Safety Critical Industry – Are you different to the NHS (Lucy Letby)

At the very least it puts her at the scene of the crimes.

Sure, but y’know, she worked there, it’s not a massive surprise. As others have pointed out, the expert defence witnesses offered enough of an explanation to doubt whether crimes were committed.

think the main question is, are we sure crimes were committed?

yes – 100%

yes – 100%

OK, the next question is, are you 100% certain about the exact number of crimes that were committed?

The jury were.

Ignorance, not casting doubt on peoples assertions but the 1/73m cot death thing; is there a link or can someone explain simply why the claim is false. I’m not a statistician so I’m sure the answer is statistics; I (thought I) understand probability though.

https://www.stat20.org/3-probability/02-cond-prob-indep/notes#:~:text=Professor%20Roy%20Meadow%20claimed%20that,the%20two%20events%20as%20independent.

I think part of the problem is that people are much more likely to accept an explanation they can easily understand than one that they need a lecture and at least 20 minutes with a pencil and paper to figure out.

For me, one of the most alarming thing in that “shifting the data” post is not the dodgy stats, but this assertion:

Human rights and criminal defence Barrister Mark McDonald states, “It is almost impossible to get defence experts in the UK to give evidence in cases involving children, they are too scared. You have to go overseas, usually to the US.”

 

OK, the next question is, are you 100% certain about the exact number of crimes that were committed?

No.

Human rights and criminal defence Barrister Mark McDonald states, “It is almost impossible to get defence experts in the UK to give evidence in cases involving children, they are too scared. You have to go overseas, usually to the US.”

The defence had experts ready to testify and chose not to call them.

“ At the very least it puts her at the scene of the crimes.”

Given that “crime” was defined as “untoward event that took place with Letby on duty” that’s an utterly meaningless statement.

She was there when she was there. So what? It’s not even evidence that there were any crimes at all, still less that she was guilty of any, let alone all of them.

The jury were misled by bogus evidence.

The spreadsheet alone is proof enough of that. Even after it’s been explained why it’s bogus there still seem to be people here who think it means something.

I don’t think we’ll be able to decide whether she’s guilty or not here.  I think it’s more a question of whether the case that was built looked convincing to the jury but once some of the details became public then others were able to look at it and say, ‘Wait a minute, you cherry picked that data.’

It did a good job of convincing the jury but unfortunately it also served to undermine public confidence in the conviction.

Of course, I’m sure there is more evidence but manipulating data is a major red flag.  Something the people who were prosecuting her should have known.

@theotherjonv

Ignorance, not casting doubt on peoples assertions but the 1/73m cot death thing; is there a link or can someone explain simply why the claim is false. I’m not a statistician so I’m sure the answer is statistics; I (thought I) understand probability though.

Some cot deaths are likely due to genetic abnormalities outside of current medical knowledge, therefore if you had one of those genetic abnormalities in your family, you could expect an increased risk of cot deaths. So having more than one unexplained death isn’t de facto evidence that it’s foul play.

She was there when she was there. So what? It’s not even evidence that there were any crimes at all,

No-one has suggested that her being at work is evidence of a crime. But you can guarantee that, if she was off-shift for every unexpected death during that period, she would not now be in prison.

The spreadsheet alone is proof enough of that. Even after it’s been explained why it’s bogus there still seem to be people here who think it means something.

The only deaths that were on there were the ones thought to be suspicious or unexpected. Happy for you to explain why unsupicious deaths should have been included.

Of course, I’m sure there is more evidence but manipulating data is a major red flag.  Something the people who were prosecuting her should have known.

Is that defamatory? 🙂 What data manipulation took place?

Guilty ? Personally I dont think so.

Sorry long winded explanations concerning feeding tubes or anything else I couldn’t comment on. Just feel this is a miscarriage of justice and its more likely poor consultants and a general poor practice over all.

All in a ward that has a natural high death rate due to the very poorly condition of the babies using it.

I wonder what the conviction rates were before they discovered sudden infant death syndrome was actually a thing. All convicted on strong medical evidence or professional evidence. Yup, on that score that had all the mothers down convicted as murderers.

Of course, I’m sure there is more evidence but manipulating data is a major red flag.  Something the people who were prosecuting her should have known.

Assuming that they understand that that is what they were doing. It’s possible that they were incompetent (with stats) and failed to realise that they were producing a chart of data that had already been filtered.

The only deaths that were on there were the ones thought to be suspicious or unexpected. Happy for you to explain why unsupicious deaths should have been included.

As far as I can tell, once you take away the deaths Letby was suspected of, you’re still left with 8 deaths.  That’s more than twice as many as the average (3.5).

I’m sure it’s possible she was responsible for more deaths than she was convicted of, but it still needs explaining.  Otherwise, like I said, it starts looking like the data is being manipulated and that is something that, quite rightly, makes people start asking a lot of questions.

