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Published information pertaining to the clinical utility of the WMS-III in assessing memory impairment in traumatic brain injury (TBI) remains inadequate. WMS-III findings are reported for 180 litigants with post-acute moderate to extremely severe TBI, classified into three groups according to injury severity, and a healthy control group. A significant "dose-response" relationship was found between memory impairment and TBI severity for most of the WMS-III indexes and subtests. Effect sizes were large for the Immediate and General Memory Indexes and medium for the Working Memory Index. In general, TBI had a greater effect on the Visual than Auditory Indexes. Effect sizes were greatest for Family Pictures and least for the auditory recognition and working memory tasks. Group findings indicate the immediate memory tasks to be clinically useful in relation to a severe or extremely severe TBI, but not for less severe trauma. Delayed memory tasks do not provide information additional to that obtained from immediate memory measures. The revised Tulsky indexes are no more sensitive to the effects of TBI than the original ones. Differences between WMS-III memory indexes are unlikely to be of diagnostic utility although memory-intelligence discrepancies may be.

Two methods of predicting premorbid WAIS-III Full Scale IQ, namely a demographic measure (DP IQ) and the Oklahoma Premorbid Intelligence Estimate-3 (OPIE-3), were assessed in three traumatic brain injury (TBI) groups of varying injury severity and normal controls. On the DP IQ, average scores were in keeping with the general population mean across all groups but range was severely restricted. OPIE-3 IQ scores were not subject to severe range restriction and were comparable with the general population mean in the control and least severely brain injured group. They were significantly lower relative to controls in the severe and extremely severe TBI groups, with differences averaging around 7 and 10 points, respectively. OPIE-3 (Best) proved particularly robust in more severely injured subjects. Effect sizes for the combined TBI sample relative to controls were greatest for OPIE-3 measures that included two non-verbal subtests and were least for that involving vocabulary only. Implications of the findings for clinical practice and further research are discussed.

WAIS-III findings were reported for 150 litigants, classified into three groups according to severity of traumatic brain injury (TBI), and a general population control group. There was a significant "dose response" relationship between TBI severity and all Index/IQ scores. Effect size was greatest for the Processing Speed Index (PSI). Between group differences were significant on all subtests except Information and Digit Span. Effect sizes were greatest for Digit Symbol, Symbol Search, Similarities, and Picture Arrangement. Relative to the control group, there was a significant difference for the Severe and Extremely Severe TBI groups on all IQ/Index scores and most subtests. The Moderate TBI group differed significantly on one Index (the PSI) and none of the subtests. Clinical implications of the findings are discussed in relation to the utility of the WAIS-III in assessing the cognitive sequelae of TBI, the use of current WAIS-III IQ scores to assess intelligence-memory discrepancies, WAIS-III short forms, and estimation of premorbid intelligence.

Wechsler Memory Scale-Third edition (WMS-III) performance in 25 mild traumatic brain injury (TBI) litigants who met the criteria for probable malingered neurocognitive dysfunction (MND) was compared with 50 nonmalingering subjects. The base rate for probable MND in the population studied was 27%. Overall, malingerers showed globally depressed memory function. They returned significantly poorer scores than nonmalingerers on all WMS-III indexes and subtests, and on selected WMS-III index difference scores and intelligence-memory difference scores. Using the minimum score returned in the nonmalingerers as the cut-off for malingering, the delayed auditory recognition memory tasks were highly effective in detecting malingering. Raw scores below 43 on the auditory recognition-delayed (AR-D) subtest or below 18 on word list II-recognition, identified around 80% of the malingerers. In a group of 50 severe TBI litigants, only a very small proportion (i.e., <10%) returned scores below the cut-offs for malingering for the mild TBI subjects.