Psychometric intelligence in patients with traumatic brain injury: utility of a new screening measure.

OBJECTIVE

To evaluate the validity of the General Ability Measure for Adults (GAMA) in a sample of patients with traumatic brain injury (TBI).

DESIGN

Comparison with criterion standards of Wechsler Adult Intelligence Scale-Revised (WAIS-R) and measures of injury severity.

SETTING

Regional rehabilitation center.

PARTICIPANTS

One-year prospective series of consecutive rehabilitation referrals, including 42 adult patients with TBI.

MAIN OUTCOME MEASURES

GAMA and WAIS-R IQ scores were obtained within 1 year after injury and compared with each other and with measures of injury severity.

RESULTS

The GAMA demonstrated statistically significant covariance with the WAIS-R and was able to discriminate severe TBI from mild/moderate TBI. The correlation between the GAMA and length of coma fell just short of statistical significance.

CONCLUSIONS

The GAMA is sufficiently sensitive to the presence or absence of severe TBI but may not be sufficiently sensitive to the exact degree of injury severity.