Donna and others,
The ImPACT test is a computerize mini-neuro-psych test battery. It is promoted to athletic departments as a method of tracking concussion. It is suggested that the team do a base line test before the season starts. This would be more common in football. Not so common in soccer, baseball or basketball. It is sold as a software package with licenses for each test administration. The tests range from $10 to $29 each based on the licensing purchased.
So, as you said, it would be great if a base line test is done.
Its primary use is as an aid to convincing trainers, coaches, players and their parents that a player should be held out of a game. It does not account for previous concussions nor can it suggest the risk of a follow-up concussion.
I believe it is used more as a system for reducing the liability of the school/league from liability. It was featured on TV locally and I did some investigation into its use. The local team doctor ( orthopedist) who supervises its use claims to be a specialist in concussion but actually just has an interest. I have read his CV and am not impressed. Unfortunately, this is a common problem in sports medicine.
It is better than nothing but I believe it offers a false sense of security about returning to play.
You can go to the ImPACT site at
www.impacttest.com.