The Computerized Test of Information Processing (CTIP) offers an alternative to the PASAT for assessing cognitive processing speed in individuals with multiple sclerosis.

OBJECTIVE: To compare the ability of the Computerized Test of Information Processing (CTIP) to detect impaired cognitive processing speed in patients with multiple sclerosis (MS) with a traditional 3.0 second Paced Auditory Serial Addition Test (PASAT) and the Adjusting-PASAT which allows for calculation of a speed score. BACKGROUND: A primary cognitive deficit in MS is an impaired ability to process information quickly. Unfortunately, relatively few clinical tests effectively measure information processing speed. Of these, the PASAT is generally acknowledged to be the most sensitive, but use of this test is constrained by several factors. METHODS: All tests were administered to 30 adults with relapsing-remitting MS and 30 control participants. RESULTS: A series of analysis of variances revealed MS participants performed significantly worse than controls on the CTIP and the 3.0 second PASAT, whereas no significant difference was observed for the Adjusting-PASAT. CONCLUSIONS: The results suggest the CTIP can detect deficits in the speed at which people with MS process information. Thus, the CTIP offers an alternative means to the 3.0 second PASAT included in the Multiple Sclerosis Functional Composite for assessing such impairment.

Reaction time: An alternative method for assessing the effects of multiple sclerosis on information processing speed.

The ability of a newly developed measure of information processing to detect deficits in cognitive functioning associated with multiple sclerosis (MS) was investigated. The Computerized Tests of Information Processing (CTIP; Tombaugh, T., & Rees, L. (1999). Computerized Tests of Information Processing (CTIP). Unpublished test. Ottawa, Ontario, Canada: Carleton University) was administered to 60 clinically definite MS patients and 60 healthy controls. MS patients responded significantly slower than controls on the reaction time tests composing the CTIP. Moreover, as the CTIP tests became more difficult (i.e. as processing demands increased), the difference between the performances of the two groups progressively increased. These results suggest the CTIP is sensitive to the cognitive deficits observed in MS and that this measure has the potential to serve as a viable alternative to traditional measures of information processing speed currently in use with MS patients.

The effects of mild and severe traumatic brain injury on speed of information processing as measured by the computerized tests of information processing (CTIP).

In spite of the fact that reaction time (RT) measures are sensitive to the effects of traumatic brain injury (TBI), few RT procedures have been developed for use in standard clinical evaluations. The computerized test of information processing (CTIP) [Tombaugh, T. N., & Rees, L. (2000). Manual for the computerized tests of information processing (CTIP). Ottawa, Ont.: Carleton University] was designed to measure the degree to which TBI decreases the speed at which information is processed. The CTIP consists of three computerized programs that progressively increase the amount of information that is processed. Results of the current study demonstrated that RT increased as the difficulty of the CTIP tests increased (known as the complexity effect), and as severity of injury increased (from mild to severe TBI). The current study also demonstrated the importance of selecting a non-biased measure of variability. Overall, findings suggest that the CTIP is an easy to administer and sensitive measure of information processing speed.

The effects of mild and severe traumatic brain injury on the auditory and visual versions of the Adjusting-Paced Serial Addition Test (Adjusting-PSAT).

Auditory and visual versions of the Adjusting-PSAT [Tombaugh, T. N. (1999). Administrative manual for the adjusting-paced serial addition test (Adjusting-PSAT). Ottawa, Ontario: Carleton University] were used to examine the effects of mild and severe traumatic brain injury (TBI) on information processing. The Adjusting-PSAT, a computerized modification of the original PASAT [Gronwall, D., & Sampson, H. (1974). The psychological effects of concussion. Auckland, New Zealand: Auckland University Press], systematically varied the inter-stimulus interval (ISI) by making the duration of the ISI contingent on the correctness of the response. This procedure permitted calculation of a temporal threshold measure that represented the fastest speed of digit presentation at which a person was able to process the information and provide the correct answer. Threshold values progressively declined as a function of the severity of TBI with visual thresholds significantly lower than auditory thresholds. The major importance of the current study is that the threshold measure offers a potentially more precise way of evaluating how TBI affects cognitive functioning than is achieved using the traditional PASAT and the number of correct responses. The Adjusting-PSAT offers the additional clinical advantages of eliminating the need to make a priori decisions about what ISI should be used in different clinical applications, and avoiding spuriously high levels of performance that occur when an "alternate answer" or chunking strategy is used. Unfortunately, the Adjusting-PSAT did not reduce the high level of frustration previously associated with the traditional PASAT.

A comprehensive review of the Paced Auditory Serial Addition Test (PASAT).

