title: Using the Schedules for Clinical Assessment in Neuropsychiatry (SCAN 2.1) as a diagnostic interview providing dimensional measures: cross-national findings on the psychometric properties of psychopathology scales.
abstract: BACKGROUND
  The Schedules for Clinical Assessment in Neuropsychiatry (SCAN) is a set of clinical assessment instruments developed under the auspices of WHO. In contrast to other structured diagnostic interviews, SCAN also provides possibilities for dimensional assessment of psychopathology. This paper reports cross-national findings on the psychometric properties of psychopathology scales derived from SCAN 2.1.
  
  
  METHODS
  Within a randomized controlled trial, SCAN 2.1 was used in Dresden (Germany), Michalovce (Slovak Republic), Prague (Czech Republic), and Wrocław (Poland). Forty-seven items from Part I of SCAN 2.1, identified as qualifying for constructing dimensional measures, were, on the one hand, grouped according to their allocation to five specific SCAN 2.1 sections. On the other hand, principal component analyses were used to group the items according to their statistical relationship. To estimate the reliability of the scales, Cronbach's alpha was computed. To assess factor similarity across sites, Tucker's congruence coefficients were calculated. To appraise concurrent validity, mean scale scores were compared across different diagnostic groups.
  
  
  RESULTS
  Reliability was qualified as moderate to substantial for all generated scales. Factor-solutions differed across sites. Differences in mean scores supported the assumption that the scales might possess, in addition to face validity, concurrent validity.
  
  
  CONCLUSIONS
  This is the first cross-national study on the psychometric properties of psychopathology scales derived from SCAN 2.1, and findings are very encouraging concerning its use as a dimensional measure. However, further studies are needed to substantiate implementation of the scales established.
authors.affiliation: Dresden University of Technology, Department of Psychiatry and Psychotherapy, Fetscherstr. 74, D-01307 Dresden, Germany. matthias.schuetzwohl@tu-dresden.de
authors.forename: Matthias
authors.initials: M
authors.lastname: Schützwohl
authors.forename: Thomas
authors.initials: T
authors.lastname: Kallert
authors.forename: Luisa
authors.initials: L
authors.lastname: Jurjanz
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D018153:Czech Republic / Q000453:epidemiology; D003710:Demography; D005163:Factor Analysis, Statistical; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D038801:International Classification of Diseases; D007406:Interview, Psychological; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D009462:Neurology / Q000379:methods*; D011044:Poland / Q000453:epidemiology; D011570:Psychiatry / Q000379:methods*; D011594:Psychometrics / Q000706:statistics & numerical data; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D018154:Slovakia / Q000453:epidemiology