Interrater reliability of the Structured Clinical Interview for the Positive and Negative Syndrome Scale for schizophrenia.

The Swedish version of the Positive and Negative Syndrome Scale for schizophrenia (PANSS) has been tested and construct validity, internal reliability and interrater reliability have been demonstrated to be quite satisfactory. However, the interrater reliability of the negative symptoms was unsatisfactory low. In this study, the Swedish version of the Structured Clinical Interview for the PANSS has been tested. The interrater reliability is increased as compared with the inter-rater reliability achieved by means of the PANSS. As concerns the positive scale, the intraclass coefficients increased to 0.98-0.99 with the SCID-PANSS. For the negative scale, the intraclass coefficients increased to 0.83-0.90 with the SCID-PANSS, and for the general scale the increase was to 0.95-0.98 with the SCID-PANSS. It was also demonstrated that the interrater reliability is higher for the positive and the negative factors derived from the PANSS than for the positive and the negative scales.