Friday, November 30, 2007
Thursday, November 29, 2007
When I write these Thanksgiving posts, I try to pick something very particular to focus on as I'm sure every year, there is a common battery of thanked things. This year, I'm thankful for Thanksgiving. To see friends I haven't seen for years (or year, I guess) was the happiest ever. I have ineffable gratitude for those things outside of school that allow me to maintain who I am. It's so incredibly easy to get consumed by medical school such that it becomes your identity. I'm struggling to keep my head out of that water. I'm spending more time with friends, seeing more of the city, eating at different restaurants, even reading up on more non-syllabus things (http://caseoftheday.blogspot.com/). Sometime soon, I'll start regretting this when I realize that efficiency of studying is all that counts in Boards. But right now, I'm so thankful that these things, hardly career-directed, are part of my life. The anticipation keeps me awake in lecture each day. The memories keep me warm as I'm walking back home.
Wednesday, November 28, 2007
On a hill overlooking an automobile factory lived Bill, a retired geneticist, and a retired biochemist (nobody knew his name). Every morning, over a cup of coffee, and every afternoon, over a beer, they would discuss many issues and philosophical points. During their morning conversations, they would watch employees entering the automobile factory below to begin their work day. Every afternoon, as they drank their beer, they would see fully built automobiles being driven out of the other side of the factory.
Both were wholly unfamiliar with how cars worked, and they decided that they would like to learn about the functioning of cars. Having different scientific backgrounds they each took a very different approach. Bill, not being inclined towards hard work (like most geneticists), immediately came up with a scheme that he thought would lead him to an understanding of cars. The next morning he went down the hill and tied the hands of one of the workers in the factory. He then went back up the hill and sat down to have a cup of coffee. As he was just starting to sip his cup of coffee, he heard some banging noises and went out to the garage to see what was going on. When he looked in the garage he found that the biochemist had gotten one of the cars from the factory and was already covered with grease and oil as he was doing something under the hood. When Bill asked the biochemist what he was doing, he replied, "I'm taking the car apart to see how it works." The geneticist laughed out loud and then sat down to make fun of the biochemist. Bill kept telling him that he was wasting his time and that he had a much easier scheme for learning more about the functioning of cars.
Towards the end of the day, as the exhausted biochemist was washing up, the geneticist pointed to the factory below. Cars were rolling out of the factory, and each one lacked a particular circular device (the steering wheel). Moreover, each of the cars failed to make the first turn in the road as they left the factory, and all the cars were piling up on the lawn. "Hah!" exclaimed the geneticist. "The worker whose hands I tied today is responsible for installing the circular device, and the circular device is responsible for steering the car." The geneticist then asked the biochemist what he had learned that day. The biochemist said that he had been focusing on a small white object (the spark plug) and that he did not yet know what it did. The geneticist hooted with laughter.
The next day, the geneticist, emboldened by his success, went back down the hill and tied the hands of another worker. He then went back up the hill, got a cup of coffee, and sat down to another day of making fun of the biochemist. The biochemist again spent the day working in the grease and oil. At the end of the day Bill asked the biochemist what he had learned, and he replied: "I think that a component of the white object is made of an electrically conductive material, and it is surrounded by an insulator." The geneticist just chuckled. They then turned to look down the hill and noticed that there were no cars coming out of the factory. Bill seemed puzzled.
The next day the geneticist, unfazed by the puzzling result of the day before, went down the hill and tied the hands of another worker. He then went back up the hill to get a cup of coffee. As he sat down to his coffee, he heard an explosion in the garage. He ran out to see what had happened, and he found the biochemist picking himself up off the ground, his face black and most of his hair burned away. When Bill asked in amazement what had happened, the biochemist simply replied, "I have found that the liquid in the tank of the car is fairly explosive." Later that day, when they looked down at the factory to see the effect of Bill's experiment, they observed that all the cars that came out of the factory appeared to be completely normal in their function. Bill decided that the worker whose hands he had tied did nothing important for the factory.
