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Anecdotally, my father-in-law was chief of staff for a small city hospital and they had a rule about not scheduling afternoon surgeries on important days like a

Anecdotally, my father-in-law was chief of staff for a small city hospital and they had a rule about not scheduling afternoon surgeries on important days like anniversaries, birthdays, etc. Basically, if the surgery started going long, you didn't want the surgeon worrying about missing their spouses birthday, birthday with their kids or an anniversary. It actually wasn't that many surgeries delayed, as the surgeon just juggled surgeries and consults/paperwork/insurance to fit. If this is fairly standard practice, then an afternoon birthday surgery would be an emergency situation and, hence, more deadly. Given the paper said some surgeons take the day off entirely, any surgeon with that habit would be performing an emergency surgery.

jlebar 6y ago
> If this is fairly standard practice, then an afternoon birthday surgery would be an emergency situation and, hence, more deadly. TFA says they're only counting emergency surgeries, to avoid exactly this bias.
- UncleMeat 6y ago
  This is the most frustrating pattern in online discussion of science. A post title presents a conclusion, then the top comment proposes some alternative cause of the conclusion or some hypothesized methodological weakness in the research, then readers assume that the research is bad. Often, the exact specific criticism appears directly in the paper because the researchers thought of that too.
  - trisiak 6y ago
    No reason to be frustrated. Things are almost never right or wrong, particularly in complex science. In this case, based on another comment above about "emergency procedure" having multitude of meanings, you're most likely wrong in that the paper has a rebuttal to the top post. The hypothesis then, is that the actual urgency of surgeries is not controlled precisely enough to state that they cannot affect the measurement.
    - UncleMeat 6y ago
      From the sibling comment. > The major threat to the internal validity of our findings is that surgeons may selectively operate on sicker and more complex patients on their birthday, perhaps because those patients cannot have their procedures delayed. However, this is unlikely to explain our findings because we found that patients who underwent surgery on the surgeon’s birthday were similar in all observable characteristics to patients who underwent surgery on other days. Furthermore, severity of illness as measured by predicted mortality, and the number of procedures performed per surgeon, also did not differ based on whether a surgery occurred on a surgeon’s birthday compared with other days. > we found that patients who underwent surgery on the surgeon’s birthday were __similar in all observable characteristics__ to patients who underwent surgery on other days
  - FabHK 6y ago
    > Often, the exact specific criticism appears directly in the paper because the researchers thought of that too. From the paper: "The major threat to the internal validity of our findings is that surgeons may selectively operate on sicker and more complex patients on their birthday, perhaps because those patients cannot have their procedures delayed. However, this is unlikely to explain our findings because we found that patients who underwent surgery on the surgeon’s birthday were similar in all observable characteristics to patients who underwent surgery on other days. Furthermore, severity of illness as measured by predicted mortality, and the number of procedures performed per surgeon, also did not differ based on whether a surgery occurred on a surgeon’s birthday compared with other days."
colonwqbang 6y ago
This is a beautiful conjecture! The problem is amusingly circular. Even if you reject the conjure in parent comment, you will be tempted to reduce the number of birthday surgeries due to the increased mortality. This will mean that birthday surgeries are only done in even more desperate circumstances which of course will increase the risk. So mitigation of this problem will lead to the percentage increasing even more! Actually, it turns out that it is possibly better if the percentage is high!
- Ensorceled 6y ago
  Yes, it does really mean you need to dig into actual causation or the law of unintended consequences will bite you in the ass.
- faeyanpiraat 6y ago
  I do not completely understand your points. Shouldn't hospitals have multiple surgeons? If one of them is on vacation, the other one does the work, and vice versa?
  - Galanwe 6y ago
    I don't think surgeons are fongible assets. There is a lot of planning and study taking place before a complex operation. Not to mention most surgeons have specialties.
    - watwut 6y ago
      The long term plans and studied for surgeries can be moved one day forward or backward basically by definition.
      - travmatt 6y ago
