by Murph E.
Hey everyone: Check out the McGill principal’s report. Why? Because McGill really loves the photo I took of the statue of James McGill. Note the “additional photo credits” on the page I linked to, and on the inside of the cover of the PDF version of the report.
For those of you keeping score at home, this is now twice that a publication by McGill has used my photo of the statue of McGill. :)
by Murph E.
“Movember” is the name of a movement that emphasises men’s health, specifically prostate cancer awareness during the month of November, by encouraging men to grow moustaches. There are two main reasons why I will be clean-shaven this November.
When is it rational to be screened for a condition?
The first major problem I have with Movember is the emphasis that is placed on prostate cancer screening for men—even men who are not in a high risk group for this type of cancer.
Not every test is completely reliable. Think about it this way: If you put a toothpick into something you baked and it comes out dry, it’s likely that your baking is done. But it’s also possible that you just poked the wrong part of your banana bread, and the rest of it is all gooey. If that happens, it’s called a “false positive” result for your test, or a “Type I error.”
This isn’t just a problem for bakers. It’s a problem with pretty much all medical tests (or any test at all for that matter) that there is a non-zero chance that you will get a false positive (“Type I error”) or a false negative (“Type II error”) result.
For prostate cancer, there are two methods of screening: a digital rectal exam (DRE) or a prostate-specific antigen test (PSA). The DRE is a physical examination of your rectum by palpation and the PSA is a chemical assay performed on a blood draw. Neither of these tests can be relied upon to give perfectly accurate results all the time.
The problem is that if a doctor finds what he takes to be evidence of a tumour growth in the prostate, he may order a biopsy of the prostate. This is an invasive, expensive, painful (and in the case of Type I errors, unnecessary) procedure that brings its own set of medical risks. A biopsy carries the risk of infection, for example.
Please examine the decision tree I have attached to this post. I have tried to make it as general as possible. If you wanted to be really rigorous, you would assign dollar values to each of the outcomes, and then for each of the branches off a probability node (a circle), calculate the probability of that branch. Then if you multiply the probability value of that branch and the dollar value of the outcome for that branch, and take the sum of all the branches, it will give you the value of that node. Repeat the process from right to left, until you come to a decision node (a square). The branch that carries the highest value as calculated using the algorithm I outlined is the decision that one has most reason to take.
I haven’t done the research to find out what the rates of Type I and II errors are for PSA tests, but they are pretty high, and you can see that if the probability of an inaccurate test result is high enough, and the consequences for having a bad test result are dire enough, that might give you reason to go without testing, provided you aren’t in a high risk group for prostate cancer. Further, a randomised control trial of men showed that there is no significant difference in mortality between a group of men who were screened for prostate cancer and those who weren’t. The evidence shows that prostate cancer screening doesn’t help reduce mortality.
If you are in a high risk group, like if there is a history of it in your family, and you are in a certain age range, then by all means, you should be tested for prostate cancer regularly—but don’t start encouraging young healthy men who are not at high risk for developing this sort of cancer to go looking for it. They may find more trouble than is actually there.
The second major problem I have with Movember is their condescending and naive position on “men’s health” generally. Let’s consider a quote from the Movember Canada website:
Let’s face it – men are known to be a little more indifferent towards their health … The reasons for the poor state of men’s health in the Canada and around the world are numerous and complex and this is primarily due to a lack of awareness of the health issues men face. This can largely be attributed to the reluctance of men to openly discuss the subject, the old ‘it’ll be alright’ attitude. Men are less likely to schedule doctors’ appointments when they feel ill or to go for an annual physical, thereby denying them the chance of early detection and effective treatment of common diseases.
(From Men’s health—Movember Canada)
Movember Canada is stating here that it is “reluctance of men,” an “‘it’ll be all right’ attitude” and the general indifference toward issues of health that make men less likely to schedule a doctor’s appointment when they feel ill, or to make an appointment for a regular physical exam.
This is not the case. In Canada, men don’t schedule doctor’s appointments largely because they don’t have a doctor that they can call to make an appointment. I have been on my CLSC’s waiting list for a doctor for over a year now, and unless I go to the hospital or a walk-in clinic, I think it unlikely that I will see a doctor any time soon. This is not because I’m indifferent toward my health. This is because I don’t have a doctor.
