They cannot use the medical evidence to determine whether an attempted murder took place. Attempted murder is all about intention. The medical evidence is there solely in those cases to show they suffered adverse events, not how close they did or didn't come to dying. All that needs to be shown is that something was done to the baby, with the intention of causing death.
In the example I gave above, with the empty gun, there would be no bullet fired, and no wounds. If I thought I was poisoning someone because I bought a bottle saying lethal poison, but there was a harmless substance inside it, and I added it to their drink, I've still committed attempted murder. In the same way you cannot look at these events and say the attempted murders weren't likely to cause death because, for instance, they didn't get the dose right or there were doctors on hand who would rescue them, or the babies who had insulin didn't go into a coma or collapse, the intention behind an act is an entirely different matter and totally unquantifiable by looking at what happened to the baby medically.
That is why I say intent for attempted murder can be assessed by the circumstances, and the circumstances include consideration of the deaths that happened. It would be improper for the jury to look at each case as a stand alone event. That is why they are being tried together.
JMO
Attempted Murder
In contrast to the offence of murder, attempted murder requires the existence of an intention to kill, not merely to cause grievous bodily harm:
R v Grimwood (1962) 3 All ER 285. The requisite intention to kill
can be inferred by the circumstances:
R v Walker and Hayles (1990) 90 Cr App R 226.
Homicide: Murder and Manslaughter | The Crown Prosecution Service
Part I
Attempts etc.
Attempt
1Attempting to commit an offence.
(1)If, with intent to commit an offence to which this section applies, a person does an act which is more than merely preparatory to the commission of the offence, he is guilty of attempting to commit the offence.
[
F1(1A)Subject to section 8 of the Computer Misuse Act 1990 (relevance of external law), if this subsection applies to an act, what the person doing it had in view shall be treated as an offence to which this section applies.
(1B)Subsection (1A) above applies to an act if—
(a)it is done in England and Wales; and
(b)it would fall within subsection (1) above as more than merely preparatory to the commission of an offence under section 3 of the Computer Misuse Act 1990 but for the fact that the offence, if completed, would not be an offence triable in England and Wales.]
(2)
A person may be guilty of attempting to commit an offence to which this section applies even though the facts are such that the commission of the offence is impossible.
(3)In any case where—
(a)apart from this subsection a person’s intention would not be regarded as having amounted to an intent to commit an offence; but
(b)if the facts of the case had been as he believed them to be, his intention would be so regarded,
then, for the purposes of subsection (1) above, he shall be regarded as having had an intent to commit that offence.
Criminal Attempts Act 1981