Mild traumatic brain injury is a significant worldwide public health problem. More than 80% of all traumatic brain injuries reported are categorized as mild TBI, or rather "concussion", and incidences of mTBI account for more than one million hospital emergency department visits per year in the U.S. alone.

Mild traumatic brain injury is not an infrequent injury, and it is certainly not reserved only for Soldiers or athletes.

"Anywhere from 25-50% of individuals walking down the street report a history of at least one mild traumatic brain injury or concussion in their lifetime," said Dr. Michael McCrea, professor of Neurosurgery and Neurology at the Medical College of Wisconsin- Department of Neurosurgery Clinical Research.

In an effort to better understand the injury itself, as well as determine a technique to most effectively and accurately predict the incidence of mTBI, the U.S. Army Medical Research and Materiel Command's Military Operational Medical Research Program has teamed up with Dr. Michael McCrea and the Medical College of Wisconsin in conducting a head-to-head trial study of neurocognitive test batteries for assessment of mTBI.

Mild TBI has not only made its way into the military realm, it is now considered the "signature wound" among U.S. military personnel involved in both Operation Enduring Freedom and the Operation Iraqi Freedom. Official reports from Defense Medical Surveillance System and Theater Medical Data Store indicate that more than 178,000 Servicemembers were officially diagnosed with traumatic brain injury between the year 2000 and 2010.

A number much too large to ignore.

With concussive mTBI injuries occurring more and more frequently, increasing light is being shed on this tricky and complex injury.

"There are many neuropsychological tests that are used in the sports field and in the Military setting that have claims of concussion diagnosis or prediction of the probability of a concussion occurring," said Dr. Valerie Trabosh, senior scientist and manager of the Physiological Health Portfolio within the Military Operational Medicine Research Program.

"The overall objective of this particular trial is to compare those different neurocognitive assessment tests to determine which is most clinically effective in assessing the effects of mTBI and providing objective information on recovery that will assist in decision making about an individual's fitness to return to activity after mTBI," Trabosh said. "Currently, the Army uses Automated Neuropsychological Assessment Metrics to screen for concussed individuals. There are however other neuropsychological tests available that may have higher precision and accuracy than the ANAM, but no formal head-to-head comparison has been done which is why it is exceptionally important that this study is funded."

A number of computerized neurocognitive assessment tools for the evaluation of mTBI have been developed in recent years, however, "the validity of each of these tests is in question and Dr. McCrea is doing an imperative comparison to assess which test is most effective for assessing concussion," said Trabosh.

McCrea said, "mTBI is a different animal altogether from moderate and severe. Not even all mTBI are created the same."

Therein lies the challenge.

"While no single study can alone provide the necessary data to change policy, the implications of this study, mand others similar to it, would give the Army the information it needs to determine which neurocognitive assessment tool is most efficient for predicting the diagnosis of a concussion," said Trabosh.

Dr. McCrea's mTBI head-to-head trial directly aligns with the U.S. Army Medical Research and Materiel Command's areas of interest within the Military Operational Medicine Research Program, specifically relating to Injury Prevention and Reduction and Psychological Health and Resilience.

This three-year study began in FY12 and will run through FY14.