CTE Study: Stop Hitting Yourself!

  1. CTE Study: Stop Hitting Yourself!
  2. CTE part II: No, really, stop hitting yourself

By: Rich Sharp

Football is a violent game that humans aren’t supposed to play. But it is entertaining. Fortunately, we can tide ourselves over in the off season with a steady stream of head pounding action from the MMA and Olympic rugby (holy cow Fiji!) until the NFL and student-athletes of the NCAA take to the gridiron and expose themselves to concussions and sub-concussive strikes for our viewing pleasure (and to enrich their minds). Chronic traumatic encephalopathy (CTE), the progressive degenerative brain disease stemming from these collisions, has been cited or implied in the ongoing stream of early retirements, newly diagnosed cases, and rules changes.

And the hits just keep on coming.

At first I thought, “Great, just stop banging my head on the keyboard, and I’m off the hook.” That feeling of comfort lasted for about a week, and then we started hearing the kids saying “Seahawks colors” instead of “blue” and “green”.1 Uh oh. The desire among 2- and 4-year-olds to mimic is basically unstoppable,2 so it’s only a matter of time before they ask me to sign them up to play. Carefree self defenestrated. The “not my problem” argument just got thrown out the window, and we now have to decide which, if any, contact sports to allow them to play. Even worse, there’s a lot we don’t know about CTE, so we face a lot of uncertainty when making the decision.

Uh, So What Don’t We Know About CTE?

We don’t know how to diagnose it in living players.

We don’t know how often it occurs in the general population.

We don’t know a safe exposure level (how many concussions) or if there is one.

We don’t know even if it’s an actual disease.

Hold on, we don’t even know if it’s a disease? Well, there’s a serious debate. On one side, we have a solid hypothesis: getting hit in the head a lot is very bad for you, but, on the other hand, we know next to nothing about what’s happening at the time of the exposure or for years afterward. “By design,3 epidemiology studies cannot establish causality; they can only identify risk factors for a given disease.”4

There are groups such as the AACN who correctly make the point that no cause/effect relationship has been conclusively established. However, the AACN (or at least its president) then takes the ungrounded position that nothing should be done until we know more.5

The good news is that the medical community has jumped on it. The experts are working day and night to get us the answers we need.6

CTE: Known knowns, known unknowns, and other no-knows

There are some things we know, or at least think we know, about CTE, and now that CTE is recognized and studied the list of knowns is growing.

CTE is a progressive degenerative disease found in athletes and soldiers with a history of brain trauma, both concussive and sub-concussive impacts.7

Long observed in boxers, it was only recently connected to other sports. Dr. Bennet Omalu described the first instance in a former NFL player in 2002, and dozens of similar diagnoses have since been made in athletes from football (even a high school player), rugby, hockey, BMX, and soccer.

Symptoms include persistent pain, difficulty concentrating, disrupted speech, memory loss, impaired judgment, impulse control problems, aggression, depression, suicide, and eventually, progressive dementia. The onset of symptoms can be delayed for years following the end of exposure.

Currently, CTE can only be diagnosed post-mortem. The brain is sliced and stained in order to observe the buildup of the protein, tau and other indicators. This is a big part of the invisible asterix at the end of every CTE headline: everything we know comes from a sample of people who we already suspect had the disease and we only get to look at the wreck long after the ship has sailed.

There have been a number of notable cases: Junior Seau, Bob Probert, Wade Belak, Derek Boogard, Rick Rypien, Todd Ewen.8 Add in the examples from baseball, rugby, that high school football player, if you don’t already go too linky in the above paragraph.

What’s your prior?

OK, so before we tackle9 the problem from a parenting angle, you should understand where I’m coming from. CTE is a hotly debated topic,10 and it’s going to be important to understand my background motives: and those of the experts and opinionators.

We’re constantly looking out for the physical well-being of our kids, but a balanced approach is needed if they’re ever going to have some fun. There’s no teacher like experience, so the tooth my son lost taking a header off the couch or the unintended fall into a lake are probably net positive in the long run. The kids know some of their limits now that they’ve gone a little over them (but not over a cliff). We swore off helicoptering before they were born, and we do our best to check ourselves and calmly tell them to brush it off when there’s a tumble.

OK, balanced approach. So where’s that line between falling in a lake and falling off a cliff when it comes to contact sports? We have already decided that there won’t be any boxing or football in their futures due to the potential for brain injury. Blows to the head are the whole point in these sports, they are not accidents. It’s literally the point in boxing, it’s standard practice in football, and the phrase in soccer is “header.”

