This study examines the outcome of 29 individuals with traumatic brain injury (TBI) and 23 of their respective significant others, 12 months after discharge from inpatient rehabilitation services, as a means of determining the validity of a measure developed to predict psychosocial outcome. This measure consists of 18 questions that examine 12 factors and requires the rater to make a judgement about the likely impact each factor would have on the individual with TBI and significant other. Results indicate that the social work raters accurately predicted outcome according to the factors contained in the measure. Scores on the measure at discharge were also found to be associated with general psychological distress, anxiety and insomnia, depression, family functioning, and the problems related to emotion and behaviour. Although the sample size was small, there is an indication that the devised measure is useful in predicting outcome and so has clinical value in identifying adults at greatest risk of poor psychosocial outcome after a traumatic brain injury.