Swanpride wrote:

This is still a TV show, not a documentary about gun shot wounds, and the meta discussed it as such. It mostly illustrates that if we assume that the writers wanted the "surgery" situation and then asked a medical expert what place of the body would be a believable target, this would be the point they would come up with, for various reasons. That this can go wrong, really badly, in real life should be pretty clear - in fact the meta theorizes that it DID go wrong right there in the show, because Mary hit something she didn't intend to hit.

I say it one last time (because we are going in circles here): Mary is a trained assassin who is standing directly in front of Sherlock. She has the pick to shot him either in the heart or the head - and that she knows how to do those shots is a given. Even a hunter knows how to do an ideal kill shot, because the flesh tastes better if the prey has no time to feel fear. The theory that she was trying to derail John is not holding up, because in this case she could simply shot Sherlock in the abdomen, which would kill him for sure, too, just slower. But the spot she did pick was the liver. The one spot which has a very high survival rate. So why should she shot Sherlock in this place if she didn't want to give him a chance for survival?

I really don't see any reason why Sherlock should lie for her. Why should he encourage John to forgive and life with someone who might try to murder him? He even goes so far to tell John that he should trust Mary while breaking down...those could be his last words, but he insists on saying them.

I am trying hard to be polite about the anonymous medic who wrote the meta you cite, but even a non acute trauma specialist knows that cherry picking one piece of research on gunshot liver injuries when Pubmed is knee deep in reports of much larger studies with much higher mortality rates goes beyond the bounds of acceptable scribbling and comes exceedingly close to deliberate misrepresentation.

In other words, anyone idiotic enough to rely on a small case series whilst ignoring much larger ones is allowing sentiment to affect their judgement. It is unsurprising that other people are pointing out it is nonsense; the reason for this is that it is nonsense.

It is equally nonsensical to suggest that someone bleeding out, as Sherlock was, is in any fit state to judge who should be trusted and who should not. In order for the brain to function it needs oxygen; someone bleeding out is highly deficient in oxygen, and thus not exactly at their intellectual peak...

 

Actually,  I have been watching Due South, lured by one of our fellow posters who does not even like the show herself, who put me onto the fanfic, and when 'I'd run out of fanfic, I went to find the episodes,  and the rest is history.

We really do have some amazingly kind and helpful people on this forum; I thank you kindly 

belis wrote:

Willow wrote:

I am trying hard to be polite about the anonymous medic who wrote the meta you cite, but even a non acute trauma specialist knows that cherry picking one piece of research on gunshot liver injuries when Pubmed is knee deep in reports of much larger studies with much higher mortality rates goes beyond the bounds of acceptable scribbling and comes exceedingly close to deliberate misrepresentation.

In other words, anyone idiotic enough to rely on a small case series whilst ignoring much larger ones is allowing sentiment to affect their judgement. It is unsurprising that other people are pointing out it is nonsense; the reason for this is that it is nonsense.

I tried to search litrature on this subject systematically and so far I didn't have much sucess. Combined search of two detabases uncovered a grand total of 3 articles, all being case series. The article quoted by the author is the largest case series I managed to find so far (153 people over 10 years is not bad). For obvious reasons there aren't going to be any randomised control trials so the best we can hope in terms of evidence is case series and maybe a cohort study.

It seems that you had much more like with Pubmed. Could you point me towards any of the larger studies you found?

Well, the one which obviously appeals, not least because of the name which seems distinctly Sherlockian:

'Gunshot injuries of the liver: the Baragwanath experience.
Degiannis E1, Levy RD, Velmahos GC, Mokoena T, Daponte A, Saadia R.
Author information

Abstract
BACKGROUND:
This study comprised 304 patients with gunshot injuries of the liver, many of which from high-velocity firearms. The purpose of this study is to evaluate our management policy in gunshot injuries of the liver in light of our recent wider experience.'

This is double the number of cases in the study relied on by the meta writer; it really does not make any sense to choose the small case series when you have one twice as large with different results.

There is also the blindingly obvious fact that case series can only cover the number of people who survived sufficiently long to reach the hospital and be treated. I would suggest that no one in their right minds assumes that all patients shot in the liver survive until they reach hospitals    though obviously I do not wish to trespass on your territory

 

Last edited by Willow (February 28, 2014 9:14 am)

lil, you're right, agreeing is what she mostly does in this whole scene. She doesn't really volunteer any information herself, it's Sherlock who gives information and does most of the talking. And for quite a long while Mary is just standing there, watching and saying nothing. And eventually she is agreeing with Sherlock that yes, she is the way she is because John chose her. Maaahhh! Good for her that Sherlock gave such a convenient explanation... 

lil wrote:

Whats really funny here is Marys reactions as Sherlock gives his..she saved me..mixed messages bleh @ John.
Marys wide surprised eyes..her dropped jaw..her gobsmacked face..the moments of confusion..shaking her head in disbelief as she agrees with Sherlock in a errr yeah what he said way...
It's obviously the first time she has ever considered..heard anything like this excuse.
If you have ever caught two children doing something wrong..and one makes up a crazy it wasn't us excuse while the other nods amazed along....agreeing and hoping to get off.
Well thats how that scene goes.

Yep; you've got it. 
 

