Why is epact/PrescQIPP etc different?

[brianmackenna]

We frequently get questions (into the inbox and elsewhere) about why does x system have a different result to OpenPrescribing?

The answer is generally -
a) its a different datasource
b) its bsa data but they probably use different analytic code/inclusion criteria
We have many examples in sent inbox of this

I think we should add to the FAQ to handle this and minimise time responding

[speed-vm]

Response to query regarding difference between EPD and NHSBSA PCA data

In short, there is expected to be some disagreement between the two datasets based on where the prescription was issued and where it was dispensed.

OpenPrescribing uses the English Prescribing dataset which contains detailed information on prescriptions issued in England that have been dispensed in England, Wales, Scotland, Guernsey, Alderney, Jersey, and the Isle of Man. It does not include prescriptions that were issued in Wales, Scotland, Guernsey, Alderney, Jersey, and the Isle of Man.

Whereas, the NHS BSA PCA data provides details of the costs and volumes of all prescriptions dispensed in the community in England.

This is some more detail on these differences described in the NHS BSA PCA methodology, in section 7.5. Background Information and methodology (nhsbsa-opendata.s3.eu-west-2.amazonaws.com)

[speed-vm]

Doc for discussion here