treatments, and all were delivered to patients in the chronic phase with moderate-severe injuries. The committee did not identify any studies assessing CRT interventions for attention in patients with mild TBI. Table 7-1 presents a summary of all included studies in this review.
Subacute Phase of Recovery
Comparator Group: Non-CRT Content
Gray et al. (1992) compared approximately 17 hours of computer administered modules stressing various dimensions of attention to about 12 hours of recreational computing that excluded externally paced tasks or tasks that required rapid processing and responding. This study found a positive effect of training on psychometric measures of attention, particularly the type that require numerical manipulation in working memory. These effects grew in significance in follow-up compared to the immediate posttreatment measures. This pattern is of some concern, since the median time postinjury was 20 weeks, a point at which natural recovery may be ongoing; therefore, imbalance in the acuity of injury between groups might produce such a result. However, time postinjury was statistically controlled for, and measures of functions unrelated to attention did not show greater improvement in the treatment group, lending some specificity to the findings. In this study nearly half of the subjects had nontraumatic injuries, but the authors report no interaction between diagnosis and treatment benefit. The credibility of this study is compromised due to its nonreporting of sample sizes for analysis posttreatment, especially at the 6-month follow-up. Furthermore, standard deviations of the outcomes were not provided.
Comparator Group: Other CRT Content
Novack et al. (1996) studied participants who were 3 to 6 months postinjury. This study was conducted in an acute inpatient rehabilitation population approximately 3 to 6 weeks postinjury, a time when many of the patients were confused and highly impaired. One group received a structured program of attention training. The other group received a variety of other rehabilitation interventions that involved cognitive rehabilitation components that did not specifically focus on attention. Outcomes were assessed with respect to several psychometric measures of attention as well as the Functional Independence Measure (FIM). Both groups improved significantly from pre- to posttreatment, but to a comparable degree.