True, the example I gave didn’t specifically illustrate any particular bias. However, I think there was a little bit of anchoring and confirmation bias involved. He expected to see an alcohol-OD patient. He saw a lot of symptoms that fit the diagnosis. I don’t know her specific case, if there were symptoms he missed or disregarded, but it’s probably a safe assumption.
The thing is—yes, alcoholism is the most likely hypothesis. However, anyone could say that alcoholism was the most likely hypothesis; it’s the doctor’s job to also consider the unlikely ones (especially the potentially fatal ones). That concept gets drilled into our head constantly over here. You’re right—“pretending it’s the worst-case-scenario” is wrong, but seriously considering the worst-case scenario is essential. A CT would have been wrong, but there are other tests (i.e. finding problems with one side of the body but not the other is a dead-giveaway).
I don’t want to rag on this doc—this patient was coming from a party, and I don’t know if her specific case could easily be distinguished from excessive alcohol use. But it did help drive home the importance to keep my eyes open.
Also, is there some sort of reasonable threshold? It’s not as though strokes are extremely rare, though they are rare compared to getting drunk on Friday night.
Good question, To make a list of criteria for what is “reasonable threshold” for each disease, given each symptom, and each test, such a thing would probably be more trouble than it’s worth for the simple in-the-room tests, but I’m sure they exist for expensive/harmful things like biopsies or CT scans. In this case, I think the presentation exceeds the threshold to consider a stroke, but not enough to do costly tests.
In general, we’re drilled with the general algorithm:
1) a long list of “triggers” that says, “if you see this/these symptom(s), you should immediately put dangerous diseases X, Y, and Z on your differential.” e.g. disorientation and slurred speech, the word “stroke” should AT LEAST enter your mind temporarily.
2) Then, rule-out X Y and Z with cheap and easy tests, which is usually something like:
Y and Z are unlikely because he lacks (certain other traits or symptoms)
I can rule out X with a quick check, like a 2-minute neurological exam.
3) Think horses, not zebras.
True, the example I gave didn’t specifically illustrate any particular bias. However, I think there was a little bit of anchoring and confirmation bias involved. He expected to see an alcohol-OD patient. He saw a lot of symptoms that fit the diagnosis. I don’t know her specific case, if there were symptoms he missed or disregarded, but it’s probably a safe assumption.
The thing is—yes, alcoholism is the most likely hypothesis. However, anyone could say that alcoholism was the most likely hypothesis; it’s the doctor’s job to also consider the unlikely ones (especially the potentially fatal ones). That concept gets drilled into our head constantly over here. You’re right—“pretending it’s the worst-case-scenario” is wrong, but seriously considering the worst-case scenario is essential. A CT would have been wrong, but there are other tests (i.e. finding problems with one side of the body but not the other is a dead-giveaway).
I don’t want to rag on this doc—this patient was coming from a party, and I don’t know if her specific case could easily be distinguished from excessive alcohol use. But it did help drive home the importance to keep my eyes open.
Also, is there some sort of reasonable threshold? It’s not as though strokes are extremely rare, though they are rare compared to getting drunk on Friday night.
Good question, To make a list of criteria for what is “reasonable threshold” for each disease, given each symptom, and each test, such a thing would probably be more trouble than it’s worth for the simple in-the-room tests, but I’m sure they exist for expensive/harmful things like biopsies or CT scans. In this case, I think the presentation exceeds the threshold to consider a stroke, but not enough to do costly tests.
In general, we’re drilled with the general algorithm: 1) a long list of “triggers” that says, “if you see this/these symptom(s), you should immediately put dangerous diseases X, Y, and Z on your differential.” e.g. disorientation and slurred speech, the word “stroke” should AT LEAST enter your mind temporarily. 2) Then, rule-out X Y and Z with cheap and easy tests, which is usually something like: Y and Z are unlikely because he lacks (certain other traits or symptoms) I can rule out X with a quick check, like a 2-minute neurological exam. 3) Think horses, not zebras.