This continued for many days. The geneticist gloated over his every discovery. For instance, at the end of one day the cars that rolled out of the factory were missing the front and rear windows, but not the side windows. Bill told the biochemist, "The worker whose hands I tied today is responsible for installing the front and back windows, and this process is independent of installing the side windows." One evening, as they were drinking some beer and arguing, the biochemist said to Bill, "Now that you have learned so much, tell me how the car works." Bill seemed puzzled by the question, but after thinking a while he said that he had noticed that whenever the cars don't have the round things (the tires) they are completely unable to go anywhere. He therefore concluded that these round things were actually responsible for moving the car. The biochemist had another sip of his beer and noticed how beautiful the sunset can be after a good day of hard work.
Meanwhile, the biochemist, after many months of hard work, thought that he was beginning to define some pathways. In one pathway, he found that the explosive liquid in the tank moved through a small pipe to a device that turned it into a vapor, and that the vapor was sucked into some cylindrical chambers. In another pathway, an electrical current flowed from a battery to the white devices he had studied earlier, and then formed a spark that ignited the explosive vapor, thus forcing the pistons out. The biochemist had also gone down the hill and taken the time to look at the cars that failed to leave the factory when Bill had tied the hands of some of the workers. He found that they were lacking carburetors, spark plugs, drive shafts, gasoline, etc. By studying these cars, he was able to confirm some of the theories that he had developed regarding the functions of the car's components.
After a while, the geneticist decided that he now knew enough about cars, and that he wanted to get one so that he could go surfing and to movies while he waited for the results of his experiments. He was running out of workers' hands to tie, so he was doing more and more elaborate experiments in which he tied several workers' hands in different combinations. In any case, he decided to get a Volkswagen Camper Van because he could fit his surfboard into it. The day he got his van, he stopped by the garage to see what nonsense the biochemist was up to. The biochemist was sitting in the car pumping the clutch, and each time he did a stream of liquid shot out from underneath the car. He told Bill that he thought the liquid in the tube leading from the clutch pedal to the clutch played a critical role in disengaging the gears from the drive shaft. Bill laughed and then drove off to spend the day at the Three Stooges Film Festival that was showing at a nearby theater.
One day Bill got in his van, but when he turned the key, nothing happened. He wasn't sure what was wrong, and he wondered whether or not his car might need new wheels. He tried the key several more times and then got out and started to walk. Pretty soon it started to rain. When he got home, the biochemist, who was drinking beer and reading James Joyce's Ulysses, asked him where he had been, and Bill told him what had happened. Bill confessed that he did not know what to do, but the biochemist said that he might be able to help. The next day they drove back to Bill's stalled van. The biochemist, not being afraid of getting his hands dirty or doing a little work, looked under the hood of Bill's van. He rapidly determined that one of the battery cables no longer made a good connection, and he had the car running in no time at all. As Bill drove away, he just shook his head.
Bill's car kept breaking down, and every time the biochemist had to go out and fix it. He tried to teach Bill how cars work, but Bill didn't seem to understand and was always more interested in his hand-tying experiments. Finally, this all came to an end when the geneticist crashed his car into a tree. Unfortunately, he was not wearing his seat belt because when he had tied the hands of the worker that installed them, the cars that came out of the factory seemed to function fine, so Bill had concluded that seat belts were vestigial and not important to the function of the car. The doctors said that Bill suffered substantial brain damage, but none of his colleagues ever noticed any difference in his behavior.
Tuesday, November 27, 2007
On a hill overlooking an automobile factory lived Doug, a retired biochemist, and a retired geneticist (nobody knew his name). Every morning, over a cup of coffee, and every afternoon, over a glass of beer, they would discuss and argue over many issues and philosophical points. During their morning conversations, they would watch the employees entering the factory below to begin their workday. Some would be dressed in work clothes carrying a lunch pail; others, dressed in suits, would be carrying briefcases. Every afternoon, as they waited for the head on their beers to settle, they would see fully built automobiles being driven out of the other side of the factory.
Having spent a life in pursuit of higher learning, both were wholly unfamiliar with how cars worked. They decided that they would like to learn about the functioning of cars and having different scientific backgrounds they each took a very different approach. Doug immediately obtained 100 cars (he is a rich man, typical of most biochemists) and ground them up. He found that cars consist of the following; 10% glass, 25% plastic, 60% steel, and 5% other materials that he cold not easily identify. He felt satisfied that he had learned of the types and proportions of material that made up each car.
