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Experts warn Letby inquiry of misreading stats to explain 'suspicious' deaths

thejusticegap.com

21–30 of 93 posts

Re: Experts warn Letby inquiry of misreading stats to explain 'suspicious' deaths

#21
post #18

Earlier quoted context omitted.

[deletia, cuz I misread the article.]

No it wasn't. See my sibling comment in this thread. At worst, it alerted authorities to there potentially being foul play. Her actual conviction was based on other factors.

Thanks for clarification. That's very reassuring.

Re: Experts warn Letby inquiry of misreading stats to explain 'suspicious' deaths

#22
post #2

Anybody who closely followed this case who could identify for the readers here any direct evidence of these crimes, or should we read this article to imply Lucy herself might be innocent?

There were various postmortem findings described as anomalous.

Child F had a bloodwork which indicated that someone gave them a large amount of insulin.

Child D’s post mortem X-ray is said to show air injected into their blood vessels.

Child L also had insulin in their blood.

I’m not an expert so I can’t say for certain how strong these evidence are. Also my understanding that while these are evidence that a crime happened, they do not tie Lucy directly to the crime. The evidence for that is circumstatial, mainly that she was the only one on duty for all the collapses said to be suspicious.

Re: Experts warn Letby inquiry of misreading stats to explain 'suspicious' deaths

#23
post #11

While the statisticians are right to be cautious about clusters of deaths => serial killer, we also have to remember that a 9 month trial presented lots of evidence to a jury, they deliberated for over a week, and returned seven guilty verdicts. Unless you were also sitting at that trial or have read every line of court transcript, it would be very unwise to start claiming there's a miscarriage of justice.

Those arguments included that the suspicious deaths all lined up perfectly with Lucy Letby's shifts, that she was often caught interacting with those babies when she had been instructed not to, and that when she was taken off the ward the deaths instantly stopped. That is a level of causality checking far stronger than most Bayesian analyses.

And she took home documents from several of those patients, which she'd have no ordinary reason to have fished out of the trash.

Re: Experts warn Letby inquiry of misreading stats to explain 'suspicious' deaths

#24
post #3

Quite right. I remember Ben Goldacre's book Bad Science documenting a few examples. I hope these are the same examples raised in the letter, because otherwise a lot of miscarriage of justice has happened in the UK. What I remember from the book is entirely innocent people jailed because the wrong statistical question was asked. IIRC along the lines of two deaths, and the question asked was what is the chance of this…

>otherwise a lot of miscarriage of justice has happened in the UK.

Depends on 'a lot', but I rather suspect there will be/ will have been fewer, now cops have to use cameras, but yes - a lot of miscarriages of justice has happened in the UK. And every other country.

Re: Experts warn Letby inquiry of misreading stats to explain 'suspicious' deaths

#25

Earlier quoted context omitted.

Those arguments included that the suspicious deaths all lined up perfectly with Lucy Letby's shifts, that she was often caught interacting with those babies when she had been instructed not to, and that when she was taken off the ward the deaths instantly stopped. That is a level of causality checking far stronger than most Bayesian analyses.

And she took home documents from several of those patients, which she'd have no ordinary reason to have fished out of the trash.

And the little old thing that she wrote "I killed them on purpose" on a post-it-note at her house.

Re: Experts warn Letby inquiry of misreading stats to explain 'suspicious' deaths

#26

Earlier quoted context omitted.

Those arguments included that the suspicious deaths all lined up perfectly with Lucy Letby's shifts, that she was often caught interacting with those babies when she had been instructed not to, and that when she was taken off the ward the deaths instantly stopped. That is a level of causality checking far stronger than most Bayesian analyses.

And she took home documents from several of those patients, which she'd have no ordinary reason to have fished out of the trash.

And she had post-it notes at home where she had written "I killed them on purpose."...

Re: Experts warn Letby inquiry of misreading stats to explain 'suspicious' deaths

#27
post #25

Earlier quoted context omitted.

And she took home documents from several of those patients, which she'd have no ordinary reason to have fished out of the trash.

And the little old thing that she wrote "I killed them on purpose" on a post-it-note at her house.

Ah jinx!

Re: Experts warn Letby inquiry of misreading stats to explain 'suspicious' deaths

#28
post #11

While the statisticians are right to be cautious about clusters of deaths => serial killer, we also have to remember that a 9 month trial presented lots of evidence to a jury, they deliberated for over a week, and returned seven guilty verdicts. Unless you were also sitting at that trial or have read every line of court transcript, it would be very unwise to start claiming there's a miscarriage of justice.

I suppose, but it wouldn't be the first time a judge or jury was swayed by dubious statistics.

At least that is exactly what happened to Lucia de B [1] (which they mention in the article), which at first glance looks eerily similar.

[1]: https://en.m.wikipedia.org/wiki/Lucia_de_Berk

Re: Experts warn Letby inquiry of misreading stats to explain 'suspicious' deaths

#29
post #11

While the statisticians are right to be cautious about clusters of deaths => serial killer, we also have to remember that a 9 month trial presented lots of evidence to a jury, they deliberated for over a week, and returned seven guilty verdicts. Unless you were also sitting at that trial or have read every line of court transcript, it would be very unwise to start claiming there's a miscarriage of justice.

I suppose, but it wouldn't be the first time a judge or jury was swayed by dubious statistics. At least that is exactly what happened to Lucia de B [1] (which they mention in the article), which at first glance looks eerily similar. [1]: https://en.m.wikipedia.org/wiki/Lucia_de_Berk

The difference is that statistics were used in de Berk's prosecution, but were not used in Letby's prosecution.

Re: Experts warn Letby inquiry of misreading stats to explain 'suspicious' deaths

#30
There seems to be some (understandable) confusion in some of the comments about what the article here is reporting which isn't helped by a lack of clarity in it or the underlying Guardian piece, possibly in each case intended to push their own agendas.

There appears to be an interpretation here by some of a potentially unsafe verdict due to misreading of statistics in her conviction - which has certainly happened in the past in other cases including those mentioned.

The expert input here though is intended as advice for the inquiry into what went wrong at the places Letby worked to lessen the risk of it happening again.

That necessarily includes qualified and responsible analyses of statistics, which will also have the benefit of increasing protection and support of staff as well as improving safety generally.

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