title: On the latent structure of problem gambling: a taxometric analysis.
abstract: OBJECTIVE
  To test whether problem gambling is a categorical or dimensional disorder on the basis of two problem gambling assessments. This distinction discriminates between two different conceptualizations of problem gambling: one that problem gambling is defined by its addictive properties, the other that it is a continuum of harm.
  
  
  METHODS
  Using The British Gambling Prevalence Survey 2010, a nationally representative sample of the United Kingdom conducted by the National Centre for Social Research, five different taxometric analyses were carried out on cases from two problem gambling screens: the Problem Gambling Severity Index (PGSI) and a measure derived from the DSM-IV Pathological Gambling criteria. Two further analyses were conducted on the total scores for these measures.
  
  
  RESULTS
  There was strong evidence that both scales were measuring a categorical construct. Fit indices consistently supported a categorical interpretation [comparison curve fit index (CCFI) > 0.6]. The PGSI analysis indicated the presence of a taxon (CCFIs = 0.633, 0.756). The analysis conducted on the adapted DSM-IV criteria indicated stronger quantitative support for a taxon (CCFIs = 0.717, 0.811 and 0.756) but items probing a loss of control were inconsistent. The taxometric analyses of both scales support a categorical interpretation (CCFIs = 0.628, 0.567), but extreme caution should be used due to high nuisance covariance.
  
  
  CONCLUSIONS
  Two problem gambling screens (the Problem Gambling Severity Index and a measure derived from the DSM-IV Pathological Gambling criteria) appear to measure a categorical construct that taps into a categorical, loss of control model of problem gambling. There is some evidence that the two screens measure different aspects of an addiction construct.
authors.affiliation: School of Psychology, University of Nottingham, Nottingham, UK.
authors.forename: Richard J E
authors.initials: RJ
authors.lastname: James
authors.forename: Claire
authors.initials: C
authors.lastname: O'Malley
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Tunney
mesh_terms: D016739:Behavior, Addictive / Q000145:classification* / Q000523:psychology; D003430:Cross-Sectional Studies; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005715:Gambling / Q000145:classification* / Q000523:psychology; D006801:Humans; D011594:Psychometrics / Q000379:methods*; D006113:United Kingdom
keywords: Categorical; DSM; dimensional; gambling; nosology; problem gambling; survey; taxometric analysis