Specialty hospitals - should they be included?

[robchallen]

trust_code name

1 RBS Alder Hey Children's NHS Foundation Trust
2 RBV The Christie NHS Foundation Trust
3 RGM Royal Papworth Hospital NHS Foundation Trust
4 RQ3 Birmingham Women's and Children's NHS Foundation Trust
5 RT3 Royal Brompton & Harefield NHS Foundation Trust

I notice a few hospitals in your mapping that are essentially specialist centres for specific conditions and would in theory take patients from all over the country. Some of them have a p_trust of 1 which I am surprised at as I'd have expected them to have a very broad geographical coverage - maybe a small numbers thing. I suspect the covid patients in these hospitals are incidental rather than admitted because of COVID, and I wonder if it would be better to exclude these 5 trusts before running the mapping.

[sophiemeakin]

Good point, thanks Rob.

Yes, I think you're right that the numbers are pretty small, especially given that the mapping is only based on admissions until the end of September 2020, plus the step where we exclude Trust-LTLA pairs with fewer than 10 will exacerbate this.

What is your concern with including these centres - that the mapping isn't very representative (which I agree on), or that including them will impact other Trusts' mappings?
For the former, I've been thinking about adding some measure of uncertainty for the mapping rather than just point estimates (although that will only flag that we don't know, rather than improving it!).
For the latter, I think it won't make a huge difference, since the % of admissions from a given UTLA to the Trusts (p_geo below for the Trust-LTLA mapping) seems to generally be <5%:

x trust_code trust_name geo_code geo_name p_trust p_geo
1 RBS Alder Hey Children's NHS Foundation Trust E08000012 Liverpool 1 0.0125
2 RBV The Christie NHS Foundation Trust E06000049 Cheshire East 0.294 0.0220
3 RBV The Christie NHS Foundation Trust E08000003 Manchester 0.196 0.0110
4 RBV The Christie NHS Foundation Trust E08000006 Salford 0.196 0.0224
5 RBV The Christie NHS Foundation Trust E08000007 Stockport 0.314 0.0277
6 RGM Royal Papworth Hospital NHS Foundation Trust E07000011 Huntingdonshire 1 0.108
7 RQ3 Birmingham Women's And Children's NHS Foundation Trust E08000025 Birmingham 1 0.0125
8 RT3 Royal Brompton & Harefield NHS Foundation Trust E09000005 Brent 0.304 0.0270
9 RT3 Royal Brompton & Harefield NHS Foundation Trust E09000009 Ealing 0.241 0.0303
10 RT3 Royal Brompton & Harefield NHS Foundation Trust E09000015 Harrow 0.241 0.0321
11 RT3 Royal Brompton & Harefield NHS Foundation Trust E09000017 Hillingdon 0.214 0.0420

What do you think?

[robchallen]

So I guess the worst one is that every patient in the Royal Papworth is from Huntingdonshire, and 10% of patients in Huntingdonshire end up at the Royal Papworth which doesn't feel representative.

Having said that I agree in most applications I should think it won't make a massive difference.