title: Field assessment of BAC data to study late-night college drinking.
abstract: OBJECTIVE
  This field study of late-night college drinking sought to (1) test the ability of the 5+/4+ measure to screen for higher levels of intoxication and (2) examine the relation between estimated and actual blood alcohol concentration (BAC).
  
  
  METHODS
  During a 15-week spring semester, college students returning to their residence halls between 10:00 PM and 3:00 AM on Wednesday through Saturday nights were anonymously interviewed to collect BAC and self-report data (n = 1,020).
  
  
  RESULTS
  Although 70.9% had not been drinking on Wednesday nights, a majority of the intercepted students had been drinking on the other three nights. Mean BACs on these three nights were in a moderate range (48 to 51 mg/dl), but the 5+/4+ measure classified many students as heavy episodic drinkers at relatively low BACs. For example, 66.3% of those meeting the 5+/4+ criterion for the night had BACs < 100 mg/dl. Students with BACs ranging from 70 to 90 mg/dl exhibited the greatest accuracy in estimating their BAC; those with lower BACs tended to overestimate their level of intoxication; whereas those with higher BACs tended to underestimate it.
  
  
  CONCLUSIONS
  Field assessment of student intoxication is an important tool for examining research questions in college drinking. The 5+/4+ measure classifies many college students as heavy episodic drinkers, even though their intoxication level is below conventional thresholds used to define drunkenness. In addition, there is a discernible pattern of BAC estimation in the field that corresponds to intoxication level.
authors.affiliation: Health Promotion Program, 316 White Hall, Kent State University, Kent, Ohio 44242, USA. dthombs@kent.edu
authors.forename: Dennis L
authors.initials: DL
authors.lastname: Thombs
authors.forename: R Scott
authors.initials: RS
authors.lastname: Olds
authors.forename: Barbara M
authors.initials: BM
authors.lastname: Snyder
mesh_terms: D000428:Alcohol Drinking / Q000097:blood* / Q000453:epidemiology* / Q000523:psychology; D001944:Breath Tests; D005260:Female; D006801:Humans; D008297:Male; D012044:Regression Analysis; D015203:Reproducibility of Results; D013334:Students / Q000523:psychology / Q000706:statistics & numerical data*; D011795:Surveys and Questionnaires; D013997:Time Factors; D014495:Universities / Q000706:statistics & numerical data*