I played sports like basketball and soccer as a kid, and it was great. There are real benefits to playing for a team and pushing yourself physically. You learn about relying on teammates and having them rely on you, the importance of preparation, perseverance, bouncing back from mistakes, keeping your head when your body and your emotions are screaming, respect for opponents, learning that a successful season is going to include wins and losses and being able to come back from those losses, and of course the fine art of trash talk.11

So the answer lies somewhere in the middle, between the bubble and the maelstrom.

Is That Your Final Answer?

So if you find yourself thinking “Ok, so you’ve already made your choice: no boxing or football. I’ll make my own choice, thank you very much.” Well, the problem is that I haven’t made a choice based on medical science. In fact, since the scientific jury is still out, no such choice can be made.12 So how can I justify making a choice at all:13 shouldn’t I wait for more studies and more certainty? Absolutely not.

Let’s back up there a second – no such choice can be made? That’s right, we’re stuck between a rock and a hard place: not enough evidence to proceed on the basis of science, and no time to delay. And no fair cheating by appealing to fate. So where does that leave us? In the same place as the factory worker who has to clean machinery with benzene, or the home renovator that strips lead paint or asbestos out of an old building. The government and industry have partnered for decades to address the issue of safe exposure limits in the workplace. Workers have been exposed to thousands of chemical compounds in the workplace. By observing the health effects on willing volunteers, we have found out that all sorts of bad happens when you huff fumes all day. Wow, why would anyone sign up for the boils shift? Quite a number of people, if you pay them.

That’s terrible! That’s business as usual. It’s also the reality of progress. There is literally no substitute for human testing. You start low and work your way up until somebody complains. You look for effects over an hour and over a lifetime. You don’t get to do the purely objective experiment that explores a wide range of exposure levels and conditions. So we really don’t know what happens when somebody bathes in paint thinner, but we also don’t claim that the problem needs more study before making a recommendation. Anyone can reasonably expect that it ain’t good human beings and recommend against it. You must use observations from in real-world conditions that represent some sort of compromise between management and labor: it’s not so awful that you can’t find people willing to go in there for pay. Thus the scientific record is far from complete, but people are subjecting themselves to such treatment every day. We know that there can be serious consequences for overdoing it, but we think that if we keep the dose low enough, then we’ll be fine.

This is exactly the position we find ourselves in with regards to CTE. And even still, OSHA and other governing bodies go ahead and make these trade-off decisions that allow business to continue and offer some protection for workers. On what basis can they do this? How can they morally make decisions about workers health based on incomplete data from the companies that stand to lose economically under regulation? Well, there is a way forward: the realization that the regulators, or their family or friends may one day have to face exposure under the rules. The factory owner may never have to set foot on the floor, but why is it that we keep lead out of children’s toys produced in that factory? We proceed because we must in order to progress. It’s time to be rational in the face of the unknown.14

Our uncertainty, or honestly, our ignorance of the existence, causes, and risk factors for CTE are not an excuse for calling “needs more study” and shelving the problem for another day. My kids are going to start playing sports now, and not a decade from now when the studies are complete and consensus is reached.15

Holy crud, why haven’t we cancelled recess yet?

If you feel the paranoia setting in, you may be tempted to join the “no contact sports ever” camp. What’s the harm in playing it safe? Well there are some very real harms. One is medical and related to physical well-being: there is a childhood obesity epidemic in the US.16 Children need active play, and sports are a great way to get them doing it. Also, no single concussion-free sport like swimming17 will motivate everybody. To keep kids engaged, they need to be having fun, so we need a diversity of options. There is also the emotional development component: being part of a team, individual work ethic, and perseverance in the face of adversity. Depriving children of sport is harmful.

But brain damage? CTE? A lifelong and life shortening degeneration of the mind? That’s not up for discussion. Risks like twisted ankles and broken bones against the benefits of sports. I don’t ever want my kids to get hurt, but I’ll accept it if they do. Hopefully they can draw some inspiration from the likes of Buster Posey if they ever have to miss playing time due to injury. At least they can rest assured that I’ll drone on and on about him if the situation ever arises.

The problem for parents (until 2026?) is that, in or out, there’s an actual risk of harm. To approach it, we’ll need to figure out how to make decisions under very high uncertainty to weigh what we do know against what we don’t. Can we even make a principled decision under these circumstances? Is it possible to act rationally? Let’s see if we can’t find a way to live long and prosper.

