Applying behavioral theories of choice to substance use in a sample of psychiatric outpatients.

The current study tests the utility of the contextual view of reinforcement in predicting substance use among a sample of 34 psychiatric outpatients enrolled at a public psychiatric facility. Participants reported substance use, as well as the frequency and enjoyability of a variety of potential reinforcers, for the previous 30 days. A series of regression analyses revealed that a ratio of reinforcement from substance use relative to total reinforcement was more predictive of substance use days than was reinforcement for substance use taken alone. The results demonstrate importance of viewing behaviors within their broader environmental context and support predictions derived from the behavioral choice perspective. According to behavioral theories of choice, a preference for a given reinforcer arises within the context of other available reinforcers (Vuchinich & Tucker, 1996). Herrnstein's (1970) matching law, a mathematical account of choice behavior, provides foundation for the behavioral choice perspective by empirically documenting the importance of context. The theory and accompanying equations specify that a person's behavior is distributed across concurrently available options in proportion to the amount of reinforcement received for engaging in each behavior. Within this framework, the amount of reinforcement received for a behavior relative to other options is viewed as more predictive of choice behavior than the absolute amount of reinforcement received (McDowell, 1988). McDowell's review of the literature suggests the matching law can adequately describe human choice behavior in both controlled and natural environments. Vuchinich (1995) proposed that empirical research derived from behavioral theories, such