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

Abstract

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.