January 16, 2012

Risk Compensation Revisited

A few years ago I got interested in risk behavior, and wrote about it on this same infrequently updated blog. Fast forward 3 years and we now have a son. Theoretically and stereotypically, sons dream of playing football. Julia and I have joked about that before, and I say a manly son of mine is free to play football... so long as he's the kicker. Lewis has been growing at a rate that leaves us scratching our heads compared to our two daughters. He weighed at 3 months what they weighed at a year. (And they were right in the middle of the growth curve. So I guess he's about average too, if he were a small baby elephant.) Obviously growth patterns can fluctuate with age, but if he were to keep this up he'd be a fairly huge young man, ripe for competitive sports one might think. Grace wants to try out basketball and soccer, and who knows what Violet will take an interest in. Given her wild 3-year old independent streak it would seem full contact gymnastics would be right up her alley.

Julia just referred me to this interesting piece which is yet another article in the  popular press on the risks of concussions in football. Part of that article is a brief consideration of helmet technology, and whether or not we can invent our way out of this problem. As should be obvious from my take on seat belt laws and the like, I would argue no. In fact some people say we should get rid of facemasks and remove protective equipment to alter player behavior. The safer a player feels, the more risks they will take is the theory, and I think there's good evidence from other arenas of life to back that notion up. More on that later.

The literature on concussions largely uses the concept of Athletic Exposures. An Athletic Exposure (A-E) is generally defined as one athlete participating in one practice or a game/match. So, what is the rate of injury (in this case concussion) across various sports? Studies vary, but generally high school football is around 0.5-0.6 concussions per 1000 A-E (see Lincoln et al and Gessel et al). Those numbers may be under-appreciated. With time the rate of concussions seem to be going up. The argument is often made that we're just increasingly aware of concussions and diagnosing them more, and that may be. But how do other sports compare? According to this paper by Marshall and Spencer the concussion rate for rugby is 3.8 per 1000 A-E. That's admittedly a small study, but the article does contain a review of other published studies on the topic, and most of them are significantly higher than what the estimates are for American football. Ice hockey in various studies is also north of 3 per 1000 A-E, and individual contact sports (boxing, martial arts, etc) are higher still. So when they propose a mixed martial arts club at your kid's high school in 15 years, say no. 

Also, girls seem to be at more of a risk of concussion injury than boys. The Lincoln data show that for similar sports (basketball, soccer, baseball/softball) girls have a rate of concussion more than double that of boys. 

And girls' soccer had the second highest incidence of concussion after football. I can't help but wonder how accurate the reporting is here when we are comparing boys' and girls' sports. It would not surprise me at all to learn that the culture of boys' sports encourages them to "tough it out" and not report symptoms of concussion. But that's another topic entirely. 

From that epidemiological data, flawed though it may be, it would seem that American Football is not as bad as  some alternatives. It is the most risky of all the sports we play here though. It is also the sport that captures the national attention (sorry baseball), and the sheer volume of young men playing it means that we're talking about a whole lot of A-Es here. So what can we do about the concussions? Will better monitoring and better protective equipment reduce that rate of injury? So far, signs point to no. The monitoring has only served to make us more aware of concussion. This paper has a nice rundown on what is involved in monitoring head forces in football with the HITS system and what it has been showing (hint: 25g forces applied to the head about 10-15 times per A-E). What can we say about concussion risk and protective equipment? Virginia Tech has done some nice work comparing different helmets, but this is matching impact data in a lab with incidence data and drawing conclusions on which would be the most protective. There is no evidence that I can find that shows players wearing one type of helmet have a lower risk of concussion than those wearing another type. 

Padded headgear made no difference in head injury or concussion risk in rugby. In soccer (or football to all the rest of the world) there is mixed evidence. Some retrospective studies suggest headgear is protective. But controlled studies in the lab suggest that headgear doesn't provide significant protection, and broader reviews of the literature have not found a consensus agreement that they do any good. There's similarly mixed evidence on full face protection in hockey (it may be helpful in reducing severity of concussions). But in the discussion of most of these papers there is always the specter of our good friend risk compensation. This summary paper goes through what limited data there are on how interventions alter risk taking behavior. The authors note that in the 1940s American football players were taught to initiate contact with the shoulder. After the introduction of the plastic helmet they were taught to strike first with the head, and that tackling drill fatalities increased after the introduction of the plastic helmet. Surveys of rugby players showed that 67% felt more confident and able to tackle harder if wearing protective headgear. 35% of those involved in ski/snowboarding fatalities were wearing a helmet, which is well above what was average for the time in those not injured. 

