Reliability, validity and treatment sensitivity of the Schizophrenia Cognition Rating Scale

Abstract

Cognitive functioning can be assessed with performance-based assessments such as neuropsychological tests and with interview-based assessments. Both assessment methods have the potential to assess whether treatments for schizophrenia improve clinically relevant aspects of cognitive impairment. However, little is known about the reliability, validity and treatment responsiveness of interview-based measures, especially in the context of clinical trials. Data from two studies were utilized to assess these features of the Schizophrenia Cognition Rating Scale (SCoRS). One of the studies was a validation study involving 79 patients with schizophrenia assessed at 3 academic research centers in the US. The other study was a 32-site clinical trial conducted in the US and Europe comparing the effects of encenicline, an alpha-7 nicotine agonist, to placebo in 319 patients with schizophrenia. The SCoRS interviewer ratings demonstrated excellent test-retest reliability in several different circumstances, including those that did not involve treatment (ICC> 0.90), and during treatment (ICC>0.80). SCoRS interviewer ratings were related to cognitive performance as measured by the MCCB (r=-0.35), and demonstrated significant sensitivity to treatment with encenicline compared to placebo (P<.001). These data suggest that the SCoRS has potential as a clinically relevant measure in clinical trials aiming to improve cognition in schizophrenia, and may be useful for clinical practice. The weaknesses of the SCoRS include its reliance on informant information, which is not available for some patients, and reduced validity when patient's self-report is the sole information source.

Keywords: Assessment; Cognition; Cognitive impairment; SCoRS; Schizophrenia; Treatment response.

Conflict of interest statement

CONFLICT OF INTEREST

Dr. Richard Keefe currently or in the past 3 years has received investigator-initiated research funding support from the Department of Veteran’s Affair, Feinstein Institute for Medical Research, GlaxoSmithKline, National Institute of Mental Health, Novartis, Psychogenics, Research Foundation for Mental Hygiene, Inc., and the Singapore National Medical Research Council. He currently or in the past 3 years has received honoraria, served as a consultant, or advisory board member for Abbvie, Akebia, Amgen, Astellas, Asubio, AviNeuro/ChemRar, BiolineRx, Biogen Idec, Biomarin, Boehringer-Ingelheim, Eli Lilly, EnVivo, GW Pharmaceuticals, Helicon, Lundbeck, Merck, Minerva Neurosciences, Inc., Mitsubishi, Novartis, Otsuka, Pfizer, Roche, Shire, Sunovion, Takeda, Targacept. Dr. Keefe receives royalties from the BACS testing battery, the MATRICS Battery (BACS Symbol Coding) and the Virtual Reality Functional Capacity Assessment Tool (VRFCAT). He is also a shareholder in NeuroCog Trials, Inc. and Sengenix.

Meera Narasimhan reports having received grant or research support over the last 3 years from the National Insitute of Mental Health, the National Insitute of Drug Abuse, the National Institues of Alcohol Abuse and Alcoholism, the National Institutes of Health, Astra Zeneca, Eli Lilly, Janssen Pharmaceutica, Forest Labs, and Pfizer.

Dana Hilt and Nancy Dgetluck are full time employees of FORUM Pharmaceuticals.

Vicki Davis, Nathan Spagnola, and Stacy Ruse are full time employees of NeuroCog Trials, Inc.

Dr. Patterson has no conflicts of interest to disclose.

Dr. Harvey reports having received consulting fees for Abbvie, Boeheringer-Ingelheim, En Vivo, Genentech, Otsuka America, Sunovion Pharma, and Takeda Pharma. Dr. Harvey receives royalties from the Brief Assessment of Cognition in Affective Disorders (BAC-A) and the Brief Assessment of Cognition in Schizophrenia (BACS).

Copyright © 2014 Elsevier B.V. and ECNP. All rights reserved.

Figures

Figure 1

Pearson Correlations between SCoRS items and MCCB Composite T-Score at Baseline from Patient and Interviewer Ratings