The below from Peter Elston (a statistician) on X. There’s really no excuse for that ‘data’ having been presented as it was on Panorama tonight. It’s so irresponsible and they must know that by now.
“The mention in BBC’s Panorama of tube dislodgement statistics at Liverpool Women’s Hospital (LWH) when Lucy Letby worked there was misleading at best. The first public reference to the statistics came from Richard Baker KC's opening remarks at Thirlwall, though it was interesting that having mentioned them in his opening, completely uncorroborated, he made no further mention of them. In fact, nobody did. A letter was written by four experts (two consultant neonatologists including Dr Svilena Dimitrova, one consultant anaesthetist, and me) to LJ Thirlwall at the time complaining about Baker's remarks. The body of the letter is appended below. Sarah Knapton wrote about the letter an article in The Telegraph here -. archive.is/Nw0b0. Judith Moritz would have known about the letter but made no mention of it in today's Panorama. Poor journalism really, on top of everything else. Needless to say, LJ Thirlwall never replied to the letter.
This misleading statement was picked up by the media, and it is highly possible that by citing in articles the two numbers in the above without the necessary further explanation, distress has been caused to concerned parties. We do not find the assertion made above credible and are writing to express our deep concerns over the figures presented to the Thirlwall Inquiry with regards to extubation rates, particularly the claims about 1% and 40% accidental extubation rates. There appear to be three fundamental underlying issues:
• Making sense and understanding what the figures mean from a neonatal perspective
• What the figures were related to (the denominator in statistical terms)
• How the comparisons were made, and the reliability of that comparison
Questions about what figures relate to:
It is difficult for any health professional or statistician to understand what the headline figures mean. Richard Baker KC mentions “per shift”. Does this mean for each intubated baby per shift per nurse? For each intubated baby per shift (nurses often look after more than one ventilated baby)? Each intubated baby divided by the number of nurses on each shift? Each intubated baby divided by the number of nurses looking after ventilated babies? Each intubated baby looked after by Lucy Letby? The number of accidental extubations divided by the number of ventilated babies/shift?
Questions about data discrepancy:
Do the figures “make sense”? It is difficult to understand the claim that a Neonatal Unit has managed a 1% accidental extubation rate. Without a thorough and transparent explanation/publication, it is difficult to know how seriously (or not) to view these statements. We are concerned that this data has been influenced by improper methodology or inexperienced data analysis.
Questions about definition:
Sometimes endo-tracheal tubes can be completely removed because the clinician needs to exclude the possibility of dislodgement when there is a deterioration in a baby’s condition. Sometimes tubes can be removed because the clinician cannot be sure that the tube has been inserted correctly. Sometimes the definition can be stricter – and be defined in different terms, including some or all the following: inadequate/absent chest wall movement, desaturation without recovery, no clinical response to manual ventilation through the tube, changes in oxygen and carbon dioxide levels on blood measurement.
Questions about completeness of reporting data:
All clinicians also know that not all acute events (even if listed within a unit for mandatory ‘exception’ reporting as adverse events) get reported/recorded. We all know situations where one must rush off to other emergencies or reach the end of a tiring shift and although the event would be recorded in the individual patient record, the central recording of the event is not completed.
Questions about failure to detect abnormal trends through normal governance and adverse incident reporting:
Another key issue raised is the 40-fold increase in accidental extubations during certain shifts. If data quoted is subsequently shown to be robust, reliable and accurate, we question why such a drastic increase went unnoticed and unaddressed (for nearly a decade). The failure to raise this issue would in that case raise important questions and have profound implications for Liverpool Women’s Hospital (LWH).
Questions about scrutiny and supervision of those on training programmes:
Nurses undergoing intensive care training should always be supernumerary, and it would be normal practice for them to be supervised. If Lucy Letby was on a training programme at LWH, during this time, and the data is indeed shown to be reliable and representative, this would raise important questions for LWH about the level of supervision/support as well as the training she was being provided with during this period?
Questions about the methods used for statistical comparison:
It is not clear what statistical analysis of the samples took place. In addition, it is not possible to understand what statistical method was used for comparison between the two samples. The robustness and reliability of that comparison is also not clear (this is normally measurable in statistical terms). This brings into question the likelihood and limits of any variation that might arise due to random statistical variation (chance).
In summary, it is important that such presentations in public enquiries try to minimise avoidable distress to families. Of course, if the data is found to be robust, and therefore that further investigation is warranted, then it is essential that this is undertaken. However, the apparent careless presentation of unsubstantiated and uncorroborated figures is likely to create unnecessary distress and harm, and well as generating additional worry (for example, among parents of babies who were treated at LWH) should these figures be found not to have solid statistical and medical foundation. We hope that these issues will be taken seriously as the Thirlwall Inquiry proceeds.”