Caffeine consumption, expectancies of caffeine-enhanced performance, and caffeinism symptoms among university...

The expectancies paradigm developed in alcohol research was used to study caffeine consumption and signs of caffeinism in two groups of college students. A survey questionnaire was developed to gather self-report data on expectations of caffeine-enhanced performance (EP-CAFF), level of beverage caffeine consumed daily, and DSM-111 caffeinism signs reportedly experienced after consumption of caffeinated beverages. A positive association between EP-CAFF and both caffeine consumption and caffeinism signs was predicted. In both initial (n = 527) and cross-validation (n = 270) samples, significant correlations between EP-CAFF scores and both caffeine consumption and caffeinism symptoms were found. A small, but statistically significant, relationship was also found between caffeinism symptoms and both alcohol consumption and cigarette smoking. Of the 797 subjects in the combined sample, 151 (18.9%) endorsed five or more DSM-III caffeinism signs. Subjects endorsing five or more signs of caffeinism scored higher on the EP-CAFF scale, and consumed more caffeine and alcohol in both studies and smoked more cigarettes in study one--but not in study two--than did subjects who endorsed fewer than five caffeinism signs. Results support the utility of extending the expectancies model of substance use motivation from alcohol to caffeine.