His next task was to mix these fractions to see if he could reproduce some aspect of the automobile's function. As you can imagine, this proved daunting. Doug put in long hard hours between his morning coffee and afternoon beer.
The geneticist, not being inclined toward hard work (as is true for most geneticists) pursued a less strenuous (and less expensive) approach. One day, before his morning coffee, he hiked down the hill, selected a worker at random, and tied his hands. After coffee, while the biochemist zipped up his blue jump suit, adjusted his welder's goggles, and lit his blowtorch to begin another day of grinding, the geneticist puttered around the house, made himself another pot of coffee, and browsed through the latest issue of Genetics.
That afternoon, while the automobiles were rolling off the assembly line, Doug, wet with the sweat of his day's exertions, took a sip of beer and as soon as he caught his breath began discussing his progress. "I have been focusing my efforts on a component I consistently find in the plastic fraction. It looks like this (he draws the shape of a steering wheel on the edge of a napkin). Presently I have been mixing it with the glass fraction to see if it has any activity. I am hoping that with the right mixture I may get motion, although I have not had any success so far. I believe with a bigger blow torch, perhaps even a flame thrower, I will get better results."
The geneticist was only half listening because his attention was drawn to the cars rolling off the assembly line. He noticed that they were missing the front and rear windows, but not the side windows. As soon as the biochemist finished speaking (geneticists are very polite), the geneticists proclaimed, "I have learned two facts today. The worker whose hands I tied this morning is responsible for installing car windows, and the installation of the side windows is a separate process from the installation of the front and back windows."
The following day the geneticist tied the hands of another worker. That afternoon he noticed that the cars were being produced without the plastic devices the biochemist was working on. In addition, he noticed that as the cars were being driven off to the parking lot, none of them made the first turn in the road and began piling up on the lawn.
That evening, to Doug's dismay, the geneticist concluded that steering wheels were responsible for turning the car and, in addition, that he had identified the worker responsible for installing the steering wheels.
Emboldened by his successes, the next morning the geneticist tied the hands of an individual dressed in a suit and carrying a briefcase in one hand and a laser pointer in the other (he was a vice president). That evening the geneticist and Doug (although he would not openly admit it), anxiously waited to see the effect on the cars. They speculated that the effect might be so great as to prevent the production of the cars entirely. To their surprise, however, that afternoon the cars rolled off the assembly line with no discernible effect.
The two scientists conversed late into the evening about the implications of this result. The geneticist, always having had a dislike for men in suits, concluded that the vice-president sat around drinking coffee all day (much like geneticists) and had no role in the production of the automobiles. Doug, however, held the view that there was more than one vice president so that if one was unable to perform, others could take over his duties.
The next morning Doug watched as the geneticist, in an attempt to resolve this issue, headed off towards the factory carrying a large rope to tie the hands of all the men in suits. Doug, after a slight hesitation, abandoned his goggles and blowtorch and stumbled down the hill to join him.
Monday, November 26, 2007
Wednesday, November 21, 2007
Monday, November 19, 2007
"Following the Script: How Drug Reps Make Friends and Influence Doctors" Fugh-Berman, Ahari.
Here is a related youtube video:
Sunday, November 18, 2007
Reading the syllabus sections have convinced me otherwise. There are too many factors in determining the efficacy and utility of a screening test. The best way to know if a screen works is to run a randomized control trial with mortality or morbidity as the outcome. The problem is screening has inherent biases; if you catch a disease earlier, it will appear that the person survived longer regardless of whether catching it earlier had any effect on overall outcome (if there aren't good treatments, then screening has few advantages). Screening might catch things that would not otherwise have progressed to disease (mammograms have found lots of ductal carcinoma in situ but it is unclear how many of those would have lead to invasive carcinoma).
