title: The effect of sampling, diagnostic criteria and assessment procedures on the observed prevalence of DSM-III-R personality disorders among treated alcoholics.
abstract: OBJECTIVE. In a recent review of empirical studies on the prevalence of DSM-III-R personality disorders among substance abusers, wide ranges of prevalence rates for overall Axis II, antisocial personality disorder (APD) and borderline personality disorder (BPD) were shown. Utilizing subsamples from within a single study population, the current report explores the effect of sampling, diagnostic criteria and assessment procedures on the observed prevalence of DSM-III-R personality disorders among treated alcoholics.
  
  
  METHODS
  Personality disorders were assessed with the Personality Diagnostic Questionnaire Revised (PDQR) at two times of measurement (Time 1 n = 459; Time 2 n = 90). In addition, APD was measured with the Composite International Diagnostic Interview (CIDI; n = 587). Finally, an unselected subgroup (n = 136) was interviewed with the International Personality Disorder Examination (IPDE).
  
  
  RESULTS
  There were few differences between inpatients or outpatients or between males and females. Using the IPDE, the exclusion of substance-related pathology did not affect the prevalence estimate. However, the prevalence rates according to the PDQR varied greatly across age groups. In a representative subsample (n = 109), the prevalence rates also varied greatly across assessment methods (PDQR, 52% vs IPDE, 31%). The prevalence estimate of APD according to the CIDI was related to setting, gender, age group and the applied time-frame.
  
  
  CONCLUSIONS
  These findings indicate the examined factors to be necessary qualifiers of prevalence estimates and, consequently, support the use of a multiple-criteria/multimethod assessment battery in research as well as in clinical work.
authors.affiliation: Amsterdam Institute for Addiction Research, University of Amsterdam, The Netherlands.
authors.forename: R
authors.initials: R
authors.lastname: Verheul
authors.forename: C
authors.initials: C
authors.lastname: Hartgers
authors.forename: W
authors.initials: W
authors.lastname: Van den Brink
authors.forename: M W
authors.initials: MW
authors.lastname: Koeter
mesh_terms: D000328:Adult; D000437:Alcoholism / Q000453:epidemiology / Q000523:psychology / Q000534:rehabilitation*; D000987:Antisocial Personality Disorder / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D015982:Bias; D001883:Borderline Personality Disorder / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010343:Patient Admission; D010554:Personality Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data*; D011594:Psychometrics; D015203:Reproducibility of Results; D016896:Treatment Outcome