Neuropsychological assessment and the Disability Rating Scale (DRS): a concurrent validity study

Assessment of current level of functioning among clients with traumatic brain injury (TBI) often guides the establishment of realistic outcome goals for post-acute rehabilitation. Further, data generated from neuropsychological testing provide a clinician with a better understanding of a client's pattern of cognitive strengths and weaknesses. The Disability Rating Scale (DRS) is commonly used by TBI rehabilitation facilities to assess a client's general level of functioning in terms of impairment, disability, and handicap. Previous studies have used clients' neuropsychological test results to predict future level of functioning. These studies have shown mixed results regarding the predictive validity of the test findings; however, they usually employ only a limited number of tests for prediction representing a limited number of cognitive domains. Using a concurrent validity design, the present study investigated the bivariate associations between various neuropsychological testing domains (i.e. intellectual, academic, language, visuoperceptual, memory, and executive functioning) and level of functioning as indexed by the DRS. Participants were administered the DRS and the neuropsychological evaluation during the initial part of post-acute rehabilitation. Composite scores were derived for each of the neuropsychological domains. Most participants were categorized as sustaining a severe TBI. The mean age and education of this predominately male sample was 28.84 years (SD = 9.13) and 11.83 years (SD = 1.7), respectively. Results revealed a significant positive relationship between performances in intellectual, executive, academic, and visuoperceptual domains and level of functioning.