[Skip to Navigation]
December 21, 2020

Perils of Race-Based Norms in Cognitive Testing: The Case of Former NFL Players

Author Affiliations
  • 1Memory and Aging Center, Department of Neurology, University of California, San Francisco, San Francisco
  • 2Global Brain Health Institute, University of California, San Francisco, San Francisco and Trinity College Dublin, the University of Dublin, Dublin, Ireland
JAMA Neurol. 2021;78(4):377-378. doi:10.1001/jamaneurol.2020.4763

The landmark National Football League (NFL) Players’ Concussion Injury Litigation case, which brought to public attention the high prevalence of neurodegenerative disorders among former players, has now exposed a major weakness in the field of neuropsychology: the use of race-adjusted norms as a crude proxy for lifelong social experience. Under the settlement agreement, retired NFL players who undergo cognitive testing and meet criteria for neurodegenerative disorders may be eligible for substantial monetary awards. In a new class action lawsuit filed on August 25, 2020, Kevin Henry and Najeh Davenport, 2 retired players who were diagnosed as having dementia but later denied benefits, accused the NFL of systematically discriminating against Black players filing dementia-related settlement claims. The plaintiffs allege that the NFL has “repeatedly insisted that applicants’ scores must be race normed by using separate Black and White reference populations—a position that greatly reduces Black players’ chances of success.”1 In this Viewpoint, we explain the practice and perils of using race-adjusted norms and propose a new approach that could replace the current standard.

Add or change institution
3 Comments for this article
Determining Cognition and its Contributors
Charles Brill, MD | Thomas Jefferson University
The only way to determine if a player's cognition has declined due to football, is to test his cognition at the start and end of each season. Then, compare the results from the start and end of his career.

Other contributing factors, such as APOE status, obesity, hypertension, diabetes, vascular disease should also be ascertained, as well as family history of dementia and vascular disease.

Football certainly can cause CTE, but may not be the entire story of a players subsequent dementia. Current players undertake their careers voluntarily, and know, or should know the risks.
High school and college football also bear partial responsibility.
Look at changes in their test scores
Shawn OBrien, Psy.D. | Retired
All potential NFL players receive cognitive testing prior to the draft. I don't believe they use race-based norms for that. Although the tests may not be valid predictors of NFL success, deterioration in scores over time might be useful for documenting deterioration in cognitive functioning.
Head injuries from violent sports increase the risk of Parkinson's disease, too!
DAVID KELLER, MD, MS | disabled internist
I am a disabled right-handed Internal Medicine physician with advanced early-onset "idiopathic" Parkinson disease (PD).

Initially, my most troubling motor symptom was bradykinesia, which slowed my hand-writing to a crawl. I also experienced tremor in my right hand and foot dystonia, plus non-motor symptoms like severe constipation with fecal impaction, and severe non-psychological depression. All of these symptoms, except the constipation, disappeared like magic when my neurologist prescribed low-dose carbidopa-levodopa.

My "levodopa honeymoon" lasted a few years, but I eventually developed treatment-induced dyskinesias. Now, at age 64, more than 20 years
after my initial diagnosis, the cause of the relentlessly-progressive degenerative brain disease that rules my life is still not known. I have identified the following risk factors as possible contributors to my condition:

1) childhood insecticide exposure: strong epidemiological evidence implicates insecticide exposure as a risk factor for PD. My family always had pets, and these cats and dogs suffered from fleas, which were treated with "flea collars", "flea powders", baths with "flea shampoos", products which were all saturated with insecticides. As if that weren't bad enough, our home needed to be periodically "flea-bombed" - by placing a canister of "flea-fogging" insecticide in every room - whereupon the humans all went out to dinner, while these canisters automatically discharged their contents into the air, creating a thick fog of insecticide. As much as my family enjoyed the companionship of cats and dogs, I would gladly forgo the experience of having had furry pets if it might have prevented the neurological disorder that is wracking my life.

2) a history of head trauma increases the risk of PD later in life. When I was 29, a mugger smashed the back of my skull with a 3-foot length of old lumber, which knocked me unconscious for about a minute, and caused me about 30 seconds of retrograde amnesia, consistent with a diagnosis of concussion due to mild TBI (traumatic brain injury). A large epidemiological study of veterans [1] demonstrated that even one episode of mild TBI increases the incidence of Parkinson disease by 56 percent within 12 years. A systematic meta-analysis of 22 studies found that a history of head trauma that results in concussion is associated with a 57% higher risk of developing Parkinson's disease later in life.

Random violent street crime might be unavoidable, but organized sports like football, which commonly inflict concussions and TBI on athletes, can and should have their rules modified to minimize the risk of developing Parkinson's disease later in life, as well as dementia and other neurodegenerative diseases.


1. Gardner RC, Byers AL, Barnes DE, Li Y, Boscardin J, Yaffe K. Mild TBI and risk of Parkinson disease: A Chronic Effects of Neurotrauma Consortium Study. Neurology. 2018;90(20):e1771-e1779. doi:10.1212/WNL.0000000000005522

2. Jafari S, Etminan M, Aminzadeh F, Samii A. Head injury and risk of Parkinson disease: a systematic review and meta-analysis. Mov Disord. 2013 Aug;28(9):1222-9. doi: 10.1002/mds.25458. Epub 2013 Apr 22. PMID: 23609436.