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GeraClinic / Maternity Care Index / Methodology

How the Gera Maternity Care Index is calculated

The Gera Maternity Care Index is a reproducible 0–100 score derived entirely from the real Care Quality Commission (CQC) maternity ratings. This page sets out the exact weights, the formula, a worked example, the data provenance and the limitations — so anyone can reproduce or challenge the number.

What the index measures

The index answers one question: how good are NHS maternity services in England, as rated by the CQC? CQC uses a categorical scheme (Outstanding / Good / Requires improvement / Inadequate) with no numeric scale, so the index turns that distribution into a single 0–100 number, where 100 means every service is rated outstanding and lower means more services rated requires improvement or inadequate. It is computed identically for the overall rating and for each CQC key question, so the same number is comparable across cuts.

The formula

1. Rating weights

Each CQC rating band is given the same weight used for the Gera Provider Quality Score across GeraClinic: Outstanding 4, Good 3, Requires improvement 2, Inadequate 1. These evenly-spaced weights are the documented editorial choice; there is no other free parameter.

2. Weighted mean rating

meanWeight = (4·%O + 3·%G + 2·%RI + 1·%I) / total

The weighted mean sits between 1 (all inadequate) and 4 (all outstanding). Because it is share-based, it is identical whether the distribution is expressed as counts or the percentages CQC published.

3. Rescale onto 0–100 (GMCI)

GMCI = (meanWeight − 1) / 3 × 100 (rounded to 1 dp)

Subtracting 1 and dividing by 3 maps the 1–4 mean onto 0–100. Higher = better ratings. This is the only Gera-computed layer; every input is CQC’s real published figure.

Worked example — overall rating, England

  • CQC distribution (131 inspected services): 4% outstanding, 48% good, 36% requires improvement, 12% inadequate
  • weightedSum = 4×4 + 3×48 + 2×36 + 1×12 = 244
  • meanWeight = 244 / 100 = 2.44
  • GMCI = (2.44 − 1) / 3 × 100 = 48 / 100

Applying the same steps to CQC’s “Safe” key-question distribution (35% good, 47% requires improvement, 18% inadequate, none outstanding) gives the safety sub-index of 39 / 100.

Data provenance

The ratings come from CQC’s National Maternity Inspection Programme — an inspection of hospital maternity locations that had not been inspected since before March 2021 — reported in “National review of maternity services in England 2022 to 2024” (published September 2024). CQC published the overall and “Safe” rating distributions as percentages of the 131 inspected locations; those percentages are transcribed verbatim. The patient-experience figures come from the separate CQC 2024 Maternity Survey (120 NHS trusts, published 28 November 2024). No value is estimated or imputed.

Contains public sector information published by Care Quality Commission and licensed under the Open Government Licence v3.0. Source: CQC — National review of maternity services in England 2022 to 2024 (National Maternity Inspection Programme) (August 2022 – December 2023, published September 2024).

Contains public sector information published by Care Quality Commission and licensed under the Open Government Licence v3.0. Source: CQC — Maternity Survey 2024 (2024, published 28 November 2024).

Contains public sector information published by Gera Systems and licensed under the Open Government Licence v3.0 (source data). Source: Gera Maternity Care Index — derived from CQC maternity ratings (August 2022 to December 2023, published 3 July 2026).

Per-trust and per-region layer (in progress)

A hospital-level and NHS-region ratings breakdown is designed to load from the CQC “Care directory with ratings” open-data file, filtering the maternity service rows to the overall rating per location — the same monthly CQC extract already behind GeraClinic’s CQC ratings pages. Until each hospital-level number can be traced to that real file, no per-trust figure is shown: the national picture is the verified figure today. CQC did not publish a full national four-band split for these key questions in this release, so they are shown as framework rows only: Well-led, Effective, Caring, Responsive.

What the index does NOT show

  • It covers England only and is based on CQC ratings, not clinical outcomes such as mortality or morbidity.
  • The ratings come from a one-off national inspection programme (August 2022 to December 2023), not real-time monitoring; a service’s current rating may have changed on re-inspection.
  • It is a national/key-question summary — not (yet) hospital-level, and not a judgement about your own care.
  • Patient-experience survey figures are reported alongside the index but are not an input to it.
  • The index is information, not medical advice. For any concern about your pregnancy or birth, speak to your midwife, GP or maternity unit. GeraClinic is a private service and is not affiliated with the NHS or the CQC.

Update cadence

The National Maternity Inspection Programme distribution is fixed to that programme. Gera refreshes the index when CQC publishes new national maternity analysis, and the per-trust layer will follow the monthly CQC “Care directory with ratings” release. The figures here were last compiled on 3 July 2026.

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