This news release describes a device that uses a drop of blood to rapidly rule out the possibility of a mild traumatic brain injury following a blow to the head. The goal is to avoid unnecessary medical exams and CT scans. The research behind the device, which is similar to a pregnancy stick test, was published in PLOS One. The news release relates that the test will be marketed next year and allows that the test is not 100% reliable. However, it oversimplifes how concussions are diagnosed, doesn’t give cost data, and relies on some sensational language. Most importantly, it skirts the lack of evidence that patients who use this device will have better outcomes or lower costs than those who don’t.
We’d all like to see better ways to diagnose the millions of concussions that occur each year. But it’s a complicated business, and there’s danger in oversimplifying the clinical decision-making process as companies rush to market devices that haven’t been rigorously tested in clinical trials. People who take such blood tests, or give them to a child, should know that they might be at risk of false assurances that could prematurely put injured people back on a playing field.
The cost of this device isn’t discussed, despite plans to put it on the market. The release noted that the standard way of diagnosing brain injuries are through CT scans. These tests run more than $1,000 a pop, at least in the U.S. The release might have noted how much this test would cost in comparison. Further, if the outcomes of the test are not improved US insurance companies are unlikely to pay for it.
The news release states that the device “will not only relieve emergency departments, free patients from often long waits, but also save on costly medical examinations.” A physician was quoted stating that the test was designed “to determine whether the athlete can return to the field or if his condition requires hospitalization.”
But it did not give sufficient data to demonstrate all of those claims. The accuracy of the test is not described by the release nor is it clear if the test improves care in any way. Also, important long term outcomes (disability, difficulty concentrating, etc.) were not part of the study so any claims made on these outcomes would be inappropriate.
The news release did state that measuring the level of one protein, H-FABP, “makes it possible to confirm that there is no risk of trauma in one third of patients,” based on a study of patients who had already been admitted to a hospital after undergoing a shock to the head. It stated: “The rest of the patients will have to undergo a CT scan to confirm the diagnosis.”
The release also stated — prematurely — that the company is “currently preparing an even more effective TBIcheck, which will allow 50% of patients to be sent home,” based on the levels of two proteins.
The news release did not mention harms, such as missing an injury due to a false negative or having a false positive result that leads to unnecessary and potentially expensive follow-up tests and treatments.
With 100% sensitivity there will be no false negatives, but that is a suspect result. It’s not clear what actions are (or are not taken) as a result of this test so it is hard to assess potential harms.
There was no data on the accuracy of this test. How often does it falsely give a negative result? And how often are people referred for further testing or evaluation when they don’t have an injury? The news release didn’t say.
More importantly, it doesn’t appear that this test has been studied in a randomized clinical trial, so there’s no evidence that patients who use it would have better outcomes or reduced costs compared with patients who are treated using current practices. That wasn’t explained in the news release.
The published study provides the sensitivity and specificity of the test but these results are only hinted at in the news release.
The news release doesn’t engage in disease-mongering; potential concussions are very common. It also provides useful context on the frequency of suspected traumatic brain injury in the UK.
The news release stated that the test sponsor, the University of Geneva, holds a patent on the test which was developed by two of the study’s authors who founded the company that will sell the test.
The news release stated that the “only reliable diagnosis is the CT Scan, which is only available in some hospitals and, in addition to being expensive, exposes patients to radiations.”
This is misleading. In fact, diagnosing a concussion is complicated. Patients are usually assessed by a doctor using the Glasgow Coma Scale—a series of physical tests for determining the level of consciousness. A CT scan can also be used in order to detect severe brain injury such as bleeding and swelling. However, patients suspected of having a concussion don’t always show signs of brain damage when scanned.
The news release stated that the device will be marketed starting in 2019 by a company called ABCDx. However, it would have been helpful to readers to point out whether or not the device must receive regulatory approvals or any details about the types of patients for whom it is recommended.
At least one other blood test to evaluate concussions has been given the green light to be marketed in the U.S., and that’s not mentioned. HealthNewsReview.org reviewed a news release and a CNN story about that device.
The headline — “A brain injury diagnosed with a single drop of blood” — was among several examples of language in this news release that exaggerated the benefits of this test. Another was that patients will have “No more doubts!” about whether they might have a concussion. It is not clear that this test will improve outcomes in any way.