This is a small study (n=46 college students) that certainly needs replication on a larger scale, with a more demographically diverse sample, before being taken as definitive. However, the finding that “… habit (emphasis added) was a significant predictor of both amount and proportion of alcohol consumed…[and] was shown to effectively discriminate between…” intention and behavior is worth thinking about.  It suggests that even if prevention programs are successful in changing intentions, established habits might diminish the effectiveness of the intervention in changing behavior.

Citation:

Albery, I. P., Collins, I., Moss, A. C., Frings, D., & Spada, M. M. (2014). Habit Predicts In-The-Moment Alcohol Consumption. Addictive Behaviors.

Abstract:

The objective of this study was to examine whether habit predicts in-the-moment behavioural intention (amount of alcohol poured) and behavioural enactment (amount and proportion of alcohol consumed) controlling for craving and positive alcohol expectancies. Forty-six college students, who defined themselves as social drinkers, were tested individually in a laboratory setting. After completing a measure of craving they were given a bottle of non-alcoholic beer and a cup, asked to pour a drink, and then drink as much as they liked. They were not informed that the beer was non-alcoholic. They were subsequently asked to complete measures of alcohol use and misuse, positive alcohol expectancies and habit. Results showed that positive alcohol expectancies were positively and significantly associated with amount of alcohol poured and amount and proportion of alcohol consumed. Habit was positively and significantly associated with amount and proportion of alcohol consumed but not with the amount of alcohol poured. Hierarchical regression analyses revealed that only habit was a significant predictor of both amount and proportion of alcohol consumed. Even though measures of intention (amount of alcohol poured) and behaviour (amount and proportion of alcohol consumed) were positively correlated, habit was shown to effectively discriminate between these measures. These findings suggest that habit predicts in-the-moment behavioural enactment in terms of amount and proportion of alcohol consumed.

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