I don't think that people understand how unlikely it is that this number of infants would die within that timeframe, even in the context of grossly substandard care. The claims that they were "very premature" and "very seriously ill" are false and are a demonstration of posters ignorance on this subject. For example, a baby that is a little tricky to wean from CPAP is a completely routine situation in a NICU. Babies in this kind of condition cannot be expected to die, over and over again. Not even if they were receiving substandard care unless they were all dying eg of the same infectious agent which they very clearly were not.
Substandard care, as in the example cited up thread, still involves a sequence of events that can explain the deterioration / death. Eg a misplaced ET tube. Not just spontaneous unexplained deterioration, always in the presence of one member of staff.
For this to happen once or even a few times could be very unfortunate. But it happened over and over forming a consistent pattern of unexplained deaths far and away exceeding the worse mortality rates in the country, let alone tbe unit. These deaths always occured in presence of LL and frequently on milestone occasions.
If they were receiving grossly substandard care, how was it that many of the babies had improved, were doing well, and were approaching discharge at the point at which they unexpectedly collapsed, for no apparent reason, and always in the presence of LL. Why is that deaths resulting from substandard care, only happened when LL was present and care returned to a normal standard as soon as she was not working on the unit?
Regardless this case was not just made on statistics "what are the chances of that number of babies dying under her care". The prosecution assembled multiple independent expert witnesses with appropriate medical training, all of whom independently reached very similar conclusions for several infants - their conclusion was that these infants had been intentionally harmed. The conclusions of a postmortem are not unchangeable and the pathologists conclusions are always informed by the context they are given. It's not that surprising that examined individually, the pathologist would not have considered "murder" as a possible context for the deaths.
Lucy's presence at the time of the deteriorations, which were concluded by multiple experts independently to be the result of intentional injury, was then corroborated by documentary and witness evidence. Her attempts to conceal her presence by falsifying notes is a further piece of evidence. Her inability to recall events in her defence is a further piece of evidence.
Note that Lucy was not charged with all of the deaths that took place on the unit. The experts did not think "ah there was a murderer on the loose so all of these babies were definitely injured" nor was she charged for every event at which a baby deteriorated solely under her care, a "what are the odds" blanket approach.