Potential of and problems with new measures of psychometric intelligence after traumatic brain injury.

Abstract

Examination of the concurrent and criterion validities of the General Ability Measure for Adults (GAMA) and the Wechsler Adult Intelligence Scale-Third Edition (WAIS-IH) in patients with traumatic brain injury (TBI). Study Design: Correlational methods and multivariate analyses of variance. Setting: Regional rehabilitation center. Participants: Prospective series of consecutive rehabilitation referrals, including 60 adults with TBI and no confounding premorbid histories. Main Outcome Measures: GAMA and WAIS-IH IQ and factor index scores were obtained within 1 year after injury and were compared with each other and with measures of injury severity. Results: GAMA and WAIS-III summary IQ scores demonstrated substantial covariance (supporting concurrent validity), but neither was sufficiently sensitive to injury severity. The WAIS-III Processing Speed (PS) index was the only measure that clearly demonstrated criterion validity. Conclusions: GAMA and WAIS-III summary IQ scores measure similar abilities but may not be sensitive to degree of injury severity in individuals with TBI. In contrast, the WAIS-III PS index appears to have promise in the evaluation of sequelae of TBI.

WAIS-III Processing Speed Index Scores After TBI: The Influence of Working Memory, Psychomotor Speed and Perceptual Processing

“…Since publication of the third edition of the Wechsler Adult Intelligence Scale (WAIS-III; Wechsler, 1997), the Processing Speed Index (PSI) has become a commonly used measure of central processing speed. The PSI tends to be lowered in clinical samples (The Psychological Corporation, 1997), and preliminary evidence suggests that it may be the most sensitive index score in terms of brain dysfunction (Donders, 1997;Hawkins, 1998;Martin, Donders, & Thompson, 2000). This index score is derived from a combination of performances on the Digit SymbolCoding and Symbol Search subtests.…”

Mental Fatigue; A Common Long Term Consequence After a Brain Injury

“…The total sum of scores also correlated significantly with percentages for sick leave (Johansson, et al, 2009). Information processing speed is also the cognitive function most likely to be affected after a brain injury (Frencham, Fox, & Maybery, 2005;Madigan, DeLuca, Diamond, Tramontano, & Averill, 2000;Martin, Donders, & Thompson, 2000). The self-assessment scale in combination with tests that primarily measure information processing speed and a high cognitive load on attention might make it possible to evaluate problems described by patients with mental fatigue, as subjective mental fatigue after mild TBI and TBI are suggested to primarily correlate with objectively measured information processing speed.…”

Long-Lasting Mental Fatigue After Recovery from Meningitis or Encephalitis - A Disabling Disorder Hypothetically Related to Dysfunction in the Supporting Systems of the Brain

“…The total sum of scores also correlated significantly with percentages for sick leave (Johansson, et al, 2009). Information processing speed is also the cognitive function most likely to be affected after a brain injury (Frencham et al, 2005;Madigan et al, 2000;Martin et al, 2000).…”