A Reliable and Valid Assessment of Sustained Attention for Patients With Schizophrenia: The Computerized Digit Vigilance Test.

Objective: The purposes of this study were to examine the test-retest reliability, concurrent validity, and ecological validity of the Computerized Digit Vigilance Test (C-DVT) in patients with schizophrenia.

Method: Each participant was assessed four times, with 1-week intervals. In each assessment, the participants completed both the C-DVT and the original DVT. The participants were also assessed using the Lawton Instrumental Activities of Daily Living Scale (LIADL) and the Personal and Social Performance Scale (PSP).

Results: Forty-nine participants were recruited in this study. The results showed that the test-retest agreement of the C-DVT was good-to-excellent (intraclass correlation coefficient = 0.71-0.89). The random measurement errors of the C-DVT were acceptable (percentages of minimal detectable change = 12.9%-24.1%). The practice effect of the C-DVT reached a plateau after three assessments (effect size <0.20). The concurrent validity of the C-DVT was good (r = .75-.79 with DVT) when we controlled for the randomized administration order of the two tests. The ecological validity of the C-DVT was good (r = -.44 with the LIADL; r = -.45 with the PSP).

Conclusions: The C-DVT had acceptable test-retest reliability, sound concurrent validity, and sound ecological validity in patients with schizophrenia. These findings indicate that the C-DVT has the potential to be a reliable and valid test of sustained attention in patients with schizophrenia.