It is not men being “too macho for doctors” that’s the problem. It’s that we as a country have made decisions regarding health care in Canada based on economics and politics that have brought about a doctor shortage. I hesitate to call it a “doctor shortage,” because the word “shortage” makes it sound like it was something unavoidable or unforeseeable—not something that was engineered and implemented as a matter of public policy.
The reason men aren’t seeing doctors in Canada is because we have chosen to limit our health care spending by decreasing the number of doctors in Canada who will order expensive tests and procedures. So don’t you dare turn around and chide men for failing to see a doctor regularly, when that is exactly what we have decided we want.
No probably not, and insofar as it is a fundraiser for prostate cancer research and survivor programmes, I think it is probably a good thing. That said, the message of Movember needs to be changed before I can support it.
by Murph E.
McGill wins the Canada Cup
This Saturday was an exciting one for me and my teammates. I woke up at 5h15 to leave for Ottawa from the McGill campus by 5h45. It was the day of the first-ever Canada Cup, and I was on the starting lineup for McGill’s quidditch team as a beater.
We did very well on Saturday. You can check out the stats for McGill’s showing at the Canada Cup, which are posted on the IQA website, but here’s the highlights:
That last point is a matter of some importance, actually. I believe there were six snitches at the Canada Cup, and three of those were McGill students. Because there were so few snitches, this meant that (contrary to tradition) a snitch from McGill had to snitch a game in which McGill was playing. Fortunately (?) in both cases where that happened, McGill didn’t catch the snitch, but the game was a blow-out, in that McGill had an advantage of greater than 30 points (the value of a snitch-catch) by the time the snitch was caught. I say fortunately, because it means that there’s no way that there could be accusations of favouritism on the part of the snitch.
Je suis le vif d'or
On Saturday, I realised a long-time dream of mine: I was the golden snitch for an actual competitive game between schools! I got to snitch two games, in fact. For the rest of the time I was busy beating for McGill. I had so much fun.
I did make a mistake in my first game, though: Minutes before the game, I asked someone where the nearest bathroom was (because I had to go to the bathroom). This was a mistake because I did so within earshot of the seeker.
Less than five minutes in, both seekers had me cornered in a bathroom, but fortunately they knocked me down when they forced the bathroom door open, and so I got a few seconds to run off. I lost them, hid, and came back to the field right on time.
I am the golden snitch
The second game that I snitched went much better. I colluded with the snitch from the other game at the time, and we both got in the car that we drove up from Montréal that morning and locked the doors. We took the car right up beside the quidditch pitch, and I leaned out the window and waved while he honked the horn. We waited for a minute while one more snitch jumped into the back of the car, then drove off into the sunset with the seekers sadly running after us.
The crowd loved it.
Eventually, after we lost them, we drove around campus for 7–8 minutes and then came back to the same parking lot where we started and got out and ran back onto the field.
For this game, the seekers were little people! I felt bad for them whenever I would knock them down or steal their brooms or headbands.
At first, the seeker from Ryerson caught me. Ryerson was so happy—their team had never won a quidditch match before! Alas, the snitch-catch tied the game and it went into sudden-death overtime. That means that game time is extended until a second snitch-catch, and the snitch doesn’t leave the field. U of T caught me the second time around, and they won.
I’ve started noticing that I take on different personalities while playing quidditch, depending on what position I’m playing at the time. When I’m a snitch, I’m mischievous and playful. You can tell, because of the headband-with-wings that I wear.
On the other hand, when I’m beating, I am very aggressive. I yell a lot and I pretend to be very upset about everything.
“Drop it!”
“You’re gone!”
“You’re hit!”
“Get off your broom!”
That sort of thing. Also, when people break the rules, I yell at them too. That way, the other player has a harder time doing the “Oh I didn’t know I was hit!” thing.
Also, sometimes the other player is honestly ignorant of a rule—I screamed my head off at a player who tried to continue to play, having fallen off his broom. I also yelled at a guy who tackled me from the back.
Yelling is one of my favourite parts of quidditch. I love pretending to be really upset about stuff. I try to make it really over-the-top so people realise I’m not actually angry, but sometimes other players don’t get it. I made another beater really angry on Saturday. Oops!
I’m normally a pretty even-keeled person in the rest of my life. I guess quidditch is where I get all my aggression out. :P
by Murph E.
