How robust is performance on the National Adult Reading Test following traumatic brain injury?

Objective. To investigate whether National Adult Reading Test (NART) performance may be impaired by severe traumatic brain injury (TBI). Method. A sample of 26 people who had been given a NART within 12 months of a severe TBI was given a second NART at least 12 months after the first NART. Results. Mean performance on the second NART was significantly better than performance on the first NART. Of the participants, 11 (42%) showed an improvement of more than 5 IQ points in respect of the verbal IQ estimates based on their NART scores, with three participants showing an improvement of 20 points. In applying the NART to determine the presence of an acquired intellectual impairment, use of the first NART scores alone would have resulted in such impairments being missed in at least 25% of a subsample of 16 participants for whom an actual verbal IQ had been obtained at the time of the first NART. Conclusion. An NART given within 12 months of a severe TBI runs the risk of significantly underestimating pre-morbid IQ. If applied in this context, it is recommended that the NART score is used in conjunction with other methods of estimation, such as those based on demographic data.