| Careful study of traumatic brain injury (TBI) research in the area of intervention effectiveness showed considerable variability. This variability, however, was found to be related to the degree to which researchers controlled for critical variables, including sample size, use of control groups, and the amount of data reported. The present study had a primary purpose of investigating the effectiveness of the studies of treatment of TBI sequelae; in particular, intelligence, memory, attention, and behavior. The meta-analyses also addressed the potential contribution of age at injury, sex of the subject, severity of injury, and time since injury in terms of treatment outcome.; Journal articles and dissertations containing TBI intervention studies for the years 1970–2001 were collected through hand and electronic data-base searches. Strict inclusion criteria were used so that only studies that provided references were reviewed; however, only 32 studies met the inclusion criteria.; Effect sizes were calculated in the form of d-statistics from the intervention study data. These effect sizes were used to determine whether the variance was significant or whether it was due to chance. Basically, the reviewed interventions and analyses showed no strong support for improvement of intelligence, memory, or behavior following treatment. However, a statistically significant increase in functioning following treatment for attention was found. Attention effect sizes were not similar across studies and differences could not be attributed to chance, so these effect sizes were analyzed to determine the influence of different variables. Time since injury, subjects' injury severity, age at injury, and subjects' sex did not account for differences across studies or affect treatment outcome for attention. Only four behavior treatment studies met inclusion criteria for the current meta-analysis; therefore, the results of the analysis were tenuous.; Although the current study has its own limitations, it does support the need for further research on treatment effectiveness. This includes statistically and methodologically stronger studies and a better way to conceptualize and measure TBI sequelae so that comparative studies can be conducted. |