"Pain Rating" from xkcd.com
“If a person feels pain, she is in pain.”
If you’re like me, this statement will seem to be true on first examination. In fact, for nurses, this is the current orthodoxy on pain: namely, that a person’s subjective experience of pain is the necessary and sufficient condition for that person to have a pain.
If you read the second panel of the comic attached to this post, you’ll see an example of the way that nurses are actually instructed to assess a patient’s level of pain. We ask a patient to rate her pain on a scale from 1 to 10, where 1 is almost no pain and 10 is the worst pain imaginable, and the level of pain reported is taken to be the level of pain that the patient is experiencing. For a nurse, there is no conception of pain outside of the patient’s subjective experience of it.
The attached comic brings up one of the major problems with this system for rating pain. The point of the comic is that because the scale is entirely subjective, there is a kind of incommensurability built in to the scale from the outset. Imagine two people who have exactly the same subjective experience of pain. If one of them has a better imagination for painful experiences, she will rate her pain much lower than her counterpart who is having the same objective experience of pain.
Nurses, however, are not worried by this definition in the slightest. In fact, it is heartily accepted and defended vehemently. At our skills lab a couple weeks ago, this definition of pain was defended roughly as follows: If you ignore a patient-client’s claim that she is in pain and withhold pain medication, you are torturing her.
I completely agree with a desire to avoid putting a patient through unnecessary pain. Further, I think I would want health professionals to adopt a policy where a person’s subjective experience of pain is considered to be a sufficient condition for that person to be in pain.
The only candidate case that I can think of for a pain that is unreal but felt would be a pain in a phantom limb. In some cases of people who have had limbs amputated, they still feel sensations or pains in the limbs even though they have been removed, and the person cannot be experiencing pain in that limb.
But even this case isn’t a very convincing counter-example to the sufficiency of a person’s subjective experience as a criterion for pain. I still want to say that a person with a pain in her phantom limb is experiencing a genuine pain, even though there is no limb to be feeling the pain.
And because the pain may be distressing to the patient, of course I would want health professionals to adopt a policy where such pain is treated like a genuine pain, and steps to alleviate it are taken.
But is it a necessary condition? That is, could a person be in pain, even though that person is not having a subjective experience of it? David Palmer wrote a moderately famous article called Unfelt Pains, in which he argues that this might be the case.
What would an “unfelt pain” look like? Palmer gives the example of a headache that goes unnoticed.
If a distraction makes me forget my headache does it make my head stop aching, or does it only stop me feeling it aching? (Analysis, vol. 14 [1953–54], p. 51 ff.)
Intuitions on this will differ, and I won’t recapitulate Palmer’s argument in its entirety here. (It’s worth looking over though.) But let’s imagine that it is the case that being distracted from a headache doesn’t stop the head from aching—rather, being distracted from a headache only stops one from feeling it aching.
If that is the case, then we have an example of an unfelt pain—an ache that is (at least for a time) unfelt.
This is more than just an academic concern. If unfelt pains exist, then this might impact a nurse’s practice in certain cases.
Let’s take distraction from pain as an exemplar case. Imagine that a person was having a pain, but has been distracted. The patient is not having a subjective experience of pain, due to the distraction. If we take the orthodox nursing position on the matter, this means that the person does not have a pain while she is distracted. If we side with Palmer, it means that the person is still in pain, but she is distracted.
Another good example to consider might be the case of a person who is in constant pain, but who has fallen into a dreamless (but unfortunately restless) asleep, in which she is having no subjective experience of pain.
If you are a nurse in charge of patient pain medication, do you discontinue pain medication in these examples? Depending on whether you think the pain still exists even though it is unnoticed, the answer may differ.
by Murph E.
I usually don’t like to write too many posts about my blog, but I’m excited about this, so I’m going to do it anyway.
Looking over my stats, fully 10% of the traffic to my site comes from mobile browsers of some sort (Android, Blackberry, iPhone, iPod Touch, etc.). Hence, I have made my blog mobile-friendly!
As of today, if you open up this page on your smartphone, the blog will auto-detect that you’re on a smartphone and not a computer. It will then properly format the content so that you don’t have to pinch-and-zoom your way to the content. Hooray!
by Murph E.