In the end, most academic papers on the matter make mention of one common factor that seems to mitigate increased risk taking behavior, and makes more of a difference in injury rates than advancing technology and protective equipment. That factor? Changing the rules of the game. Commentators and good ole boys may whine about how new rules are making football not football anymore. If we banned heading the ball in soccer there would be a similar outcry I'm sure. But what we're learning is that the human skull/brain combo aren't well suited to running into things with force. Things like other skulls, the ground, the inside of a Humvee, etc. But equipment can't make inherently unsafe activities safe. Safer, maybe, but still risky to the millions of young people participating. If we really want to protect them, we have to change the games they're playing. 

October 8, 2010

The Breast Cancer Conspiracy

Cancer is bad.  I get that.  Each of my parents has survived two distinct kinds of cancer.  My grandmother died of multiple myeloma.  I'm going to say that the genetics aren't exactly in my favor here.  Now none of them were breast cancer, but I surely understand the urge to do something about it.  But this Facebook purse crap?  Uh, no.  Last year it was your bra color, this year it's purses.  We're raising awareness by being obtuse and dropping double entendre?  And what the heck do purses have to do with breast cancer anyway?  Women have purses?  And breasts?

Somehow these Facebook status updates are supposed to titillate and get so much attention that we'll all have our awareness raised about breast cancer.  Great!  But even if it works... so what?  What does awareness do in the face of a huge problem like cancer?  Awareness without action or a response is meaningless.  If we are aware of a great  truth but don't share it we haven't done anyone any favors.  As a doctor, if I'm aware of a problem but don't do anything it's called negligence.  We have vigorous conspiracy theories about politicians supposedly being aware of Pearl Harbor or 9/11 and taking no action.  Is breast cancer a conspiracy?  One where we have all manner of awareness but don't do anything about it?  Talking about it via Facebook statuses is the best we can do?

This purse wannabe-meme is ridiculous to me on another level.  It does nothing, and yet is all about  something that can effect real change.  Inside all those purses that women are innuendoing across Facebook lie wallets.  In those wallets lie money.  In money, there lies research and healthcare.  So I say we turn this silly thing on itself.  How much did that purse cost?  Give that much to cancer research.

I replace plenty of functional gadgets and gizmos with newer versions all the time, so I'm no better.  But I'm guessing that the purse replaced one that was still totally functional but out of style.  If we can afford that, we can afford cancer research for better treatment and more cures.  What if everyone gave to the American Cancer Society or some similar organization what their (or their significant other's) last purse cost?  Then you can update your Facebook status with that instead. Heck, you can be as salacious as you want about it.  "I pay $100 to get it." "I charged my husband $75 for it." Whee! We're having innuendo-laden fun now.  Or you could say what I'm about to, no innuendo required:

I donated $160 to the American Cancer Society's breast cancer efforts today.  How about you?

August 29, 2010

Neo goes running

I love the differences in how each foot will strike the ground.
From: http://goo.gl/Wpqn
Back in med school I started training for a marathon.  It seemed a good and ambitious goal.  I was excited about the prospect of saying I had done it.  What I wasn't so excited about was the part whre I have to run a whole lot to get ready for it.   Running is, generally speaking, miserable... especially in Dallas.  You have your ludicriously hot, combined with a good chance of pain.  I soldiered through, making it to about 12-15 miles at a (rather slow) time.

Then my shins started hurting.  Soon it was interview season for residency, and I was travelling a good bit.  The two combined were enough to throw me off my training regimen and I gave up.

Fast forward 5 years and I haven't really run since.  When we moved to Salt Lake City my new job afforded me the time to do some regular exercise.  So back to the running I came.  But it still wasn't much fun.  The odd thing is that part of me wants to enjoy running.  I like being outside.  I like not being a pudgy slob.  I don't really like running.

Recently Julia and I heard Christopher McDougall on NPR discussing his increasingly well-known book Born to Run.  The basic gist is this: mankind is designed to run.  We probably hunted millenia ago by running animals to death over the course of many hours. (Humans can sweat and therefore cool ourselves while exercising, our early prey couldn't, so they eventually drop from heat exhaustion... there's a pleasant thought for you.)  We didn't have big cushioned shoes when we were doing this, so why is it that we think this is how we need to dress our feet for running now?

