PITTSBURGH -- A Pittsburgh hospital is the first in the nation to study the effects of concussions on high school students.

The University of Pittsburgh Medical Center study was featured this Tuesday morning on "Today."

Researchers say they have found athletes who have suffered a concussion should remain out of the game until all symptoms have passed.

UPMC officials say they are now using a new computer assessment tool called Impact. The program tests the athletes on a number of levels to help doctors figure out when a student is ready to return to sports.

Dr. Michael Collins, of UPMC, said, "It's all about making sure the athlete is completely symptom free both at rest and at physical activity before allowing them to return to play."

Researchers say most student athletes begin activity too soon after receiving a concussion.