A decision is a good one or a bad one ex ante, regardless of what can be said about the results of the decision ex post. By ex ante, I mean, “as evaluated prospectively.” By ex post, I mean, “as evaluated retrospectively.”
I will give some examples to clarify what I mean.
Troi in "Disaster"
You are Deanna Troi (yes, from Star Trek: The Next Generation—don’t pretend you don’t remember this episode!) and the Enterprise suffers a terrible accident. It is about to explode. For some reason, you’re actually in command of the ship, despite the fact that you don’t wear a proper uniform. Against the advice of Ensign Ro, you decide to stick around to wait and see if someone downstairs fixes the ship before it explodes, even though you have the opportunity to escape. You have no reason to believe that anyone else is alive, but if you leave, there will be no power for anyone to fix the ship and save themselves. Fortunately for everyone, Riker and Data’s head go to engineering and save the day just in time.
Superbowl bet
You are a fan of American football, and on the night of the Superbowl, you make a bet with your friend on who will win the big game. You bet $100 on the underdog, knowing full well that they stand little chance of winning. Fortunately for you, the quarterback for the favoured team falls ill and throws up over the rest of the team. As a result, the entire team spends the next several hours projectile vomiting, and they have to forfeit the game. Your friend admits defeat and pays up the $100.
Drunk driver
You are drinking heavily, and you get into your car and drive yourself home, despite your friends’ protests and attempts to stop you. Fortunately for everyone, the streets are empty of both people and other cars, and you manage to bring yourself and your car home completely safe.
In all of these cases, ex post, you made the right decision—by that, I mean, there was an optimal result, if you consider the decision from the perspective of hindsight. Ex ante, however, in all of these cases, you made the wrong decision.
I put these examples in the order that I did because I think that readers will be most sympathetic to the decision in the first example, and least sympathetic to the decision in the last example.
In Disaster, an unreflecting analysis would say that of course Troi made the right decision—it’s the Enterprise, for Pete’s sake! They have to be all right. In Superbowl bet, you might even imagine your friend begrudgingly admitting after the fact that you made the right call (although he might say that it was “just luck,” and for some of us, our intuitions might differ). In Drunk driver, you would be hard-pressed to find anyone who would say that you made the right decision.
Decision trees
All of these cases have the same form, which I have diagrammed to the left. You can make one of two decisions—choice A or choice B. If you make choice A, you are likely to experience a very bad result, but there is a small chance that you will experience a good result. If you make choice B, you are certain to experience a mediocre result (one that has more utility than the very bad result, but less utility than the good result).
If all of these scenarios have the same form, we should give the same answer to the question as to what should be done in each situation, on pain of acting irrationally.
So even though you won $100 in Superbowl bet, you made the wrong decision. You should have declined to bet. Similarly, even though Troi saved the Enterprise in Disaster, she should have condemned Riker and Data’s head to death.
Humans are really bad at judging probabilities and systematically make certain sorts of errors. In particular, humans are easily swayed by trying to place experiences into the context of a narrative.
For example, after being told a story about a young woman who participates in feminism rallies and studies math in college, there is a non-zero percentage of people who will say that it is more likely that she will end up as a feminist banker than as a banker, which is logically impossible. (This is the “conjunction fallacy”—all feminist bankers are bankers, after all.)
You may have won bets that were long shots in the past, out of sheer luck. In fact, if you are a betting man, likely those are the bets you remember, to the exclusion of the ones with the same odds that you lost. The point is that you shouldn’t model your future decisions after such mistakes.
Also, if someone is trying to sway your decisions through an anecdote regarding his or her own success in an endeavour that is unlikely to succeed, it is also irrational to take that as evidence on which to base your decision-making process. If the story includes the line, “and against all odds, everything turned out all right,” or something like it, you should interpret that as meaning, “I made the wrong decision, but I was lucky this time,” and treat it as a cautionary tale.
The moral of the story is that you should model your thinking after Ensign Ro, and not after Troi.
by Murph E.
“John Smith,” “Bob,” and “George,” are very “common” names. That is, they were probably common once, but now, even though they have largely fallen out of use, we all still have a cultural memory of them being “common” and “normal-sounding.” We even use them when we’re trying to think up non-specific names for use in examples or clever aliases. Who among us wasn’t given a set of dummy data to enter into a spreadsheet in grade nine business class that included names like “Bob,” “George” and “Harry” in the “names” column? (Side note: the next time I need a clever alias, I’m going with “John Q. Taxpayer.”)