So What next?

Now that we know a little bit about CTE and that the problem we really face is a decision and how to make it, rather than advancing the science of CTE, how do we proceed? The good news is that there is some precedent for such decisions.

In part 2 we’ll take a look at approaches to setting occupational exposure limits and find a number of parallels as well as some guidance. This should help us structure the problem better and open the door to some thought experiments.


1 It’s not my fault, I swear. You try to bring them up right (Go Niners!), but the whole city’s out to get you.

2 Results of a dependant four year study: N = 2, p = 10-(are you freaking kidding me?)

3 This isn’t just some convenient cop-out on the part of the NFL or their storied predecessors such as big tobacco. To run a proper study in these cases would mean running it like a drug trial: choose people who get different doses. Raise your hand if you’d like to volunteer to be dosed by a lab assistant with a rubber mallet.

4 http://www.nature.com/neuro/journal/v12/n12/full/nn1209-1475.html.

5 See the conclusion of this New York Times piece, where the president of the AANP says she’d be happy for her kids to play football – note also that this at least brings the standard for the policy up to the level of “self-infliction” (see Ch. 5 of SVE’s safety limits book).

6 BU has launched a 7-year study aimed at diagnosing CTE in the living.
The quadrennial 5th International Consensus Conference on Concussion in Sport will be held in October 2016.
There is debate as to whether CTE exists and the consequences of asserting that it does based on incomplete information.

7 At least according to the BU camp, which dominates the current narrative. However, statements like “CTE is” are troublesome. What “CTE is” is debateable.
8 See the supplementary chart: CTE Cases.

9 Pun intended.

10 http://profootballtalk.nbcsports.com/2016/03/29/lingering-cte-debate-launched-new-lawsuit-against-nfl/ and http://www.standard.net/Sports/2016/02/07/football-concussion-cte-debate-utah.

11 The trash talk lessons probably need to be put on hold until they understand irony. You don’t really need it, anyway, until you’ve graduated to beer league softball.
The diligent student is referred to C. Clay’s seminal oral history: I Am the Greatest, Baller Frame of Mind’s.com’s NBA anthology (including S. Pippen’s inimitable “Just remember, the mailman doesn’t deliver on Sundays, Karl.”, or the more diverse collection at Bleacher Report, which contains A. Ovechkin’s studied simplicity: “You think season is over?”

12 Cite SOH, Ch. 5.

13 I’m glad you asked. Look for the next installment in this series where we investigate similar decisions in the realm of chemical exposure limits in the workplace and the general art and science of decision making under uncertainty and ignorance.

14 These considerations of the scientific and ethical tasks faced when forming exposure limits are drawn from Sven Ove Hannsen’s Setting the Limit: Occupational Health Standards and the Limits of Science.

15 For some interesting thoughts on the “value” of scientific consensus see Ch. 5: The Role of Science in Standard Setting in Sven Ove Hansson’s Setting the Limit: Occupational Health Standards and the Limits of Science.

16 https://www.cdc.gov/healthyschools/obesity/facts.htm.

17 It may have its own dangers, but concussion isn’t one of them unless you’re doing it really wrong.

About The Author

Richard is a Seattle area data scientist who builds predictive models and the services that deliver them. He earned a PhD in Applied and Computational Math from Princeton University, and left academia for the dark side of science (industry) in 2010, following his wife to the land of flannel. Fan of coffee, beer, backpacking and puns. Enjoys a day on the lake fishing, and, better, cooking up the catch for a crowd.

3 Comments on "CTE Study: Stop Hitting Yourself!"

  1. Patrick W. Zimmerman

    The real interesting case here is soccer, particularly with US Soccer’s new no-heading-under-11yo rule.

    Does this mean I allow Mini Zed to play soccer….but only until 11?

  2. Rich Sharp

    So there’s no suspected CTE danger if you’re not hitting your head, but of course you run the danger that your kids love it, @pzed. Personally, I’m glad I’m able to look at this before my kids start playing, not after. For parents with kids who have been playing for some time, the decision is definitely more complicated and needs to be weighed against the player’s enjoyment and long-term prospects. Of course with soccer, the decision is also more subtle than headers: yes/no. Goalies are probably safe (in this regard at least), but there is also wide variation in the frequency of headers (“ariel duels”) from league to league (try sorting on ‘Ariels Won’ here).

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