Relative and Absolute Reliabilities of the Conners' Continuous Performance Test II in Schizophrenia

Posen Lee; Hung-Yu Lin; Chin-Hsuan Liu; Wen-Shian Lu; Ching-Lin Hsieh

doi:10.1093/arclin/acw037

Relative and Absolute Reliabilities of the Conners' Continuous Performance Test II in Schizophrenia

Arch Clin Neuropsychol. 2016 Nov 22;31(7):769-779. doi: 10.1093/arclin/acw037.

Authors

Posen Lee¹, Hung-Yu Lin², Chin-Hsuan Liu³, Wen-Shian Lu⁴, Ching-Lin Hsieh^{5

6}

Affiliations

¹ Department of Occupational Therapy, I-Shou University, Kaohsiung, Taiwan.
² Department of Occupational Therapy, Asia University, Taichung, Taiwan.
³ Department of Occupational Rehabilitation, Kai-Suan Psychiatric Hospital, Kaohsiung, Taiwan.
⁴ School of Occupational Therapy, Chung Shan Medical University and Occupational Therapy Room, Chung Shan Medical University Hospital, Taichung, Taiwan.
⁵ School of Occupational Therapy, College of Medicine, National Taiwan University, Taipei, Taiwan.
⁶ Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, Taipei, Taiwan.

PMID: 27506236
DOI: 10.1093/arclin/acw037

Abstract

Objective: The Conners' Continuous Performance Test II (CCPT-II) is one of the most commonly used tests of sustained attention in schizophrenia. To manage and monitor sustained attention deficits in schizophrenia, clinicians have to reliably assess the degree of attention impairment. The purpose of our study was to determine the relative and absolute reliability of the CCPT-II in schizophrenia.

Method: The final sample was a total of 108 patients with schizophrenia. The primary measures in this study were the CCPT-II and the Clinical Global Impression-Severity (CGI-S). The CCPT-II was administered twice, 1 month apart, by a specially trained occupational therapist. We assessed two types of reliability: relative and absolute reliability. Relative reliability was determined with the intra-class correlation coefficient (ICC). Absolute reliability was quantified with standard error of measurement (SEM), minimal detectable change (MDC), and Bland-Altman's 95% limits of agreement (LOA).

Results: The ICCs for the five CCPT-II indexes (Omissions, Commissions, Hit RT, Hit RT Std Error, and Variability) ranged from 0.66 to 0.79. The MDCs (MDC%) of the five indices were 13.53 (156.78), 10.67 (47.85), 122.10 (34.16), 8.15 (106.82), and 25.81 (162.63), respectively.

Conclusions: According to the results, the CCPT-II has limited reliability in monitoring the sustained attention function of patients with schizophrenia. Our results can be used as a reference for the measurement error of CCPT-II to help clinicians and researchers determine the true change between successive assessments of patients with schizophrenia.

Keywords: Attention; Continuous performance test; Schizophrenia.