GeraClinic / NHS Dentistry Access Index / Methodology
How the Gera NHS Dentistry Access Index is calculated
The Gera NHS Dentistry Access Index is a reproducible 0–100 score derived entirely from the real NHS Dental Statistics for England. This page sets out the exact formula, why there is no editorial constant, a worked example, how the 7 NHS regions are aggregated, the data provenance and the limitations — so anyone can reproduce or challenge the number.
What the index measures
The index answers one question: what share of adults still have recent NHS dental contact in an area? It takes one official NHS access metric — the share of adults seen by an NHS dentist in the previous 24 months, as a percentage of the adult population — and reports it on a single 0–100 scale, where 100 means universal access (every adult seen) and lower means a deeper dental desert. It is published nationally, for 7 NHS England regions and for 42 Integrated Care Boards, so the same number is comparable across every cut.
The formula
Adult access score (GNDAI)
Take the real adult 24-month access rate and report it on a 0–100 scale against universal access — 100 would mean every adult in the area was seen. NHS adult dental access has no single official percentage target (unlike a waiting-times standard), so universal access is the only benchmark that introduces no arbitrary constant anywhere: the score is exactly the published rate.
GNDAI = adult 24-month access rate (rounded to 1 dp)
Access gap = 100 − GNDAI (adults with no NHS dental contact)
Higher = better access. Because the score is the real rate, it can never be misread: an index of 30.6 means 30.6% of adults were seen, never “zero access”.
How regions are aggregated
NHS England groups its 42 Integrated Care Boards into 7 statutory regions. Each region’s score is not a simple average of its ICBs — it is population-weighted, so larger populations count proportionally:
region rate = Σ(adult population × access rate) ÷ Σ(adult population)
For June 2023, this ranks North East and Yorkshire highest (46.2 / 100, 46.2% of adults seen) and South East lowest (36 / 100, 36.0%). No value is estimated: the region figure is a transparent sum of the real per-ICB numbers.
Worked example — England, June 2023
- Adults seen by an NHS dentist in 24 months: 40.7% of the adult population
- GNDAI = 40.7 → 40.7 / 100
- Access gap = 100 − 40.7 = 59.3% of adults with no NHS dental contact
Why children are not in the score
NHS Dental Statistics also publishes a child 12-month access rate. Children are seen on a shorter recall and at a higher rate, so blending both populations into one number would require an editorial weight — exactly the kind of arbitrary constant this index avoids. The child rate is therefore reported alongside the index as context, never folded into the score.
Data provenance
Every figure the index consumes is taken directly from NHS Dental Statistics for England, Table 3e (geographical breakdown), which reports adult and child access as a percentage of population by Integrated Care Board. No value is estimated or imputed. The index — reporting the real access rate on a 0–100 universal-access scale and population-weighting it to regions — is the only Gera-computed layer, and it is fully specified above.
Contains public sector information published by NHS Digital / NHS England and licensed under the Open Government Licence v3.0. Source: NHS Dental Statistics for England 2022-23 — Table 3e (Geographical Breakdown) (June 2023, published 24 August 2023).
Contains public sector information published by Gera Systems and licensed under the Open Government Licence v3.0 (source data). Source: Gera NHS Dentistry Access Index — derived from NHS Dental Statistics for England open data (June 2023, published 3 July 2026).
What the index does NOT show
- It covers England only, and only the adult 24-month NHS access measure — not private dental access, and not waits within other UK nations.
- It is national, regional and ICB-level — not practice-level, and not whether a specific dentist is taking new NHS patients today.
- “Seen” means any NHS course of treatment in the window; it does not measure how easy it was to get that appointment, how long the wait was, or whether the person wanted an NHS place and could not get one.
- The reference period is June 2023. Access can change between releases; always check the reference period before quoting a figure.
- The index is a summary measure and is not dental advice. For a dental problem, contact an NHS dentist or NHS 111; in an emergency call 999.
Update cadence
NHS England (via the NHS Business Services Authority and NHS Digital) publishes NHS dental access statistics on a regular schedule. Gera recomputes the index on each release. The figures here are for June 2023 and were last recomputed on 3 July 2026.
Licence: Open Government Licence v3.0. Contains public sector information published by NHS England.