Today, there are numerous versions of the continuous performance test (CPT) used in clinical and research settings. Although CPTs may constitute a similar group of tasks with a common paradigm, they are very different in the parameters they measure (Conners, 1995). To learn more about the effects of different CPT versions as well as the numerous scoring indices, two very different CPTs, the Conners’ Continuous Performance Test-Second Edition (CCPT-II) and the Gordon Diagnostic System (GDS), were compared with a population of children and adolescents exhibiting ADHD and normal controls. Major findings were as follows: (a) the CCPT-II and GDS measures were not able to separate children with ADHD from normal controls; (b) individual variables from neither the CCPT-II nor the GDS were able to adequately differentiate children with ADHD and normal controls; and (c) score profiles obtained from the overall group of children and adolescents did not successfully separate the ADHD group from normal controls using the CCPT-II and GDS.

Two continuous performance tests were administered to normal adult subjects. The mode of presentation (visual or auditory) and the type of task (vigilance or distractibility) were varied, and their effects on performance measured. Data were collected on eighty-two subjects, and results indicated that auditory presentation of stimuli increased the difficulty of both tasks. Results also suggest that the distractibility task administered in either mode was more difficult than the vigilance task. Intercorrelations among the four continuous performance tasks are provided. Normative data are presented on all four tasks administered. A measure of symptoms of attention-deficit disorder in adults, the Adult Behavior Checklist, was found to correlate significantly with another measure of pathology, the SCL-90-R.