This summer, I started composing a short list of things I don’t know how to do. Of course, there are lots of things I don’t know how to do that could have gone on this list. It’s easy to come up with specific professional skills that I don’t know how to do: I don’t know how to commit brain surgery, milk a cow, draft legislation, pilot a Tardis … the list could go on indefinitely. But those sorts of things are not what I had in mind with this list.
This list was specifically for “common” skills—skills that are common in the way that the names “Harry,” “Bob” or “George” are common. That is, we think of these skills as being ones that most people know how to do (more-or-less), but in reality, they have fallen out of common use, or maybe never were very common.
For example, in books or movies, when someone is thrown a rope and told to tie a person or a boat or something up, every character instantly knows exactly what knot to tie and how to do it, without thinking, even if it was totally implausible for that character to know how to do that at all. In other movies, cars are hot-wired in seconds. Locks are picked with the use of only bobby pins, and by people who you would not expect to be able to do that. If you drop any character from any movie in the woods, after a brief montage, she will have caught a fish, and be frying it over a fire that she started without matches.
As for me, if I ever even lost the keys to my own apartment, I’d have no flying clue how to get back in.
For the record, I do realise that I shouldn’t aspire to master a set of skills simply because it would make me more useful in an action-adventure movie. That said, there’s a saying, that if you only have a hammer, all your problems start to look like nails. I wonder how many inefficiencies I have endured and problems I have left unsolved simply because the set of skills or tools I possess is limited. I remember my Grandpa Searles always used to carry a knife around with him, and it was useful to him all the time.
With the exception of juggling, I have no concrete plans right now to learn how to do any of these things, but they are all things that I would eventually like to know how to do. After finding this list again, I’m strongly tempted to start carrying around a pocket-knife, a length of rope and a bump key set. Maybe I can look up some YouTube videos for interesting ways to use them.
Here’s the list for your consideration.
If you have some other suggestions for things that most of us probably don’t know how to do, but might be a useful thing to know in certain contexts, please leave it in the comments.
by Murph E.
My computer’s hard disc has been bumping up against its upper limit for months, and so I’m tempted to just buy a bigger internal hard disc. I could probably get a disc with a much larger capacity for less than $100.
The only thing that’s stopping me is that I think my venerable old MacBook (whose name is “Fermat,” by the way) is about to die. It has been dying a slow death for a long time. The fan makes a “k-tuck-k-tuck-k-tuck” sound when the computer’s running, and when it’s thinking really hard, it makes a sick sort of “whoosh” sound.
When I close the lid, it goes to sleep, but only momentarily. As soon as the fan shuts off, the optical drive spins up again (making a “meh-nah-num-dee-umm” sound) and the computer wakes up. Then it remembers that the lid is closed and it tries to go back to sleep. The cycle then resumes (“meh-nah-num-dee-umm”) and continues until the battery dies, which doesn’t take too long these days. (“Condition: Replace Soon”)
This means that I have to shut down my computer entirely if I want to go somewhere with it. This isn’t such a big deal, but then sometimes when I push the button to turn on my computer, it takes a scarily long time for the screen to turn on and the optical drive to spin up. It doesn’t do this every time, but when it does, I think that I’ve turned my computer on for the last time.
Those are the most serious things, but there are a few weird little problems as well. When I have the computer plugged in to my external monitor, I always turn the brightness on my laptop screen all the way down. Sometimes, when I leave the room with the computer running, I’ll come back after a few minutes to find the screen on my laptop will be turned on. When I touch the mouse or a button on my keyboard, it suddenly switches the laptop screen off, as if my laptop remembered that it’s supposed to have been that way the whole time, and I caught it doing something it shouldn’t have.
Due to the passage of time, the plastic casing has chipped, cracked and is peeling slowly off the computer, and the little pulsing white light that’s supposed to indicate that the computer is sleeping does not work. The DVD burner is flaky at best, and the whole computer runs very hot. By that, I mean it reaches a very high temperature.
Other than that, it works just fine.
My computer has a lot of character, and we’ve been through a lot together, but since I’m afraid that it will die soon, I don’t know if I want to invest the money in a new hard disc. But then if I can squeeze another year or two out of this computer by simply investing $100 for a new hard disc, then that would be a good investment.
by Murph E.