The only deaths that were on there were the ones thought to be suspicious or unexpected. Happy for you to explain why unsupicious deaths should have been included.

Because of bias. The Excel was produced to demonstrate to the hospital malmanagement that Letby was “the missing link” to all the deaths that they thought were inexplicable, when statisticians have demonstrated that sometimes unexpected or random deaths are just what happens and there’s not a pattern.

Is that defamatory? 🙂 What data manipulation took place?

Defamatory?  Sounds like you’re fed up and want to shut down the discussion.

I’d say if you are showing that Letby was the only common factor by removing the 9 deaths (bearing in mind 3.5 is the average) where she wasn’t present that is manipulating the data.

https://www.scienceontrial.com/post/shifting-the-data

Any research or statistical exercise which approaches data with a preferred outcome in mind is vulnerable to bias, even if it is unconscious bias. That is why there is a duty for the prosecuting authorities not just to cherry pick data which supports their premise. Disregarding data which undermines your pet theory can leave you with something highly misleading.

The care of premature or dangerously ill neonates is fraught with unpredictable outcomes. Sometimes there are deaths which are hard to explain, babies can deteriorate quickly. Nevertheless, if you have a unit which has a spike in poor outcomes, that needs to be looked into in case there is a common factor.

In this case they had a spike, found that Letby was a common factor, but then worked back from that to see if any postmortem results from ‘her’ babies indicated foul play. Whether they did or not is a matter of argument, but the case continued.

I suspect that those who conducted the initial audit were not really looking for alternative reasons for the spike – were their cohort of babies sicker, smaller, more vulnerable? Were staffing levels adequate? Were conditions on the ward safe in other ways? It was much easier to find a common human factor than blame it on pure chance or systemic failures at the hospital.

Again, none of this rules out the possibility that Letby was the killer of one or more of the babies. But when you start digging into some of the really quite devious and inventive methods she was alleged to have used, and whether postmortem evidence supports these theories, it starts getting less and less plausible that things unfolded in quite the way that the prosecution suggested.

Because of bias. The Excel was produced to demonstrate to the hospital malmanagement that Letby was “the missing link” to all the deaths that they thought were inexplicable, when statisticians have demonstrated that sometimes unexpected or random deaths are just what happens and there’s not a pattern.

I understand much of the evidence is circumstantial – that being the case, her being present every time there was a unexpected or suspicious death is hugely relevant, surely. That unexpected or random deaths sometimes happen does not really inform this case – these were otherwise stable babies suffering sudden, unexpected and catastrophic collapse, often numerous times, many with air in their bodies where air should not be. If a natural explanation as to why this kept happening can be found, I’d be genuinely interested to hear it.

Defamatory?  Sounds like you’re fed up and want to shut down the discussion.

Pff, whatever. Defame away if you want to. 🙂

I’d say if you are showing that Letby was the only common factor by removing the 9 deaths (bearing in mind 3.5 is the average) where she wasn’t present that is manipulating the data.

What if those nine deaths were neither suspicious nor unexplained?

her being present every time there was a unexpected or suspicious death

My understanding is that is not what the chart shows.

It shows that she was present every time that there was an unexpected or suspicious death that they have decided to prosecute her for which is an entirely different thing.

If there are a number of excess deaths, and they’ve decided to only prosecute her for some of them because she was present for them then the chart means nothing. It’s circular logic.

That’s not what the Beeb reported.

“He [De Evans] added that the cases on the rota were there because, after reviewing all the deaths and collapses, he thought only they were suspicious or unexpected.

He said he had not known at that point that Letby had been on duty and this had only been revealed afterwards by Cheshire Police.

Dr Evans also made the point that none of those raising concerns had seen the patient notes.”

Anyway, clearly I’m wrong again so I’ll leave you all to it. 😉

her being present every time there was a unexpected or suspicious death is hugely relevant, surely.

Except, there were also unexpected deaths at which she was not present. The medical evidence that these were ‘otherwise stable babies’ has been challenged, and air can be introduced into the stomach as part of a resuscitation attempt. The whole air in the stomach thing is controversial, and the mechanism proposed by the prosecution has also been challenged.

These were all babies considered sick enough to be in PICU. Sure, you wouldn’t expect them to be dying en masse, but they are all at increased risk of collapse and sudden death. That’s why they’re there. And there are lots of factors in their quality of care which can influence their recovery, positively or negatively.

these were otherwise stable babies

According to the expert witness that her defence team decided not to call, many of the babies that the prosecution described as well, were in fact not very well at all. As others have said, we can’t decide guilt or otherwise, but it’s pretty clear from the post trial investigations that the jury heard just one side of the story, and that story was founded on – it turns out, at least highly contestable evidence.

What if those nine deaths were neither suspicious nor unexplained?

Well then that’s quite an increase from their usual 3-4 per year.

