Psychometric properties of the Italian version of the SCL-90-R: a study on a large community sample.

We present the factor structure and psychometric properties of the Italian version of the SCL-90-R based on a large sample of the Italian population. The sample (N=3631) included high-school and university students and adults from the community (age range=13-70 yrs; 39.2% males). Principal component analysis (PCA) supported by parallel analysis, yielded eight components, partially overlapping those in the original version; no evidence of Psychoticism and Paranoid Ideation as separate subscales emerged. Twenty-one items were consecutively deleted, leading to a 69-item version of the scale. Internal coherence was good for all subscales (α values between 0.70 and 0.96). However, the eight-factor solution did not prove consistent when analyses were replicated after dividing the sample in subgroups according to gender and age. A second-order PCA yielded a single factor, supporting the adoption of the GSI as an index of general distress. A 69-item brief version of the scale has been empirically derived in this study, and can possibly be adopted as a screening measure for general distress in Italian adults and adolescents; however, caution should be exercised when interpreting the clinical profile due to the instability of factor structure.