title: Validation of the cocaine versions of the Obsessive Compulsive Drug Use Scale and the Desires for Drug Questionnaire.
abstract: BACKGROUND
  The Obsessive Compulsive Drug Use Scale (OCDUS) and the Desires for Drug Questionnaire (DDQ) are two frequently used drug craving questionnaires. Although both heroin and cocaine versions of the questionnaires exist, only the heroin versions have been psychometrically evaluated. The present study was conducted to evaluate the psychometric qualities of the cocaine versions of the OCDUS (OCDUS-C) and DDQ (DDQ-C).
  
  
  METHODS
  Cocaine-dependent inpatients (n = 101) completed both scales as well as a Visual Analogue Craving Scale (VACS), an alternative, one-item index for assessing momentary craving. We examined the reliability (internal consistency), construct validity (factor structure), and concurrent validity (correlations among both questionnaires, the VACS, and indicators of severity of dependence). A subsample also completed the OCDUS-C and DDQ-C for a second time, one week after the initial administration to obtain a preliminary investigation of the test-retest reliability.
  
  
  RESULTS
  In general, both questionnaires displayed good internal consistency, test-retest reliability, and concurrent validity. Further, the construct validity of both the DDQ and OCDUS was demonstrated by means of confirmatory factor analyses showing the expected three-factor models.
  
  
  CONCLUSIONS
  Our results indicate that the OCDUS and DDQ for cocaine are both easy to administer and reliable instruments to assist the clinical practitioner or researcher to measure craving in cocaine dependent subjects. Moreover, the factor structure for the cocaine versions were similar to the heroin versions, indicating the OCDUS and the DDQ can be reliably used to measure craving for both substances, enabling a direct comparison between heroin and cocaine craving.
authors.affiliation: Institute of Psychology, Erasmus University Rotterdam , Rotterdam, the Netherlands .
authors.forename: Marien
authors.initials: M
authors.lastname: Lievaart
authors.forename: Fatos
authors.initials: F
authors.lastname: Erciyes
authors.forename: Frederik M
authors.initials: FM
authors.lastname: van der Veen
authors.forename: Ben J M
authors.initials: BJ
authors.lastname: van de Wetering
authors.forename: Peter
authors.initials: P
authors.lastname: Muris
authors.forename: Ingmar H A
authors.initials: IH
authors.lastname: Franken
mesh_terms: D000328:Adult; D000368:Aged; D019970:Cocaine-Related Disorders / Q000175:diagnosis* / Q000523:psychology; D003192:Compulsive Behavior / Q000175:diagnosis* / Q000523:psychology; D066249:Craving; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009770:Obsessive Behavior / Q000175:diagnosis* / Q000523:psychology; D011594:Psychometrics; D015203:Reproducibility of Results; D019966:Substance-Related Disorders / Q000175:diagnosis* / Q000523:psychology; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Cocaine dependency; DDQ; OCDUS; craving; drug craving questionnaires; psychometric properties