        Except if something changes suddenly and surgery is suddenly needed - that’s what makes it an emergency.
    - daniellarusso 6y ago
Galanwe 6y ago
> If this is fairly standard practice, then an afternoon birthday surgery would be an emergency situation and, hence, more deadly This is spot on. The causality can be both ways. Note that it would be interesting to dig into what is really computed here, because the whole wording seem intentionally sensationalistic. 1) "23% more likely to die" seems _huge_, but it applies to an already very small chance. The mortality rate just goes from 5.6% to 7%. Using this logic, moving from 0.1% mortality rate to 0.3% would mean "you are 3 times more likely to die". 2) Comparing mortality rates only make sense if the distribution of operation complexity are identical for these days. As the parent post suggest, it seems very likely that low complexity operations are postponed after a surgeons birthday. 3) Where are the confidence intervals? I refuse to even consider looking at a statistics if error boundaries and significance metrics are not provided. That may very well all be provided in the underlying paper, but the article itself does not really discuss these points.
- soco 6y ago
  Aren't we doing here statistics on a one-surgeon sample size?
  - Ensorceled 6y ago
    Where is the "one surgeon" sample size?
    - soco 6y ago
      It's about the success of surgery on that surgeon's birthday, and calculating the implications of switching the surgery types etc etc, while in a real world situation you'd just use the other surgeon - which hopefully has another birthday. I agree there's gonna be some smaller effect even then, but less and less the more surgeons you have and the more randomly distributed their birthdays are.
- FabHK 6y ago
  > 1) "23% more likely to die" seems _huge_, but it applies to an already very small chance. The mortality rate just goes from 5.6% to 7%. Using this logic, moving from 0.1% mortality rate to 0.3% would mean "you are 3 times more likely to die". But that is indeed precisely what it means. The 737 MAX might have increased the accident rate from 1 in a million to 3 in a million, and that would have been a tripling. That is not sensationalistic. > 3) Where are the confidence intervals? In the paper: "(7.2% v 5.6%; adjusted difference 1.6%, 95% confidence interval 0.4% to 2.8%; P=0.01)"
ericpauley 6y ago
Simpson's paradox: https://en.m.wikipedia.org/wiki/Simpson%27s_paradox https://en.m.wikipedia.org/wiki/Simpson%27s_paradox
- La1n 6y ago
  I think it'd be more accurate to describe this as suvival bias, where the worse cases "survive" (i.e. they get to be done on that day).
WarOnPrivacy 6y ago
> If this is fairly standard practice, then an afternoon birthday surgery would be an emergency situation and, hence, more deadly. As pointed out by jlebar, this is controlled for by comparing similar emergency surgeries. "The patients were all Medicare beneficiaries aged 65 to 99. They had all undergone one of 17 common emergency surgical procedures between 2011 and 2014."
- wittyreference 6y ago
  There are emergencies, and there are EMERGENCIES. The former can often wait 24 hours; the latter cannot wait at all. Medicare data does not capture that at all - it only captures the categorical, "surgery type." e.g., someone has a run of the mill cholecystitis that needs to come out. It can go when there's an opening in the surgical schedule, or tomorrow morning. That's an "emergency" - it came in through the ED, wasn't elective. Then there's the person w/ chole that looks septic and you're afraid they're going to perf or already have. That person is going to the OR now. Under Medicare coding, both of those are lap choles, CPT 47562. This doesn't control for that at all, except in the broadest of ways. Also, a 65yo surgical candidate and a 99yo surgical candidate are wildly different. 99yo isn't going under the knife for anything other than immediate threat of death or unendurable pain. In the lap chole example above, I'm going with a trial of abx in the 99yo unless he's absolutely about to perf; 65yo, sure, let's take the gallbladder out - once he's progressed to sx chole, odds are really good it'll have to come out within the next two years. I think most surgeons would rather do it at 65 than 67. Looking at the 2x2 of 65, 99, emergency, and EMERGENCY, you capture an incredibly large variety of severity and risk.
misiti3780 6y ago
Not exactly the same by similar: My father is a surgeon at a small hospital and my mother just got her hip replaced a few weeks ago (at a different, larger city hospital) and the first thing he insisted on was she was scheduled as the first patient of the day.
giantg2 6y ago
My father is a physician. He always recommends that if you are getting a test done, try to schedule it for the middle of the week and not near a holiday. It seems the lab techs make more mistakes on Fridays, weekends, etc. Just his anecdotal experience.