The common wisdom is that you need the right shoes for your particular shape of foot, and that you need shoes that correct for the deficiencies in your stride etc.  But there's no real research to support this, and most of what does was paid for by shoe companies.  The military did an experiment where they assigned recruits to get running shoes specific for their foot shape or a style of shoe regardless of their foot shape.   Their results showed no difference between the groups, and possibly an increased risk of injury in those assigned shoes based on their arches.  A study in 1989 by Bernard Marti found that in his sample of over 4000 runners the most common factor in who was injured and who wasn't was the cost of their shoes.  If your shoes cost over $95 you were 2x as likely to be hurt than those who had shoes under $40.  A 1999 study out of McGill university in Montreal showed that thicker soles doubled the risk of injury.  The same authors did another interesting study where volunteers were asked to step off a slightly raised platform onto a platform covered in shoe sole material.  They were told that one material offered superior absorption, one was neutral and one had a warning that it offered poor absorption.  When stepping off onto the superior material subjects landed with significantly greater force.  The kicker is that all three materials were identical.  What varied was the advertising associated with each material.  A similar study showed that gymnasts will land harder when there is more padding beneath them.  The speculation is that they are instinctively trying to do what it takes to feel stability under them.  Or maybe it's just compensatory behavior.

So while the issue isn't fully proven, I was intrigued enough to give it a shot.  I bought some Vibram Fivefingers and set out for a quick one mile jaunt to see how my body naturally wanted to run and all that.  Well my body may be made to run, but it's gotten stupid over time.  I thought one mile would be a very conservative distance to go for my first time at this ("go slow" being the most ubiquitous advice anyone will give you about barefoot or minimalist shoe running).  The fiery pain in my calves attested to the fact that one mile is in fact not slow enough.  I was used to running a few miles at a time without it being insanely difficult.  But that was not using the same muscles as this.  I felt like the running version of Neo from The Matrix.

Runner Neo: Why do my calves hurt?
Morpheus: Because you've never used them before.  Now weep quietly.  Answers are coming.

After recovering from that I was motivated to do the homework I should have done first.  Something along the lines of 1/8th of a mile would have been a better place to start.  I've built up to about 2/3rds of a mile without a problem.  I've also started running barefoot more and in the Vibrams less.  That may well change as it gets cold here.  But the whole thing is a lot more fun, which was kind of the point.  I mean look at those dudes in the picture up top... which one looks like he's having more fun?

March 16, 2010

Why can't I choose my battery?

Mr. McGuire: I want to say one word to you. Just one word.
Benjamin: Yes, sir.
Mr. McGuire: Are you listening?
Benjamin: Yes, I am.
Mr. McGuire: Batteries.

OK, that's not how it goes. But if it were made today, that's how it should go. Allow me to descend into wanton nerdery for a minute. My wife is thinking of joining the 21st century (or perhaps the 20th) and getting a cell phone she will carry around with her and actually use on a daily basis. As anyone who has tried to call her cell # can attest, it's rarely with her, and if it is the battery is probably dead. I have been a happy iPhone user for a couple of years now. If it weren't for Twitter I don't think she'd have much motivation to get with the times, but the idea of updating on the go (as was the original intent) appeals to her.

So we're looking at our options. The iPhone is nice and all, but depending on where we move to there may not be very good coverage with AT&T. Verizon seems much more likely to work out, so we're looking at Android based phones. But regardless of what we end up getting her, I am struck by our lack of choices. Oh sure, there are a number of good phones. And with something like the iPhone you can even pick how much storage space you want on it. But increasingly that's irrelevant.

I carry only a portion of my music on my phone. The rest I can stream from my home computer, or listen to internet radio like Pandora or Last.fm. Google documents abound, our email is all web based... on mobile devices cloud computing isn't some emerging thing, it's already here. I also drain my battery to near death over the course of every single day. So what matters isn't how much storage space you can give me, it's how long my battery will last while I access all that decentralized information. And that's where I run out of choices. I can choose the storage space, or color, or calling plan, etc of my phone, but I can't do a thing about the battery. Increasingly this is what matters. Batteries are the new storage space for mobile devices. Why doesn't anyone offer the option of paying extra for a more robust battery?

Perhaps it is that we lack choices in general when it comes to batteries. It seems like they are the bottleneck to electric cars, and that by and large we haven't seen a breakthrough battery technology in a long while. But I have to believe that there will be a market for battery choice. I also wonder how long it will take before we're as fluent in battery terminology (NiCd, Li-ion, cell number, energy density, etc) as we are in horsepower, CPU clock speed or other more traditional metrics of speed or power. In the near future I think the battery is going to be the key thing we care about in a lot of devices.  Now if they can just let me care about it in the next couple of months, that would be great.

