title: Converting positive and negative symptom scores between PANSS and SAPS/SANS.
abstract: The Scale for the Assessment of Positive Symptoms (SAPS), the Scale for the Assessment of Negative Symptoms (SANS), and the Positive and Negative Syndrome Scale for Schizophrenia (PANSS) are the most widely used schizophrenia symptom rating scales, but despite their co-existence for 25 years no easily usable between-scale conversion mechanism exists. The aim of this study was to provide equations for between-scale symptom rating conversions. Two-hundred-and-five schizophrenia patients [mean age±SD=39.5±11.6, 156 males] were assessed with the SANS, SAPS, and PANSS. Pearson's correlations between symptom scores from each of the scales were computed. Linear regression analyses, on data from 176 randomly selected patients, were performed to derive equations for converting ratings between the scales. Intraclass correlations, on data from the remaining 29 patients, not part of the regression analyses, were performed to determine rating conversion accuracy. Between-scale positive and negative symptom ratings were highly correlated. Intraclass correlations between the original positive and negative symptom ratings and those obtained via conversion of alternative ratings using the conversion equations were moderate to high (ICCs=0.65 to 0.91). Regression-based equations may be useful for conversion between schizophrenia symptom severity as measured by the SANS/SAPS and PANSS, though additional validation is warranted. This study's conversion equations, implemented at http:/converteasy.org, may aid in the comparison of medication efficacy studies, in meta- and mega-analyses examining symptoms as moderator variables, and in retrospective combination of symptom data in multi-center data sharing projects that need to pool symptom rating data when such data are obtained using different scales.
authors: Department of Psychiatry and Human Behavior, University of California, Irvine, Irvine, CA 92617, United States.
authors: Theo G M
authors: TG
authors: van Erp
authors: Department of Psychiatry and Human Behavior, University of California, Irvine, Irvine, CA 92617, United States.
authors: Adrian
authors: A
authors: Preda
authors: Department of Psychiatry and Human Behavior, University of California, Irvine, Irvine, CA 92617, United States.
authors: Dana
authors: D
authors: Nguyen
authors: Department of Psychiatry and Human Behavior, University of California, Irvine, Irvine, CA 92617, United States.
authors: Lawrence
authors: L
authors: Faziola
authors: Mind Research Network, Albuquerque, NM 87106, United States; Departments of Psychiatry & Neuroscience, University of New Mexico, Albuquerque, NM 87131, United States.
authors: Jessica
authors: J
authors: Turner
authors: Departments of Psychiatry & Neuroscience, University of New Mexico, Albuquerque, NM 87131, United States.
authors: Juan
authors: J
authors: Bustillo
authors: Departments of Psychiatry and Psychology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, United States.
authors: Aysenil
authors: A
authors: Belger
authors: Department of Psychiatry, University of Minnesota, Minneapolis, MN 55454, United States.
authors: Kelvin O
authors: KO
authors: Lim
authors: Department of Psychology, University of California, Los Angeles, Los Angeles, CA 90095, United States.
authors: Sarah
authors: S
authors: McEwen
authors: Brain Imaging and Analysis Center, Duke University Medical Center, Durham, NC 27710, United States.
authors: James
authors: J
authors: Voyvodic
authors: Department of Psychiatry, University of California, San Francisco, San Francisco, CA 94143, United States; Mental Health Service, San Francisco Veterans Affairs Medical Center, San Francisco, CA, 94121, United States.
authors: Daniel H
authors: DH
authors: Mathalon
authors: Department of Psychiatry, University of California, San Francisco, San Francisco, CA 94143, United States; Mental Health Service, San Francisco Veterans Affairs Medical Center, San Francisco, CA, 94121, United States.
authors: Judith
authors: J
authors: Ford
authors: Department of Psychiatry and Human Behavior, University of California, Irvine, Irvine, CA 92617, United States.
authors: Steven G
authors: SG
authors: Potkin
authors: Department of Psychiatry and Human Behavior, University of California, Irvine, Irvine, CA 92617, United States.
authors: Fbirn
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011569:Psychiatric Status Rating Scales; D011594:Psychometrics; D012044:Regression Analysis; D015203:Reproducibility of Results; D012559:Schizophrenia / Q000150:complications* / Q000175:diagnosis*; D012565:Schizophrenic Psychology; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Conversion; Marder; Meta; Multi-center; Schizophrenia; Symptoms