# What London is prescribed

> Community prescribing by BNF chapter: items, quantity and the two published cost measures.

- Category: NHS
- Cadence: monthly
- Status: Published on a monthly cadence.
- Dataset key: `what-london-is-prescribed`
- Source: [NHS Business Services Authority](https://opendata.nhsbsa.net/dataset/english-prescribing-dataset-epd-with-snomed-code)
- Licence: Open Government Licence v3.0 — [terms](https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/)
- Canonical page: [https://londongraph.com/g/what-london-is-prescribed](https://londongraph.com/g/what-london-is-prescribed)
- Machine-readable record: [https://londongraph.com/data/what-london-is-prescribed](https://londongraph.com/data/what-london-is-prescribed)

## Methodology

Monthly English Prescribing Dataset aggregates for practices assigned to the NHS London region, joined to the matching official GP registered-patient snapshot. The chapter view counts prescription items dispensed in the community; it is not a count of patients and must never be interpreted as disease prevalence. Net ingredient cost is the basic list price measure, while actual cost reflects reimbursement adjustments. Practice-level combinations are used only inside ingestion and are not published.

## Visualisations

- [Prescription items](https://londongraph.com/g/what-london-is-prescribed): Compare dispensed prescription items across every BNF chapter.
- [Medicine quantity](https://londongraph.com/g/what-london-is-prescribed?view=quantity): Use treemap area to compare the source's published total quantity across chapters. Caveat: Quantity units vary between presentations and are not equivalent to prescription items or patients.
- [Actual cost](https://londongraph.com/g/what-london-is-prescribed?view=actual-cost): Compare the reimbursement-adjusted actual cost across BNF chapters.
- [Ingredient cost](https://londongraph.com/g/what-london-is-prescribed?view=ingredient-cost): Compare net ingredient cost, the basic list-price measure before reimbursement adjustments.

## Citation guidance

Attribute the original publisher named above and identify LondonGraph as the visualisation and methodology layer. Do not describe live values as a historical census, and do not present placeholder values as observations.