title: Motivational typologies of drinkers: do enhancement and coping drinkers form two distinct groups?
abstract: OBJECTIVE
  This study used a person-centered approach to test whether drinking motive typologies could be identified.
  
  
  METHODS
  Longitudinal study of college students within the intensive multivariate prospective alcohol college-transitions (IMPACTS) data set.
  
  
  METHODS
  University campus in the United States.
  
  
  METHODS
  University students (baseline n reporting alcohol motives = 2158; baseline age = 18.60 years old).
  
  
  METHODS
  The drinking motives questionnaire-revised (DMQ-R).
  
  
  RESULTS
  Using Steinley & Brusco's cluster analysis approach [based on the theoretical ratio expected between the within sum of squares and the total sum of squares when the data are divided into two clusters when no cluster structure is present; the cut-off for the ratio is 0.25 for uniform (multivariate uniform) distributions and 0.36 for normal (multivariate normal) distributions], we examined whether there was evidence for distinct clusters of individuals that differed on their overall level of motives to drink. We tested the fit of a one-group (cluster) solution compared to multi-cluster solutions. Both cross-sectionally and prospectively, the data could not be partitioned into two or more clusters [regardless of whether the cut-off assuming a multivariate uniform distribution (i.e. 0.25) or the more liberal multivariate normal distribution (i.e., 0.36) was used]. These findings showed that enhancement and coping drinkers do not form two distinct groups but, rather, these motives exist on a continuum such that individuals who are high in one internal motive tend to be high in the other motive.
  
  
  CONCLUSIONS
  Coping and enhancement drinkers do not form two distinct groups. Variable-centered approaches to drinking motives may be a better alternative to classifying all drinkers as either enhancement or coping drinkers for both clinical and research endeavors.
authors.affiliation: University of Missouri-Columbia and the Midwest Alcoholism Research Center, Columbia, MO 65201, USA. akl9af@mail.missouri.edu
authors.forename: Andrew K
authors.initials: AK
authors.lastname: Littlefield
authors.forename: Alvaro
authors.initials: A
authors.lastname: Vergés
authors.forename: Jenny M
authors.initials: JM
authors.lastname: Rosinski
authors.forename: Douglas
authors.initials: D
authors.lastname: Steinley
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Sher
mesh_terms: D000223:Adaptation, Psychological; D000293:Adolescent; D000428:Alcohol Drinking / Q000523:psychology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009042:Motivation; D013334:Students / Q000523:psychology; D011795:Surveys and Questionnaires; D014481:United States