MPT is a valid measure for assessing cannabis demand among adolescents and can be used to understand mechanisms of adolescent cannabis use. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
大麻需求（即强化价值）可以通过大麻购买任务（MPT；评估在不断增加的价格下购买大麻的假设情况）来评估，并且与成年人的使用频率、问题和大麻使用障碍症状有关。大麻需求在青少年中尚未得到研究，这可以为预防和干预措施提供信息，以减少与大麻相关的风险。本研究旨在通过一生中有大麻使用史的青少年样本验证 MPT。年龄在 15-18 岁之间的参与者（=115，=16.9，=0.9）居住在大麻使用合法化的州，在基线和 6 个月随访时完成在线评估。研究检验了聚合效度和区分效度，同时进行了主成分分析以确定因子结构并评估预测效度。三个指标，即（即，用于大麻的最大支出）、断点（即，将消费价格抑制为零的价格）和（即，消费随价格增加而减少的程度）均与大麻使用、后果、渴望和支出显著相关，并且根据大麻使用障碍识别测试修订版（CUDIT-R）显著区分了低风险使用者和高风险使用者。观察到反映幅度（强度、）和持久性（断点、）的双因素解决方案。在基线回归模型中，这两个因素都与大麻使用和后果相关。在随访时，持久性与后果相关；幅度与任何结果均无关。这些发现初步证明 MPT 是评估青少年大麻需求的有效衡量标准，可用于了解青少年大麻使用的机制。（PsycInfo 数据库记录（c）2023 APA，保留所有权利）。