The problem with only including the suspicious deaths was that the alarm was first raised about Letby in July 2015:

https://www.theguardian.com/uk-news/ng-interactive/2023/aug/18/lucy-letby-timeline-attacks-babies-when-alarm-raised

For every death after that (and possibly from even earlier) if Letby is present then it is going to be suspicious.  Her presence automatically makes people suspicious. And then you make a chart showing that she was the only common factor in the suspicious deaths.

Of course she was.

Like I said, this proves nothing one way or the other.  As far as I know there was more evidence than just the ‘one common factor’ chart.

However, we’re thankfully at a stage now where any sign of manipulating numbers in these type of cases makes people immediately suspicious.  It could be she’s still very guilty but drawing a line under it is not the best way forward until all the extra deaths can be plausibly explained.

“ But you can guarantee that, if she was off-shift for every unexpected death during that period, she would not now be in prison.”

She was off shift for about half of them, so they decided that this half was just bad luck and the half that happened when she was there were all murders, every single one of them. They could have done exactly the same for any staff member and come up with a spreadsheet that looked just the same.

She was off shift for about half of them

Is that known?  There were nine deaths excluded from the chart, but is it known whether she was on or off shift for them?

She regularly did overtime as she was saving for a house, the unit was always short-staffed so plenty of work available.

You may find this interesting, from the blog of  Norman Fenton, Professor of Risk.

https://www.normanfenton.com/post/the-lucy-letby-trial-and-verdict-not-everybody-is-convinced-that-justice-was-done

A lot of babies in neonatal care aren’t necessarily “sick”, they have been born prematurely and need support to get them in a condition to be allowed home. The three main things they need is to be able to feed, breathe and retain heat. They might be in neonatal care due to being underweight and needing to effectively fatten up. A baby is pretty much fully developed way before being full term and spends a long time just putting weight on to make them more resilient at birth. The unit she worked on wasn’t for the most sick babies so I don’t think it would be normal for there to be a lot of deaths.

if expert medical witneses could have supported her case, they’d have called them.

Only if they were prepared to testify on her behalf. If not then once summons they would just no comment everything. The real problem is if it wasn’t her then what were the patients consultants doing and the consultant heading the unit? That bit seems to have been ignored with her conviction and I imagine the consultants don’t want looking at too closely. The reason everyone has a named consultant is because they are the one legally responsible for their patients care.

Puts rather a different spin on the notes she wrote:

https://www.theguardian.com/uk-news/article/2024/sep/03/i-am-evil-i-did-this-lucy-letbys-so-called-confessions-were-written-on-advice-of-counsellors

These were all babies considered sick enough to be in PICU.

A friend of mine worked as a nurse in special care baby unit. I asked her how she coped with the death of babies. Her response was that you celebrate the ones that get to go home because if your in that unit the odds are stacked against you in the first place

as someone who has been in an ITU with a patient going off there is no way at all that can be so.  Its simply not credible to not notice or not take any action

So coz it’s against training and your experience, the only other explanation is baby murder? That’s a bit of a leap.

It’s rigid thinking like that, that can scapegoat someone for the failings of an entire department rather than looking further. Maybe that’s the NHS way.

I’m not a statistician so I’m sure the answer is statistics

There is always a naive presumption that events are independent. So two rare events occurring in the same individual is simply related to the probability of each event squared. For some events, that are truly random, like winning the lottery, that premise is true. In the case of cot deaths the events may not be independent, and as mentioned, some underlying but unidentified risk factor may be present in both newborns that predispose. An analysis suggested that the true rate could be as high as 1/200 for two deaths when one had died already. For Sally Clark, it was not disclosed that the first child had a bacterial infection that may have hastened death. And hence the second death could have simply been chance. That rare events occur at all is simply the result of the huge number of trials (statistical term not legal event) – someone wins the lottery most weeks, despite the low individual probability.

For a paediatric ICU, one can calculate the risk of being on watch for any proportion of deaths, presuming they are independent. The closed form solution will be challenging, but the simulation shown in the link I provided shows that it is very easy to generate data that was used to convict. That “evidence” should be disregarded completely. In the dutch case discussed by the RSS, the miscarriage of justice was that no offence had been committed, the mortality rare for that unit at that time was an outlier.

Presume that the mortality rate for any shift is 10%, and there are 20 beds in the ICU. The probability that at least one baby dies in any shift is 1 – (1-0.1)^20 = 0.87 or 87%. And that is per shift. Without any wrongdoing. If shifts are staffed evenly, one can expect a distribution in number of shifts worked with a death. And it is possible that one poor nurse will be present for more than others. If you don’t adjusts for number of shifts worked, this is even more likely.

It’s not really a question of stats in this case. They had decided a few years previous to fit her up so along with a whispering campaign to undermine her confidence (hence the counselling!), they treated any incident while she was present as suspicious, while sweeping other events under the carpet. N years later, of course it looks like a bit more than coincidence.

The whole idea that she killed babies by pumping air into their stomachs is just nonsense. What an absurd suggestion.