February 17, 2010

If You're Going to Salt Lake City

I recently visited Salt Lake City to interview for a position with an allergist there.  Once I found out I was going to go out there I could not stop thinking about Scott McKenzie's San Francisco.  But in my head it's something along the lines of:

If you're going to Salt Lake City
Be sure to wear a three button suit with care.
If you're going to Salt Lake City
You're going to meet some business people there.

It's a work in progress.

At any rate, the trip was very good, and we'll see what comes of it.  The opportunity seems like a really good one for a lot of reasons.  Professionally it's very good: a solo practice that is growing, with people that seem like they would be very good to work with.  The timing is right, as the doctor wants to make a decision in the next few weeks.  The area is stunningly beautiful.  Maybe for people who grew up in the mountains it's no big deal, but I sort of feel like a landlocked person visiting the ocean for the first time.  "Look!  Snow!  Mountains!  Seasons!"  The city itself is an interesting issue.

The SLC area seems to be growing, and from a professional standpoint that's of course a good thing.  We initially were looking at Portland, Seattle, etc.  While those are great places, it turns out that we're not the only ones who think so, and the market for allergists is pretty saturated.  There are a couple of advertised jobs in SLC, which says something right off the bat.  Some people speculate that Salt Lake of today is Portland or Denver from a decade or so ago.  Soon maybe it too will be a hip destination where all the cool kids will want to live.  We had some concerns about the LDS influence there, but I think we've become much more comfortable about that.  For starters the city is very kid friendly as a result of their influence, and in many ways they are fantastic neighbors.  But in SLC itself the population is only 30-40% LDS.  It goes up as you get out into the suburbs and other parts of Utah, but Salt Lake itself turns out to be a fairly liberal college town.

The LDS issue made me think on a number of levels though.  The biggest one is what it will be like for our kids.  Will they be socially isolated for not being Mormon?  If so I think it's probably our fault in large measure, for not finding some of the few thousand kids who also aren't Mormon for them to relate with if need be.  It would also be very interesting to live in a place where orthodox Christianity is undeniably the minority opinion.  If we're being honest with ourselves pretty much every place in the country fits this bill.  But we're not honest, and still hold to the notion that this is a Christian culture and a Christian country.  Perhaps in name it is, but in many respects that name has been co-opted by politics and agendas and a great many non-spiritual driving factors.  I have to imagine that living in a place where the dominant religion is not your own will help you to understand the first century church better.  It will force you to decide what it really means to live what you believe.  Plus I don't think the Mormons are going to be burning any evangelicals on the stake.

In fact, I find it interesting to ponder the very systematic and organized way that relationships are built between the LDS and their neighbors.  I was told that each house on a street is assigned to an LDS-member who lives nearby.  They are responsible for that house, regardless of what type of people live in it.  Should a natural disaster or a power outage or whatever occur, it is their job to make sure everyone in that house is OK.  Say what you will about the structure and the expansion efforts and such of the LDS church, and you could argue that being told to do these things by your leadership is merely legalism and not true spirituality, but how much of that has mainstream Christianity lost?  Maybe you're being a good samaritan because you were told to, but for the person you help the impact is the same.  I am forced to wonder what the country would think of evangelicals if each one had to look out for their neighbors and do good deeds in the name of the church.  To my discredit I don't even know most of my neighbors.  We drive all over the city to go to work, shop miles from where we live, and go to churches that have little to do with location and much to do with finding the people and the beliefs most similar to our own.  Not that these things are all bad, and some of that is a natural result of how we build our cities and organize our lives.  But I have to wonder if a little forced neighborliness would really be a bad thing.

December 30, 2009

Abandon All Hope, Ye Who Vomit Here

I am the last of my kind: the lone healthy survivor of the gastroenteritis that destroyed our household empire at the end of 2009.  It attacked the smallest among our ranks first, and then nefariously turned her against us, as she became an agent of disease, spreading the sickness wherever she crawled and cuddled.  It worked its way up the ranks from there, as the eldest child complained of "tummy hurts" from bath time until bedtime, and then vomited soon after going to bed.  Having somehow never experienced this most unpleasant sensation in her four years of life I had to explain to her that what she was doing was called throwing up.  "Why am I throwing up?" she asked innocently and imploringly.  Curse you evil virus! Curse you!

