(PS1-4) Alcohol Reinforcement Value Predicts Intervention Response Through In-session Language

Objective: Alcohol reinforcement value (ARR, [i.e., a ratio of frequency and enjoyment of engaging in activities with versus without alcohol]) and alcohol use outcomes are associated, but the precise relationships remain unclear, including potential mechanisms of change explaining such relationships. This study examined how ARR is related to typical weekly drinking quantity and alcohol-related problems one-month post-intervention and whether in-session client language helps explain these relationships.

Method: Client language during brief motivational intervention (BMI) sessions from 351 college students (62.7% female, M_age=18.8 years) reporting past month risky alcohol use was coded for motivational valance (approach [+], neutral [=], or avoid [-]) and behavioral content (alcohol [ALC] vs. competitive reinforcers of alcohol [ALT]) using a novel coding system integrating principles of behavioral economics and motivational interviewing. ALT+ and ALC+ were computed as proportions of all codes in relevant domain. Alcohol reinforcement value was calculated as total reinforcement ratio (ARR) based on preintervention assessment and in accordance with computation recommendations by Hallgren et al. (2016). Parallel mediation analysis was used to examine whether ALT+ and ALC+ mediate the relationship between ARR and alcohol outcomes (i.e., drinking and problems).

Results: A significant indirect effect emerged, suggesting ALT+ mediates the relationship between ARR and problems at follow up (b = -.025, CI[-.0607, -.0004]). The indirect effect of ALC+ was not significant. After accounting for the indirect paths through ALT+ and ALC+, ARR did not directly predict problems at follow up. As with alcohol problems, ARR did not directly predict drinking at follow up nor indirectly through ALC+; however, analyses revealed a significant indirect effect (b = -.063, CI[-.1504, -.0025]) suggesting ALT+ mediates the relationship between ARR and drinking.

Conclusion: Through examination of causal mechanisms, these findings highlight the utility of differentially evoking language related to behavioral economics-oriented alternative reinforcers to alcohol during BMI. Future clinical training programs might consider developing interventions specifically targeting these in-session mechanisms of change for risky drinking, for example emphasizing content designed to increase the value of academics or physical activity.