Measuring Outcome in Traumatic Brain Injury Treatment Trials

Abstract

Traumatic brain injury (TBI) involves several aspects of a patient's condition, including physical, mental, emotional, cognitive, social, and functional changes. Therefore, a clinical trial with individuals with TBI should consider outcome measures that reflect their global status. We present the work of the National Institute of Child Health and Development-sponsored Traumatic Brain Injury Clinical Trials Network Outcome Measures subcommittee and its choice of outcome measures for a phase III clinical trial of patients with complicated mild to severe TBI. On the basis of theoretical and practical considerations, the subcommittee recommended the adoption of a core of 9 measures that cover 2 different areas of recovery: functional and cognitive. These measures are the Extended Glasgow Outcome Scale; the Controlled Oral Word Association Test; the Trail Making Test, Parts A and B; the California Verbal Learning Test-II; the Wechsler Adult Intelligence Scale-III Digit Span subtest; the Wechsler Adult Intelligence Scale-III Processing Speed Index; and the Stroop Color-Word Matching Test, Parts 1 and 2. The statistical methods proposed to analyze these measures using a global test procedure, along with research and methodological and regulatory issues involved with the use of multiple outcomes in a clinical trial, are discussed.