jlebar 6y ago

> If this is fairly standard practice, then an afternoon birthday surgery would be an emergency situation and, hence, more deadly. TFA says they're only counting emergency surgeries, to avoid exactly this bias.

UncleMeat 6y ago
This is the most frustrating pattern in online discussion of science. A post title presents a conclusion, then the top comment proposes some alternative cause of the conclusion or some hypothesized methodological weakness in the research, then readers assume that the research is bad. Often, the exact specific criticism appears directly in the paper because the researchers thought of that too.
- trisiak 6y ago
  No reason to be frustrated. Things are almost never right or wrong, particularly in complex science. In this case, based on another comment above about "emergency procedure" having multitude of meanings, you're most likely wrong in that the paper has a rebuttal to the top post. The hypothesis then, is that the actual urgency of surgeries is not controlled precisely enough to state that they cannot affect the measurement.
  - UncleMeat 6y ago
    From the sibling comment. > The major threat to the internal validity of our findings is that surgeons may selectively operate on sicker and more complex patients on their birthday, perhaps because those patients cannot have their procedures delayed. However, this is unlikely to explain our findings because we found that patients who underwent surgery on the surgeon’s birthday were similar in all observable characteristics to patients who underwent surgery on other days. Furthermore, severity of illness as measured by predicted mortality, and the number of procedures performed per surgeon, also did not differ based on whether a surgery occurred on a surgeon’s birthday compared with other days. > we found that patients who underwent surgery on the surgeon’s birthday were __similar in all observable characteristics__ to patients who underwent surgery on other days
- FabHK 6y ago
  > Often, the exact specific criticism appears directly in the paper because the researchers thought of that too. From the paper: "The major threat to the internal validity of our findings is that surgeons may selectively operate on sicker and more complex patients on their birthday, perhaps because those patients cannot have their procedures delayed. However, this is unlikely to explain our findings because we found that patients who underwent surgery on the surgeon’s birthday were similar in all observable characteristics to patients who underwent surgery on other days. Furthermore, severity of illness as measured by predicted mortality, and the number of procedures performed per surgeon, also did not differ based on whether a surgery occurred on a surgeon’s birthday compared with other days."

colonwqbang 6y ago

This is a beautiful conjecture! The problem is amusingly circular. Even if you reject the conjure in parent comment, you will be tempted to reduce the number of birthday surgeries due to the increased mortality. This will mean that birthday surgeries are only done in even more desperate circumstances which of course will increase the risk. So mitigation of this problem will lead to the percentage increasing even more! Actually, it turns out that it is possibly better if the percentage is high!

Ensorceled 6y ago
Yes, it does really mean you need to dig into actual causation or the law of unintended consequences will bite you in the ass.
faeyanpiraat 6y ago
I do not completely understand your points. Shouldn't hospitals have multiple surgeons? If one of them is on vacation, the other one does the work, and vice versa?
- Galanwe 6y ago
  I don't think surgeons are fongible assets. There is a lot of planning and study taking place before a complex operation. Not to mention most surgeons have specialties.
  - watwut 6y ago
    The long term plans and studied for surgeries can be moved one day forward or backward basically by definition.
    - travmatt 6y ago
      Except if something changes suddenly and surgery is suddenly needed - that’s what makes it an emergency.
  - daniellarusso 6y ago

