Marquette researchers find NFL rule decreases concussions, increases lower-body injuries

February 16, 2017

MILWAUKEE — Two Marquette University economics professors in a study forthcoming in the Journal of Health Economics have found that the National Football League's "Crown of the Helmet Rule" (CHR) reduces the probability of a concussion occurring among players by 32 percent.

However, the study by associate professors of economics Dr. Andrew Hanson and Dr. Nicholas Jolly also shows strong evidence that because the CHR forces players to alter the way they play, it has the unintended consequence of increasing lower-body injuries by as much as 34 percent. Hanson and Jolly also found that the CHR has a significant cost associated with it.

"On net, comparing the benefits of reduced concussions, as well as head and neck injuries, the CHR is quite costly for players," he said. "We estimate the one-year cost from lost productivity due to games missed to be $27 million, while the long-term net cost to be $285 million."

To arrive at a health-related cost, Hanson and Jolly used a measure called the "Value of Statistical Life," which assigns dollar values based on the severity of injuries that result from traumatic events, such as automobile accidents. They applied Department of Transportation guidelines to assign a classification of "moderate" to lower-body injuries and "severe" to concussions.

To assign actual dollar values to these injuries, the team also used DOT estimates, which assign a value of $0.43 million to moderate injuries and $0.96 million to severe injuries.

"We used our estimates of how many more lower-body injuries occur and how many fewer concussions occur as a result of the policy, and multiplied by these values to come up with the total cost of the policy," Hanson explained.

"The costs we calculated are for injuries that occurred during the season after the implementation of the rule change," Jolly added. "It remains to be seen how these calculations will evolve over time."

Hanson says the rule, which the NFL implemented after the 2012-13 season in response to litigation and an overall concern for worker safety, was well intentioned but ultimately harmful.

"What we are finding is that it is, on net, a negative thing," he said. "The cost outweighs the benefits."

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