title: Relative and Absolute Reliabilities of the Conners' Continuous Performance Test II in Schizophrenia.
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.
  
  
  METHODS
  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.
authors: Department of Occupational Therapy, I-Shou University, Kaohsiung, Taiwan.
authors: Posen
authors: P
authors: Lee
authors: Department of Occupational Therapy, Asia University, Taichung, Taiwan.
authors: Hung-Yu
authors: HY
authors: Lin
authors: Department of Occupational Rehabilitation, Kai-Suan Psychiatric Hospital, Kaohsiung, Taiwan.
authors: Chin-Hsuan
authors: CH
authors: Liu
authors: School of Occupational Therapy, Chung Shan Medical University and Occupational Therapy Room, Chung Shan Medical University Hospital, Taichung, Taiwan.
authors: Wen-Shian
authors: WS
authors: Lu
authors: School of Occupational Therapy, College of Medicine, National Taiwan University, Taipei, Taiwan.|Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, Taipei, Taiwan.
authors: Ching-Lin
authors: CL
authors: Hsieh
keywords: Attention; Continuous performance test; Schizophrenia