Two Boston researchers are among a list of scientists nationwide who have been awarded grants to study the effects of repeated head injuries in a new initiative by the federal government and the National Football League to better understand these injuries and improve the diagnosis of concussions.

Traumatic brain injuries are a major public health problem that affects all age groups and is the leading cause of death in young adults, according to the National Institutes of Health.

Concern has been raised recently about the potential long-term effects of repeated concussions, particularly in those most at risk: young athletes and those engaged in professions associated with frequent head injury, including men and women in the military. Current tests cannot reliably identify concussions, and there is no way to predict who will recover quickly, who will suffer long-term symptoms, and which few individuals will develop a progressive brain degeneration, similar to Alzheimer’s disease, called chronic traumatic encephalopathy (CTE).