title: Reliability of a patient-reported outcome measure in schizophrenia: Results from back-to-back self-ratings.
abstract: This study aimed to assess patient's capacity to perform a patient-reported outcome (PRO) measure (i.e., a self-rating scale) and examine its relationship with clinical characteristics including cognition. Fifty patients with schizophrenia were asked to rate the Subjective Well-being under Neuroleptics scale - Short form (SWNS) twice; the second rating was started immediately after they completed the first to minimize the gap between ratings. At the same time, the Positive and Negative Symptoms Scale (PANSS) and Brief Neurocognitive Assessment (BNA) were administered. The correlations between the two ratings for the SWNS total and each item scores were high (rs=0.94 and rs=0.60-0.84, respectively); however, for 16 (80%) of 20 items, 5 or more patients (i.e., ≥10%) demonstrated a>1 point score difference. There was no significant correlation between the SWNS total score difference and any clinical characteristics including age, education duration, illness duration, antipsychotic dose, psychopathology, and cognition. In contrast, the number of items with a>1 point score difference was significantly correlated with disorganized symptoms and overall severity (rs=0.29 for both), as well as working memory and global cognition (rs=-0.41 and rs=-0.40, respectively). These findings suggest that PROs should be interpreted with caution in patients with schizophrenia with prominent disorganization and cognitive impairment.
authors.affiliation: Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, Canada; Department of Psychiatry, University of Toronto, Toronto, Canada; Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan. Electronic address: hirotak@dk9.so-net.ne.jp.
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Takeuchi
authors.affiliation: Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, Canada; Institute of Medical Science, University of Toronto, Toronto, Canada.
authors.forename: Gagan
authors.initials: G
authors.lastname: Fervaha
authors.affiliation: Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, Canada; Department of Psychiatry, University of Toronto, Toronto, Canada; Institute of Medical Science, University of Toronto, Toronto, Canada.
authors.forename: Gary
authors.initials: G
authors.lastname: Remington
mesh_terms: D000328:Adult; D000368:Aged; D014150:Antipsychotic Agents / Q000627:therapeutic use; D003072:Cognition Disorders / Q000175:diagnosis / Q000188:drug therapy / Q000523:psychology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008875:Middle Aged; D000071066:Patient Reported Outcome Measures; D015203:Reproducibility of Results; D012559:Schizophrenia / Q000175:diagnosis* / Q000188:drug therapy; D012565:Schizophrenic Psychology; D057566:Self Report / Q000592:standards*
chemical_list: D014150:Antipsychotic Agents
keywords: Cognition; Patient-reported outcome measures; Reliability; Schizophrenia; Self-rating; Subjective well-being