A taxometric study of alcohol abuse and dependence in a general population sample: evidence of dimensional latent structure and implications for DSM-V.

AIMS: To explore, with the aid of taxometric analysis, whether alcohol abuse and alcohol dependence are each conceptualized most effectively as single latent dimensions or distinct latent categories.
DESIGN: Data were taken from a nationally representative cross-sectional epidemiological survey of psychiatric and substance use disorders.
SETTING: General population of Australia. PARTICIPANTS: A subsample of all respondents who had consumed at least 12 drinks in the year prior to the survey and who had consumed at least three drinks on at least one single day (n = 4920 of a possible 10,641). MEASUREMENTS: DSM-IV criteria for alcohol abuse and dependence were assessed with the Composite International Diagnostic Interview, version 2.1. Two independent taxometric procedures, MAXimum EIGenvalue (MAXEIG) and mean above minus below a cut (MAMBAC), together with analysis of simulated dimensional and categorical data sets, were carried out. Findings Consistent evidence was found for a single latent dimension underlying the symptoms of alcohol dependence. Less consistent evidence of dimensionality was found for the symptoms of alcohol abuse.
CONCLUSIONS: These findings support the growing consensus regarding the need for continuous measures of alcohol use disorders to complement the traditional categorical representations in upcoming versions of the major psychiatric classification systems.