A behavioral economic measure of demand for alcohol predicts brief intervention outcomes |
Article in Press, Corrected Proof
7 February 2007
James MacKillopa, E-mail: james_mackillop@brown.edu , and
James G. Murphya, b
aCenter for Alcohol and Addiction Studies, Brown University, Providence, RI, USA
bAuburn University, Auburn, AL, USA
Abstract
Considerable basic and clinical research supports a behavioral economic conceptualization of alcohol and drug dependence. One behavioral economic approach to assess motivation for a drug is the use of demand curves, or quantitative representations of drug consumption and drug-reinforced responding across a range of prices.
This study used a hypothetical alcohol purchase task to generate demand curves, and examined whether the resulting demand curve parameters predicted drinking outcomes following a brief intervention.
Participants were 51 college student drinkers (67% female; 94% Caucasian; drinks/week: M = 24.57, S.D. = 8.77) who completed a brief alcohol intervention.
Consistent with predictions, a number of demand curve indices significantly predicted post-intervention alcohol use and frequency of heavy drinking episodes, even after controlling for baseline drinking and other pertinent covariates.
Most prominently, Omax (i.e., maximum alcohol expenditure) and breakpoint (i.e., sensitivity of consumption to increasing price) predicted greater drinking at 6-month post-intervention follow-up.
These results indicate that a behavioral economic measure of alcohol demand may have utility in characterizing the malleability of alcohol consumption. Moreover, these results support the utility of translating experimental assays of reinforcement into clinical research.
