As it turns out, not all concussion test methods are created equally – or even provide accurate results.

According to a recent USA Football article, the placement of sensors can skew concussion findings by as much as 500 percent, a Stanford University study shows.

The study measured head movement from the three areas of the head most used to measure head impacts: just below the ear, inside the skullcap and embedded in a mouth guard. Subjects had sensors placed in each area and then were asked to head a soccer ball to measure impact on the skull. The exercise was also recorded using high-speed cameras to view head movement in conjunction with the sensors measurement.

The results of the test show the mouth guard was the most accurate indicator, showing less than one-millimeter difference compared to video measurement. Meanwhile the skin patch and the skullcap readings were not as accurate and caused the over prediction of acceleration by up to 500 percent.

According to the article, this number can make it difficult to study the cause of head injuries.

“If these devices over-predicted consistently, say, they were always 50 percent over, then it’s probably not a huge issue,” Stanford researcher Lyndia Wu told Futurity.com, a research news site for universities. “But the problem is that they don’t correlate with skull motion, which makes it difficult to interpret their measurements, and in turn makes it difficult to interpret injury risk predictions.”

While many are quick to jump the immediate conclusion that the game of football is too dangerous to play, we must understand that even the processes of evaluating the dangers of the game can be flawed and that much more study is needed to come to an accurate conclusion on the dangers of football.

Without a doubt, football is a violent and dangerous game but with the advancements of technology and today’s understanding of concussions and head trauma, steps are continued to be taken to make the game safer each and every day.