Functional outcome from traumatic brain injury: unidimensional or multidimensional?

This study compared multidimensional and unidimensional measures of functional outcome from traumatic brain injury in a referred sample of 67 persons with moderate to severe traumatic brain injury who resided in the community or in a nonhospital facility. Four outcome indicators (independence in self-care, independence in travel, paid employment, and friendship) were correlated with the patients' ratings on two unidimensional outcome measures, the Disability Rating Scale (DRS) and Glasgow Outcome Scale (GOS), and on a multidimensional outcome measure, the Craig Handicap Assessment and Reporting Technique (CHART). The results showed that the CHART Occupation and Social Integration scales were associated with different outcome indicators, controlling for overall outcome as measured by the DRS and GOS. DRS and GOS ratings were associated more strongly with the self-care and travel indicators than with the employment or friendship indicators. The results support a multidimensional model of functional outcome from brain injury, suggest that the CHART may measure some outcome dimensions more specifically than do the DRS and GOS, and point to limitations of unidimensional outcome scales.