Indeed, this is compounded by the fact that treatment for cancer is associated with morbidity and mortality. Chemotherapy is hardly benign, and a physician must really think about the oath to do no harm. The efficacy ("positive predictive value") of a screening test depends not only on its sensitivity and specificity, but also on the population prevalence of that disease. Even if a screen is extraordinarily specific for a disease, if the prevalence of that disease is very low (ie. cancer), then there will be more false positives than true positives. The utility of a screen depends also on the follow-up procedure. For example, there's a fairly good screen for ovarian cancer (transvaginal ultrasound), but the confirmatory test is surgery, and 13 oophorectomies would need to be done to find one case of ovarian cancer (compare this to 838 mammograms needed to prevent a death due to breast cancer in women 50-74). Lastly, screens must be acceptable to patients; people getting screened are healthy and the threshold for tolerating procedures varies a lot (no one wants a colonoscopy).
I was pretty surprised about all of this; it really did change my view on screening tests. Furthermore, cost-effectiveness comes into play since screens are for large populations; we need to prove that the risks we are taking (money, working up false positives, diversion of resources) are really worth the benefit. In the end, I think only cervical cancer (pap smear), breast cancer (mammogram), and colon cancer (colonoscopy or others) really meet the criteria for tests with a net benefit.
Thursday, November 15, 2007
Wednesday, November 14, 2007
The other thing is the section on "JAMA 100 Years Ago" which reprints articles exactly a century before. This issue's "The Laboratory in Diagnosis" was a really good read. It is searchable, but you need a license to access it online.
Tuesday, November 13, 2007
I love children; they're fun, cute, generally healthy, curious, and excited. Most of the patients I've seen have been elementary school or younger and that demographic is just fantastic (I'm not so sure about teenagers). However, there are aspects to pediatrics (or perhaps peds EM) that I don't appreciate: the difficulty in dealing with parents who insist on antibiotics or resist vaccination, the unruly child who no one can control, the sudden mood swings and immaturity of kids trying to get their way. You also have to watch out for cases of abuse and things like that. The emergency department is interesting; it's not as scary as I would think, but it can get very busy.
Monday, November 12, 2007
Sunday, November 11, 2007
There have been many studies demonstrating the often subconscious effect of industry on physicians. Indeed, getting small gifts like pens and pads of paper have a remarkable effect on a doctor's prescribing habits even though the doctor does not realize this. In the past, biotech and big pharma had even more overt influences, offering all-expenses-paid "educational" vacations (1 hour lecture, 23 hours on the beach) or dinners at fancy restaurants in return for recruiting patients for studies. This had a detrimental effect on the objectivity of medicine and the care of the patient.
Furthermore, academic medicine and industry have to be divorced. Studies cannot be run by those with a financial (or other) conflict of interest. Studies are supposed to be objective and set the standards of care across the board; the amount of influence these journals have on medical decisions is staggering. It would be completely unethical for conflict of interests to taint such publications.
Friday, November 09, 2007
Thursday, November 08, 2007
Wednesday, November 07, 2007
This is one of those odd hypothetical questions. If someone were to give me a bolus of money (a million dollars? ten million dollars? a hundred million dollars?), I'm not sure what I would do with it. Actually, I'm pretty sure I'd do nothing with it. I'd probably pay off my loans, but I can't see myself purchasing a car or planning a vacation or buying anything extravagant. For some reason, that just doesn't occur to me. If I were particularly prudent, I would figure out how to invest the money. If I were particularly generous, I would donate. Those are things I should do. But knowing myself, I'd be strangely apathetic.
Monday, November 05, 2007
Even looking past the practical stuff, some people have the attitude that they deserve to be paid well. After all, doctors do amazing things. We replace heart valves, we insert tubes down your throat to breathe for you, we reattach severed body parts (I'm not sure how I got those examples, but note how they're all procedural). What we do saves lives. We train for decades to become proficient in it. We provide a service and we should let market forces dictate how much we get paid. Indeed, there are doctors turning towards "luxury boutique" medicine. For an annual retainer fee, these doctors guarantee same-day appointments, no waits, longer and more personalized care. Those doctors have fewer patient loads and much higher salaries. Someone's willing to pay an arm and a leg (or rather, they're willing to pay to keep that arm or leg), why not let them?