According to the theory of planned behavior, behavioral intentions play an important part in predicting future behavior. Previous research suggests young adults may be likely to deviate from their intended drinking behavior over the course of a drinking occasion, typically by drinking more than planned. A new study examined drinking intentions for a given evening among young adults and explored the individual and situational factors that contribute to deviations from initial intentions. Participants were recruited between 9pm and 12am by a field research team over a one-month period in popular nightlife areas in two Swiss cities, Lausanne and Zurich. Inclusion criteria were being between 16 and 25 years of age, owning an Android smartphone, having consumed alcohol at least once in the past month, and having been out in the city at least twice in the past month. Participants (n = 241) were asked to install the Youth@Night app, which documents event-level nightlife behaviors using questionnaires, pictures, videos, GPS, accelerometers, and other sensors. Participants were asked to use this app to report the types of drinks they consumed and characteristics of the locations they attended for at least 10 Friday or Saturday nights (including nights when they did not go out or did not drink) over seven consecutive weeks. A baseline questionnaire assessed monthly frequency of going out, monthly frequency of ‘predrinking’ or ‘pregaming,’ and monthly alcohol consumption. Between 5pm and 8pm on weekend nights, the app prompted participants to report the number of drinks they planned to consume that night. From 8pm until the end of the night, participants were asked to report the number of friends who were present each time they had another drink and each type of location where they drank (i.e., bar, private place). The following morning, participants were prompted to report the number of drinks they consumed the previous night. Deviation from drinking intention was measured by subtracting the number of drinks a participant intended to consume from the number actually consumed. The analytic sample consisted of 757 drinking intention and total consumption questionnaires and 356 consumption before 8pm questionnaires. On average, each participant had 4.3 fully documented nights (SD = 3.1), with 6.1 questionnaires per night (SD = 2.2). The authors used a series of multilevel regression models to investigate individual- and night-level predictors of intentions and deviation from intentions, respectively. At the night level, results showed alcohol consumption occurred on 79% of weekend nights and drinking began before 8pm on 45.2% of nights, during which participants consumed about two drinks each. On average, men intended to drink 3.1 alcoholic drinks (with intention to binge drink on 27.6% of nights) and women 1.8 (with intention to binge drink on 18.6% of nights), but men reported actually drinking 4.6 drinks (binge drinking 43.6% of nights) and women 2.9 (binge drinking 31.2% of nights). Thus, male participants drank more than intended on 51.0% of occasions and women on 44.1% of occasions. At the individual level, results found month frequency of predrinking for both genders and monthly alcohol consumption for men predicted high drinking intentions. For men and women, lower drinking intentions were associated with higher deviation from intention, and vice-versa, at both levels. Drinking early in the night was associated with a +0.42 drink deviation from intention for men and a +1.37 drink deviation for women for each drink consumed over and above the person’s usual consumption before 8pm. The effects of the gender of friends with whom participants drank and the locations at which drinking occurred varied by gender.

Take away: Overall, participants drank more than intended on nearly half of all nights and binge drank twice as often as planned. At both individual and occasion levels, the frequency of predrinking and number of drinks consumed before 8pm were significantly associated with heavier-than-intended drinking.

Citation: Labhart F, Anderson KG & Kuntsche E (2017). The spirit is willing, but the flesh is weak: Why young people drink more than intended on weekend nights—an event-level study [published online ahead of print October 2 2017], Alcoholism: Clinical and Experimental Research doi: 10.1111/acer.13490