Self-fulfilling prophecies: Documentation of real-world daily alcohol expectancy effects on the experience of specific positive and negative alcohol-related consequences

Alcohol expectancies are consistently associated with alcohol use in cross-sectional and longitudinal studies. However, little research has examined whether alcohol expectancies on specific drinking occasions are associated with reported consequences on those days, particularly when controlling for the amount of alcohol consumed, thus differentiating the extent to which reported consequences may have resulted from alcohol or an "expectancy effect. " This study examined consequence-specific daily expectancy effects. College students (N = 342; mean age 19.7 [standard deviation (SD) = 1.25], 52.9% female) participated in a longitudinal measurement burst study. During four 2-week intervals, participants used mobile phones to respond to 3 surveys per day via automated telephone interviews. The results showed that on days when college students had higher-than-average expectancies for specific subjective positive consequences (e.g., feeling more relaxed, being in a better mood), they were more likely to report experiencing those same consequences as a result of their alcohol use that day, even after controlling for how much they actually drank on that day. The same held true for subjective interpersonal negative consequences (e.g., becoming aggressive, rude, or obnoxious; embarrassing oneself), but not for less subjective physical/cognitive negative consequences (e.g., having a hangover, vomiting, getting hurt/ injured, forgetting). The results suggest that one's expectations about the particular effects of alcohol tend to be self-fulfilling for subjective effects of alcohol even when they are not directly tied to the physiological effects of alcohol. The findings underscore the important role of alcohol expectancies, particularly the expectation of subjective positive social and tension-reduction/relaxation effects, in understanding problematic alcohol use.