CALCAP® General Information

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The California Computerized Assessment Package is modeled after the Continuous Performance Task, a measure of sustained attention and reaction time. Subjects are asked to focus on a display field and respond only to specific visual stimuli.

The CALCAP program presents a broad range of stimulus materials on a standard MS-DOS computer, with exposure times precisely controlled by the computer program. Responses to the stimulus also are precisely measured and recorded and include:

These measures can be used to assess slowed cognition, focused and divided attention, sustained attention, and rapid visual scanning. It is ideal for longitudinal assessment of cognitive changes due to disease, medications, and cognitive rehabilitation.

The CALCAP test battery is currently being used to study changes in reaction time and speed of information processing in multiple sclerosis, hyperbaric nitrogen narcosis, HIV infection, dementia, drug abuse and traumatic brain injury.


The California Computerized Assessment Package (CALCAP) allows you to perform standardized assessments of reaction time and speed of information processing.

Computerized assessment techniques facilitate the application of technology and methods developed in experimental cognitive laboratories to the problems of applied clinical assessment. There are several advantages to this approach.

The standard CalCAP task consists of a series of ten fully normed Simple and Choice reaction time measures administered by computer. The tasks are designed to be self-explanatory and need only minimal supervision by the examiner. The complete procedure takes approximately 20-25 minutes for administration and scoring. The abbreviated version lasts 8-10 minutes and also includes comprehensive normative data. Stimulus materials are available in English, Spanish, Norwegian and Danish.

The individual reaction time measures are designed to assess a number of cognitive domains, including speed of processing (reaction time), language skills, rapid visual scanning, form discrimination, recognition memory, and divided attention.

The computer scores each task using age- and education-specific norms. Normative data are derived from over 1000 men and women ranging in age from 17 to 90. Additional norms are available for grade school children and for up to 6 repeated testings.

In addition to reaction time measures, level of performance on each task is assessed by evaluating the numbers of "Hits" and "False Positives." Signal detection theory provides measures of the subject's ability to discriminate between the true signal and distractor items (d') and of the degree to which the subject deviates from the optimal likelihood ratio (beta).


For more information, contact Eric Miller at emiller@calcaprt.com

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