Galanwe 6y ago

> If this is fairly standard practice, then an afternoon birthday surgery would be an emergency situation and, hence, more deadly This is spot on. The causality can be both ways. Note that it would be interesting to dig into what is really computed here, because the whole wording seem intentionally sensationalistic. 1) "23% more likely to die" seems _huge_, but it applies to an already very small chance. The mortality rate just goes from 5.6% to 7%. Using this logic, moving from 0.1% mortality rate to 0.3% would mean "you are 3 times more likely to die". 2) Comparing mortality rates only make sense if the distribution of operation complexity are identical for these days. As the parent post suggest, it seems very likely that low complexity operations are postponed after a surgeons birthday. 3) Where are the confidence intervals? I refuse to even consider looking at a statistics if error boundaries and significance metrics are not provided. That may very well all be provided in the underlying paper, but the article itself does not really discuss these points.

soco 6y ago
Aren't we doing here statistics on a one-surgeon sample size?
- Ensorceled 6y ago
  Where is the "one surgeon" sample size?
  - soco 6y ago
    It's about the success of surgery on that surgeon's birthday, and calculating the implications of switching the surgery types etc etc, while in a real world situation you'd just use the other surgeon - which hopefully has another birthday. I agree there's gonna be some smaller effect even then, but less and less the more surgeons you have and the more randomly distributed their birthdays are.
FabHK 6y ago
> 1) "23% more likely to die" seems _huge_, but it applies to an already very small chance. The mortality rate just goes from 5.6% to 7%. Using this logic, moving from 0.1% mortality rate to 0.3% would mean "you are 3 times more likely to die". But that is indeed precisely what it means. The 737 MAX might have increased the accident rate from 1 in a million to 3 in a million, and that would have been a tripling. That is not sensationalistic. > 3) Where are the confidence intervals? In the paper: "(7.2% v 5.6%; adjusted difference 1.6%, 95% confidence interval 0.4% to 2.8%; P=0.01)"

ericpauley 6y ago

Simpson's paradox: https://en.m.wikipedia.org/wiki/Simpson%27s_paradox https://en.m.wikipedia.org/wiki/Simpson%27s_paradox

La1n 6y ago
I think it'd be more accurate to describe this as suvival bias, where the worse cases "survive" (i.e. they get to be done on that day).

WarOnPrivacy 6y ago

> If this is fairly standard practice, then an afternoon birthday surgery would be an emergency situation and, hence, more deadly. As pointed out by jlebar, this is controlled for by comparing similar emergency surgeries. "The patients were all Medicare beneficiaries aged 65 to 99. They had all undergone one of 17 common emergency surgical procedures between 2011 and 2014."

wittyreference 6y ago
There are emergencies, and there are EMERGENCIES. The former can often wait 24 hours; the latter cannot wait at all. Medicare data does not capture that at all - it only captures the categorical, "surgery type." e.g., someone has a run of the mill cholecystitis that needs to come out. It can go when there's an opening in the surgical schedule, or tomorrow morning. That's an "emergency" - it came in through the ED, wasn't elective. Then there's the person w/ chole that looks septic and you're afraid they're going to perf or already have. That person is going to the OR now. Under Medicare coding, both of those are lap choles, CPT 47562. This doesn't control for that at all, except in the broadest of ways. Also, a 65yo surgical candidate and a 99yo surgical candidate are wildly different. 99yo isn't going under the knife for anything other than immediate threat of death or unendurable pain. In the lap chole example above, I'm going with a trial of abx in the 99yo unless he's absolutely about to perf; 65yo, sure, let's take the gallbladder out - once he's progressed to sx chole, odds are really good it'll have to come out within the next two years. I think most surgeons would rather do it at 65 than 67. Looking at the 2x2 of 65, 99, emergency, and EMERGENCY, you capture an incredibly large variety of severity and risk.

misiti3780 6y ago

Not exactly the same by similar: My father is a surgeon at a small hospital and my mother just got her hip replaced a few weeks ago (at a different, larger city hospital) and the first thing he insisted on was she was scheduled as the first patient of the day.

giantg2 6y ago

My father is a physician. He always recommends that if you are getting a test done, try to schedule it for the middle of the week and not near a holiday. It seems the lab techs make more mistakes on Fridays, weekends, etc. Just his anecdotal experience.