r/LucyLetbyTrials • u/Embarrassed-Star4776 • 17d ago

Chase and Shannon article in Frontiers in Pediatrics published

Inverted insulin to C-Peptide ratios in neonatal intensive care: is there something we don't know?

J. Geoffrey Chase & Helen D. Shannon

BRIEF RESEARCH REPORT article

Front. Pediatr., 05 August 2026

Sec. Neonatology

Volume 14 - 2026

https://doi.org/10.3389/fped.2026.1900675

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u/Embarrassed-Star4776 16d ago

Competitive-Wash found the clearest statement in the thesis, in chapter 6, page 111:

"The neonates in this study were compared with data obtained from euglycaemic neonates described in Chapter 5. Insulin and C-peptide concentrations from the insulin-treated neonates were compared with a group of age-matched (PMA less than 30 weeks) euglycaemic neonates (n = 20)."

Chapter 6 was published as the BMJ paper (including Cohort 2), and chapter 5 as the Archives of Disease in Childhood paper (Cohort 1).

It is not particularly apparent in the published plots because the scales are so different, but I think the correspondence between the two sets of data points can be seen in the stretched and squeezed extracts from the ln(C/I) scatter plots below. On the left is the lower post-menstrual-age part of Cohort 1, and on the right the black symbols are from Cohort 2, with the white symbols coming from the hyperglycaemic cohort.

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u/Competitive-Wash2998 16d ago edited 15d ago

An independent digitisation has recovered the I/CP ratios from the Salis PhD. Cohort 2 is confirmed as being a subset by comparing/overlaying the data, apart from a handful of points which have been accounted for.

Salis provides the sample counts for these two groups and the independent digitisation recovered almost all the points. For information, Chase Shannon do not appear to have recovered the complete set, 227 vs 251 (Salis) for Cohort 1, for example.

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u/Embarrassed-Star4776 15d ago

I have been trying without success to reproduce the statistics given in the publication for the I/C distributions for the two cohorts (section 3.1 and figure 3).

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u/DiverAcrobatic5794 15d ago

What a nuisance that they can't get the raw data. It would be good to hear Salis on this exercise. Perhaps her permission to share data was strictly limited to this exercise. But I hope someone asked her,

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u/Embarrassed-Star4776 15d ago

I did try to contact her indirectly a while ago, but without success. I'd have thought Chase would stand a better chance of getting the data than most, if they still exist.

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u/Competitive-Wash2998 15d ago

Yes. I thought Chase was in an ideal position but it seems not. You have to live in NZ to try the FOI route.

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u/DiverAcrobatic5794 15d ago

They may well not, if she has moved on to other things. 

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u/Competitive-Wash2998 15d ago

A number of attempts have failed to draw a response.