[Validation of the Psychiatric Diagnostic Screening Questionnaire (PDSQ) in a Spanish sample of alcoholic patients].

Objective: This study evaluates the psychometric properties of the Psychiatric Diagnostic Screening Questionnaire (PDSQ) in alcohol-dependent Spanish population as a means of detecting psychiatric comorbidity.

Methods: The PDSQ (Zimmerman, 2001) is a self-administered questionnaire with 125 items which can be applied in just 15 minutes, enabling rapid and effective screening of the psychiatric disorders (Axis I) most commonly found among substance abusers. After linguistic adaptation (translation/back-translation) and verification of its content validity, the PDSQ was administered to 156 alcohol-dependent patients (DSM-IV criteria; women = 36%), treated consecutively in an alcohol-disorders treatment setting. Its psychometric properties (reliability and validity) were determined, applying the DSM-IV criteria as a "gold standard", by means of SCID interview.

Results: Using the original cut-off points, the PDSQ showed excellent internal reliability (Alfa = 0.68-0.96) and diagnostic validity, with mean sensitivity = 99.6% (range: 96.6%-100%), specificity = 69.5% (range: 51.9%- 94.6%) and NPV = 99.8% (range: 98.6%-100%). Diagnostic efficiency with the original cut-off points was 73.2%, rising to 91.6% using new cut-off points for certain scales, with a degree of agreement with DSM-IV criteria of Kappa = .303 -. 896.

Conclusions: The PDSQ is a reliable and valid instrument for detecting psychiatric comorbidity in alcoholic individuals. Its psychometric properties and the added value of self-administration and short application time make it a recommended instrument for use in routine clinical settings.