Willow wrote:

lil wrote:

Whats really funny here is Marys reactions as Sherlock gives his..she saved me..mixed messages bleh @ John.
Marys wide surprised eyes..her dropped jaw..her gobsmacked face..the moments of confusion..shaking her head in disbelief as she agrees with Sherlock in a errr yeah what he said way...
It's obviously the first time she has ever considered..heard anything like this excuse.
If you have ever caught two children doing something wrong..and one makes up a crazy it wasn't us excuse while the other nods amazed along....agreeing and hoping to get off.
Well thats how that scene goes.

Yep; you've got it.
 

A little bit like the smoking scene at Christmas? Only that Sherlock blamed Mycroft instead of defending Mary. But nevertheless a lie?

Swanpride wrote:

@Willow So perhaps you can tell me how many of the patients died according to the larger study? Perhaps I read it wrong, but since every per cent number we get refers specifically to a higher level of injury, and we don't know how many of the victims had this level of injury (for all we know, they are talking only about 20 patients there while everyone else was level I or II), we could be talking about one single patient which actually died.
Never mind that the large study confirmed at least one thing: The largest problem with liver injuries is the bleeding. This concurs with the smaller study and with what was shown during the show.

And since Sherlock got hospital treatment and Mary made sure that he got it, I really don't see how people who don't get any figure into this.

You haven't bothered to do even the most basic research on the hospital in question; if you had then you would know that it is the largest acute hospital in the world, with almost 3000 beds, and that 50% of the patients had stab or gunshot wounds.

In other words, they know their gunshot wounds better than anywhere other than a war zone, and indeed, they invite would be trauma surgeons to do their electives there, on the grounds that they will see vast numbers of cases which could only be matched in a war zone.

You don't seem to be interested in doing any research, and you don't seem interested in anything other than trying to claim that Mary was doing 'surgery' saving Sherlock's life.

We don't know that Mary ensured that Sherlock got hospital treatment; as the author of the more accurate meta notes the screenshots show CAM using what looks like a phone. As I have noted, a billionaire requesting an ambulance would be likely to get one faster than an anonymous caller; 999 gets plenty of hoax calls, which is why all messages are recorded, and from time to time legal action is taken against people making those calls.

And no one in London imagines that you could rely on an ambulance turning up in precisely 8 minutes; there's this thing called traffic which plays havoc with average numbers. Mary certainly attempted at the end to prevent CAM taking effective action to save Sherlock's life by pistol whipping him; we have things called air ambulances which are used where possible for really urgent cases. The Royal London, which is the major trauma centre, has a helipad, and CAM's headquarters has a helipad; it's not difficult to connect the dots to see how CAM could have got him to hospital really quickly had he not been pistol whipped by Mary.

If you really are unable to grasp that it is impossible to estimate mortality rates by looking only at people who survive long enough to get to a hospital, then I can't think of any better way of explaining it to you. It is a very simple and straightforward point...
 

My apologies; I am in the process of trying to strip Office off my computer and reinstall it so that it doesn't immediately crash whenever I try to open Word. I really should know better than to try grappling with Microsoft and posting at the same time...

Swanpride wrote:

Yeah, but would be believe Mary anything she says? It would just sound like a feeble excuse. Sherlock deducing it makes it way more official than the world of a lying ex-assassin.

Makes sense, because (obviously) Mary is a lying ex ?, really?  Assassin!

Willow wrote:

'Gunshot injuries of the liver: the Baragwanath experience.
Degiannis E1, Levy RD, Velmahos GC, Mokoena T, Daponte A, Saadia R.
Author information

Abstract
BACKGROUND:
This study comprised 304 patients with gunshot injuries of the liver, many of which from high-velocity firearms. The purpose of this study is to evaluate our management policy in gunshot injuries of the liver in light of our recent wider experience.'

This is double the number of cases in the study relied on by the meta writer; it really does not make any sense to choose the small case series when you have one twice as large with different results.

There is also the blindingly obvious fact that case series can only cover the number of people who survived sufficiently long to reach the hospital and be treated. I would suggest that no one in their right minds assumes that all patients shot in the liver survive until they reach hospitals though obviously I do not wish to trespass on your territory  

I can’t argue with the fact that neither of the studies takes into account people who expire before reaching the hospital. It’s an important limitation, which illustrates the challenges of trying to practice evidence based medicine. It’s not that easy to find studies that apply perfectly to the population we are interested in.

There is however an important caveat. Wellingtongoose uses the 8% statistic to compare the mortality rates between liver and thoracic injuries, not to talk about mortality in absolute terms.

‘The mortality rate for the entire group attributed to liver injuries was 8% (12). Thus the chances of surviving a shot to the liver are 92 percent. Compare this to a thoracic gunshot wound which has a mortality rate of around 20-30%.’
 Consequently we can forget about people who die outside of the hospital as the same confounder is going to apply to both groups of interest (liver and thoracic injury).
 
Why did he choose to reference this paper and not the larger study? I suspect the main reason is that to obtain the mortality rate from Baragwanath study you need to do some leg work. The abstract doesn’t provide that information. To read the full article you either need to pay or be a subscriber. The

When you get hold of the full article some calculations are required.

Out of the total sample of 304 patients 19 died directly from their liver injuries giving a mortality rate of 6.2 %. That’s lower than figure quoted by Wellingtongoose. Majority of patients (241) ended up with grade I-III injuries and most of them didn’t need operating on. Only 4 of those patients died as a direct result of the trauma to the liver.

So in fact the larger study does confirm that liver is not such a bad place to be shot at in a grand scale of things.
 

Last edited by belis (February 28, 2014 6:44 pm)