Sure - the author of the Telegraph article states the following:
“Yet experts say there are major problems in this approach. To begin with, it is unsurprising that Letby is present on all these occasions given that these are the cases for which she is under investigation.
The chart excludes deaths and collapses which occurred at the neonatal unit when she was either not present or where there was little evidence to suggest she was responsible.”
Now, neither you, nor I, nor, it seems, the prosecution, defence, judge and jury have the full data set of all shifts when a baby collapsed or died.
The shift table also doesn’t specify whether a collapse or death occurred on that shift.
I’ve read back through previous articles and can confirm that Dr Brearey (Neonatal Consultant at CoC) was the person who compiled that shift table data set.
I strongly suspect his motivation for doing so was to identify whether there was a colleague whose presence on the ward correlated with increased collapses or deaths.
In short - it’s likely he sat down at an Excel spreadsheet with the hypothesis “A staff member may be responsible for these events. Who is the most likely candidate?”.
Secondly, let’s assume Dr Brearey DID include every single episode of collapse/death… and every time, Letby was there.
25 such events over a 13 month period (June 2015 - June 2016) would be a VERY small number of adverse events for an understaffed, poorly equipped ward admitting:
- Seriously premature infants
- Seriously underweight infants
- Infants requiring ventilation
- Infants with complex illness (e.g. necrotising enterocolitis)
In addition, the Telegraph article also acknowledges instances of adverse medical accidents in the care of some of the babies, such as the incorrect placement of umbilical venous catheters (UVCs) by doctors, which can lead to blood clots.
In fact, the 2016 RCPHC review recommended the Trust revise procedures around UVC placement. In 2021, NICE guidelines were given a huge overhaul to acknowledge that incorrect UVC placement was dangerous and advice on correct placement methods was updated to improve safety.
In another infant, doctors tried multiple times to insert a breathing tube. In the end, they had to request a doctor attend from a neighbouring hospital to attempt intubation. That doctor successfully intubated the baby on first attempt. That baby had a long wait for proper ventilation and it raises questions about the skills of the doctors on the unit.
My point is - NICU is a ward in which adverse events or collapse are likely to be high.
It is therefore highly unlikely that the 25 instances Dr Brearey submitted on the shift table were the only episodes in which adverse events or collapse occurred, irrespective of death.
In short, the data only includes instances of collapse/death in which Letby is the common factor.
It could be that Dr Brearey initially compiled a massive table of data with every event detailed.
It could be that he saw slightly more crosses for Letby’s column.
It could be that he then filtered the data to show only Letby’s shifts…
… and bingo! You have the nurse caught red handed!
… or do you have the nurse working a lot of shifts who looked after the majority of very poorly babies more likely to die of natural causes?
We just don’t know.
I sincerely hope the defence requests all of the data and arranges a statistical analysis by a professional so that it can be submitted as new evidence to the Criminal Cases Review Commission.
I agree the following points:
- The shift table does not indicate deaths vs collapse
- The shift table does not indicate if all the babies included (A-Q) died with Letby present
- The shift table does not indicate all additional adverse events/ collapses/deaths that occurred when Letby was not on duty
Once again, we cannot conclude that Letby was the common denominator when collapse/death occurred, because:
- The data set is incomplete
- It does not factor in very important variables such as whether Letby looked after the most poorly babies (with the highest probability of natural death due to premature Illness) for the largest number of shifts compared to other nurses on the unit
I cannot say either way if Dr Brearey was well intentioned or conscious of his own bias.
Doctors generally have a decent grasp of complex statistic - for example, a lot of medical research studies will use statistics to calculate something called a p value. If it’s less than <0.005, it tells you that the treatment (e.g. a drug) works. It rules out that the patient didn’t just get better by pure chance alone. This is known as calculating statistical significance.
In short, doctors know exactly how to make sure their data is statistically significant!
In fact… making that statement makes me flabbergasted all the more…
Why didn’t Dr Brearey enter his shift data into a simple statistical calculation tool to determine if Letby was involved in more cases simply by chance or not?!
If she had a statistically significant p value of >0.005, perhaps we wouldn’t be sitting here debating whether a miscarriage of justice has taken place or not...