text_1: Concussions in kids are detectable by blood test
text_2: This news release describes a recently published journal article on a study that evaluated a blood test that was designed to detect concussions or traumatic brain injury in children. The study reports that head injury causes the release of glial fibrillary acidic protein (GFAP) from the brain into the bloodstream, and that the levels of GFAP in the blood correspond to the severity of the head injury. According to the release, the blood test correctly identified the presence of concussion or traumatic brain injury in 94 percent of the cases. But the release fails to mention that many positive results from the test would be false-positives, which would result in additional testing and may pose additional health risks. The release notes that concussion and traumatic brain injury are usually diagnosed based on symptoms — such as perceived balance problems or reports of headaches or grogginess — and that the blood test provides an objective test that can be used for diagnosis. However, the release fails to speak to a more important aspect of the marker, that is it’s potential negative predictive value. As noted in the study the biomarker has a 98% negative predictive value. That means that a negative result, if the biomarker holds up to additional testing, would rule out concussion. According to the CDC, approximately 248,000 children were treated for concussions or traumatic brain injuries in U.S. emergency departments in 2009. And that number doesn’t include children who were taken to a family physician or who went misdiagnosed or undiagnosed. Concussions can have significant impacts on a child’s health and well-being, with symptoms ranging from headaches and dizziness to memory problems and behavioral changes. What’s more, the Mayo Clinic notes that having one concussion increases the risk of a child’s having a second concussion — and repeated concussions can have a multiplier effect. The development of an objective test that can accurately diagnose concussions in children without the use of CT scans, would certainly be a significant advance. However, it’s important to recognize the limitations of the current study and to address issues such as potential misdiagnosis.