Breathalyser test for concussion in sport

Scientists are developing a pitch-side breathalyser that can show if an athlete is suffering from concussion.

The aim is to detect chemicals in the breath shown to be associated with concussion after a blow, or series of blows, to the head.

So far they have tested only gases in the laboratory, but a trial involving 40 students could pave the way to making such a device available to professional and amateur clubs.

A controversial psychological concussion test that allows a rugby player to return to the game within a few minutes of being given the "all clear" has been