Background: We sought to develop a series of assessment measures of psychiatric spectrum conditions associated with major DSM-IV mood and anxiety disorders that might capture the true phenotypes underlying these disorders. The specific objective of this report was to describe the methods we employed to create instruments that could cross linguistic and national boundaries and to evaluate the comparability of results obtained when one of these instruments, the Structured Clinical Interview for Panic-Agoraphobic Spectrum (SCI-PAS), was administered in the United States and in Italy.
Method: After developing, in parallel, the English and the Italian versions of the SCI-PAS, identical protocols were conducted in patients and control samples at the University of Pittsburgh and the University of Pisa to examine the reliability and validity of the interview.
Results: Total and domain scores on the SCI-PAS were strikingly similar in the US and Italian patient groups and in controls. In addition, similarly high levels of inter-rater and test-retest reliability were found at the two sites. Finally, virtually identical patterns of relationships were found between the domains of the SCI-PAS and established measures of the same constructs.
Conclusions: The SCI-PAS displays similar reliability and validity properties in the two versions. This suggests that the instrument taps a phenotype that is consistent in American and Italian patient and control populations.