The Paced Auditory Serial Addition Test (PASAT) was developed to assess the effects of traumatic brain injury (TBI) on cognitive functioning. Subsequent research has shown that the PASAT has clinical utility in detecting impairments in cognitive processing in patients with a wide variety of neuropsychological syndromes. Gronwall and Sampson (1974) originally assumed the PASAT measured speed of information processing. However, the PASAT is now recognized as a measure of multiple functional domains because it requires the successful completion of a variety of cognitive functions, primarily those related to attention. While the PASAT has demonstrated good psychometric properties such as high levels of internal consistency and test-retest reliability, several issues should be considered when administering and interpreting this test. For example, test-retest scores show that the PASAT is extremely susceptible to practice effects. The PASAT is also negatively affected by increasing age, decreasing IQ, and low math ability. Administration of the PASAT creates an undue amount of anxiety and frustration in participants which affects their performance on this and other neuropsychological tests, and may subsequently increase their reluctance to return for follow up testing. Demands for rapid responding place individuals with speech or language impairment at a distinct disadvantage, as it does for those who naturally speak slowly for cultural or geographic reasons. In conclusion, the PASAT represents a reliable test that has legitimate but restricted clinical applications. A low score on the PASAT may not necessarily indicate or confirm the presence of neurological pathology. The PASAT is a highly sensitive, non-specific test and as such, care must be taken to identify the reasons underlying any low score before interpreting it as clinically significant.

Detecting simulation of attention deficits using reaction time tests.

The current study examined if a newly developed series of reaction time tests, the Computerized Tests of Information Processing (CTIP), were sensitive to simulation of attention deficits commonly caused by traumatic brain injury (TBI). The CTIP consists of three reaction time tests: Simple RT, Choice RT, and Semantic Search RT. These tests were administered to four groups: Control, Simulator, Mild TBI, and Severe TBI. Individuals attempting to simulate attention deficits produced longer reaction time scores, made more incorrect responses, and exhibited greater variability than cognitively-intact individuals and those with TBI. Sensitivity and specificity values were comparable or exceeded those obtained on the Test of Memory Malingering. As such, the CTIP offers considerable promise of serving as a viable malingering test that uses a distinctively different paradigm than the two-item, forced-choice procedure employed by traditional symptom validity tests.

Test-retest reliable coefficients and 5-year change scores for the MMSE and 3MS.

The present study explored several different procedures for determining the amount of change that occurred on the Mini-Mental State Exam [MMSE; Folstein, M. F., Folstein, S. E., & McHugh, P. R. (1975). "Mini-Mental State": A practical method for grading the cognitive state of patients for the clinician. Journal of Psychiatric Research, 12, 189-198] and Modified Mini-Mental State Exam [3MS; Teng, E. L., & Chui, H. C. (1987). The Modified Mini-Mental State (3MS) examination. Journal of Clinical Psychiatry, 48, 314-318] over short and extended test-retest intervals. The test-retest scores were drawn from a selected sample of elderly individuals who participated in the Canadian Study of Health and Aging [Canadian Study of Health and Aging. (1994). The Canadian study of health and aging: Study methods and prevalence of dementia. Canadian Medical Association Journal, 150, 899-913] and were tested on two occasions (CSHA-1 and CSHA-2) separated by 5 years. On each occasion the MMSE and 3MS were administered twice at approximately 3-month intervals. Thus, the mental status tests were administered four times: times 1 and 2 at CSHA-1 and times 3 and 4 at CSHA-2. Mean difference scores and percent of baseline scores showed relatively small group changes over both short and long test-retest intervals for the MMSE and the 3MS. A reliable change index based on a linear regression model controlled for practice effects, psychometric errors due to low reliability, regression to the mean, and accounted for the effects of various demographic variables. Consequently, this reliable change index provided a better estimate of the amount of change that occurred for individual participants than did the mean Retest-Test 1 difference, percent of baseline change, or a reliable change index based on a Retest-Test 1 difference score. Normative data for the change scores are provided.

Trail Making Test A and B: normative data stratified by age and education.

Normative data for the Trail Making Test (TMT) A and B are presented for 911 community-dwelling individuals aged 18-89 years. Performance on the TMT decreased with increasing age and lower levels of education. Based on these results, the norms were stratified for both age (11 groups) and education (2 levels). The current norms represent a more comprehensive set of norms than previously available and will increase the ability of neuropsychologists to determine more precisely the degree to which scores on the TMT reflect impaired performance for varying ages and education.

Free-recall, cued-recall and recognition procedures with three verbal memory tests: Normative data from age 20 to 79.

New versions of three verbal learning tests (paragraph learning, list learning, and word-pair learning) were normed on 420 subjects, aged 20 to 79. These tasks used multiple acquisition trials, employed a delayed retention trial, incorporated the Buschke Selective Reminding procedure and utilized a continuum of free-recall, cued-recall, and recognition tasks. Norms are presented for six, 10-year age groups equated for intellectual level and gender. Normative groups also were screened for depression, dementia, and psychiatric illness. Results showed that all three tasks were highly reliable, demonstrated promising construct validity, and appeared to be measuring the same underlying cognitive function. Basic interpretative stategies for use with clinical data are proposed.