Not satisfied with taking our young, the creature aimed higher, and Julia was in its clutches from midnight on.  Rest was fleeting at best, as every 10-15 minutes someone would need attention, or a sip of water, or a run to the lavatory.

Now I sit alone in my household, the last healthy member of the family.  Every female human is passed out asleep under heavy blankets, but mercifully keeping their fluids to themselves.  I don't know how much longer I have.  I'm trusting in my immune system's years of hospital exposures to get me through this.  It's either that, or sheer willpower, because man I cannot emphasize enough how much I loathe vomiting.

Blogged with the Flock Browser

December 20, 2009

The Christmas Baby

We're getting very close to Violet's first birthday, which of course makes me reflective.  I remember all the anticipation of her coming, the lingering concern over unknowns, and the joy of her arrival.  Now as we read Grace her little Christmas books and ponder the birth of Christ, I can't help but think how wrong we get that whole event in these stories.

I understand that they're written for little kids, and that the Bible is not an obstetrics textbook, but reading them it's easy to think that Jesus popped into the manger as easily as a thought would pop into Mary's head.  Or perhaps he was delivered by the UPS man late in the night, as he sure seems to be working late around our house this time of year.  "During the night, Mary's baby was born."  This is how the kids' books put it.  Christmas carols are really no better.  "The cattle are lowing / The poor baby wakes / but little Lord Jesus / No crying He makes."  Really?  Not only is this stupid, it's horrid theology if Christ is to be both fully God and simultaneously fully human.  No human newborn I've met wakes up quiet and still, much less one woken up by a cow mooing and chewing cud in his ear.  Getting to that point is equally succinct in Grace's books.  "Mary and Joseph were very tired, but there was no place for them to stay."  Yes, Mary and Joseph were both tired.  Equally so.  Long trip and all.  Oh, and one of them was 9 months pregnant and, unless human physiology has changed significantly in the last 2000 years, in labor with her first child.  But they were both really tired.

I think it is likely the cultural norms of the 1st century that kept the Gospel authors from going into any specific details of Christ's birth, and I guess you could argue that such details aren't really necessary to understand the significance of God taking on flesh.  But I think the whole thing is more legitimate if you think about what really happened in that stable, and what led up to it.

Mary was a teenager pregnant with her first (out of wedlock) child.  I've been around plenty of teenagers giving birth to their first.  Their labors tend to be long and painful.  Mary had been riding on a donkey all day, and while they are looking for a place to stay it's entirely possible she was already in labor.  Inn keeper after inn keeper keeps turning them away, despite the fact that Mary is very obviously pregnant, and as the day wears on likely having contractions.  The Bible makes no mention of the desperation that Joseph and Mary must have been feeling.  As they go around the city they must be increasingly aware of what is about to happen, and increasingly aware that they will not be able to deal with it in the usual fashion.  I recall my weak attempts to meet Julia's needs as she labored, in an advanced medical facility, and can only imagine what powerlessness Joseph felt as he couldn't even find a room.  Angels did not promise her an easy labor, or forewarn them that they'd be staying the night in a place that smells of animal waste and moldy hay.

But that's exactly where they ended up, at some point deciding that this was their best option.  Mary is fully in active labor soon, and since the Bible makes no mention of a third party, there is no midwife in sight (unless the cow counts, because I bet she's given birth a few times at least).  This means that not only did Joseph accept that his bride-to-be is pregnant with God's son and not send her on her way, he was the only person available to help Mary with the delivery.  There is no reason to think that Joseph had ever been present at a birth before, or that he had any clue what to do to assist Mary.  He surely had no idea what to do if something went wrong, which had to be on his mind and Mary's.

After a long and painful labor Mary gives birth to a screaming baby boy with blueish hands and feet.  She does not wrap him in swaddling cloths and plop him down in a manger straight away.  Joseph wipes him off as best he can, and Mary puts him on her chest, where he tries his first feeble attempts at nursing.  Contrary to the happy pictures we see, Mary is covered in sweat, if she's anything like my wife she's popped a few blood vessels in her cheeks or eyes, and she's utterly exhausted, but at the same time ecstatic.

This is what I think Jesus Christ's birth was really like.  Scary, difficult, and not at all according to the normal plan.  But such is life, and if Jesus is to have experienced all that man has to go through, I can't imagine a more fitting way for it all to start.

And then some random shepherds scrambled into the stable in the middle of the night.