Item response analysis of the Positive and Negative Syndrome Scale.

ABSTRACT:

Background

Statistical models based on item response theory were used to examine (a) the performance of individual Positive and Negative Syndrome Scale (PANSS) items and their options, (b) the effectiveness of various subscales to discriminate among individual differences in symptom severity, and (c) the appropriateness of cutoff scores recently recommended by Andreasen and her colleagues (2005) to establish symptom remission.

Methods

Option characteristic curves were estimated using a nonparametric item response model to examine the probability of endorsing each of 7 options within each of 30 PANSS items as a function of standardized, overall symptom severity. Our data were baseline PANSS scores from 9205 patients with schizophrenia or schizoaffective disorder who were enro

SUBMITTER: Santor DA 

PROVIDER: S-EPMC2211479 | biostudies-literature | 2007 Nov

REPOSITORIES: biostudies-literature