I’ve been training hard for quidditch this autumn and periodically after practice, I crave chocolate milk. Naturally, I went looking for some. I’ve been to a number of grocery stores now, but I haven’t found any chocolate milk at all. I’ve found “chocolate dairy beverage,” but nothing that’s actually called “chocolate milk.”
This makes me wonder if there is such a thing as “chocolate milk” anymore. I know there’s strict regulations (and rightly so) on what things can be labelled “milk.” For all I know, it might be the case that anything with enough chocolate in it to be called “chocolate milk” would have too much chocolate in it to be called “milk” at all.
Now here’s where it gets weird. I can’t actually remember if chocolate milk was labelled “chocolate milk” in my childhood. It might have been “chocolate dairy beverage” back then, too, but I just can’t remember.
So here’s a question for you dairy aficionados out there: is there such a thing as chocolate milk, and was there ever such a thing as chocolate milk?
by Murph E.
This week there was the inter-professionalism seminar for students in pre-professional health services degrees at McGill. There were students in medicine, nursing, dentistry, PT’s, OT’s and speech therapists. They even brought in a panel of experts from a major hospital in Montréal to talk to us about the importance of teamwork and inter-professional collaboration.
This is a great idea, in principle, but I feel like there was something of a bait-and-switch that went on. Toward the beginning of the plenary presentation, the speaker mentioned that their approval of collaborative, inter-professional teamwork was grounded in serious clinical evidence. In fact, there was an entire slide devoted to a number of positive health outcomes for patients that we were told resulted from the approach to teamwork that the speaker advocated.
I was excited at this point. I fully expected that the next slide would tell us what the independent variable in that study was. I wanted to know what it was exactly that brought about those positive health outcomes for patients. Then I expected to be told things like sample size, statistical significance, and the limitations of the research. After that, I thought that some other complimentary studies would be offered, and they would pull it all together by suggesting areas for further research into collaborative, inter-professional work.
At McGill, at least in the department of nursing, there is a big emphasis on evidence-based practice. That is to say, we want our work as health professionals to be informed not just by our own personal biases and experiences, or even those of our teachers, but on solid, empirical, scientific, testable, repeatable, statistically significant data.
That is why it was something of a shock for me when none of my previously-discussed expectations were met. After the one slide about positive health outcomes, I think it would be fair to describe the evidence provided in support as “anecdotal” at best. The panelists each spoke about their subjective experiences of the merits of working on a team, and then we were dismissed for small group discussion.
In the small group, my worries were amplified. A number of concerns were raised by the different pre-professionals in the group. They asked about the following:
Many of the answers given by the small group leaders were vague. Often group members would give answers that contradict the ideas previously expressed. It was really difficult to see what I was supposed to take away from the seminar, and I expressed this to the group.
Maybe I’m being too optimistic, but I feel like these are the sorts of questions that could be answered empirically, at least in principle. To oversimplify, someone should find a sample of a few thousand health professionals who work on a team and collect data about the way they spend their time, the way their teams work together, what sorts of teamwork strategies/relationships exist among the team members, what sorts of health outcomes they achieve with their patients and the level of job satisfaction the health professionals experience themselves. Or if you don’t like that sort of study design, you could randomise clinicians to different teams, in which highly-scripted interactions take place and then measure the patient health outcomes and the clinician job satisfaction. There are smart people out there whose job it is to think up ways of measuring these sorts of things accurately.
Then, you give the data to a statistician and tell him to find out what things are related and how strongly related they are. Et voilà. Evidence on which to base practice. (Easier said than done, I admit.)
This is the sort of thing that I would want to know. I mean, for all I know, there may be a very statistically robust optimum for the number of hours to spend with colleagues outside of work to maximise group member job satisfaction and positive patient health outcomes. If that sort of thing is the case, then it’s something that all health professionals really ought to know.
Or consider the “comic relief” idea—it might be the case that having someone on the team who acts as a comic relief is consistently detrimental, or even that there’s no statistically significant relationship between the presence of a clear “comic relief” character on a team and job satisfaction or positive patient health outcomes.
I’m going to do some research now, because I’m honestly curious about whether or not some research of this type has already been done. Let me know if you have any good articles on the topic.
All content © Benjamin Carlisle
