Every dimension, weight, formula, and adjustment behind a GHC ranking is public. The same data produces the same score on every run.
Every doctor's composite score is the weighted aggregation of four dimensions. Each dimension is computed from a publicly-named data source and carries its own confidence interval before contributing to the final number.
AHRQ Patient Safety Indicator 90 · v2025
Composite of avoidable complications across surgeries and inpatient admissions. Case Mix Index multipliers ensure a doctor who accepts heavier cases is not penalised.
Booking-fee ledger + per-procedure settlement records
Cost-effectiveness versus outcomes versus regional benchmarks. The booking fee and any per-procedure settlement are weighed against the recorded outcomes for comparable cases.
SF-36 + EQ-5D + VAS questionnaires, collected post-procedure and at follow-up
Function, pain, and daily-life recovery as reported by patients themselves. Responses are weighted by case mix so heavier cases count for more, and a neutral prior holds until enough responses have been collected.
Regulator co-signs, audit-freshness, professional lineage within the peer cohort
Region-aware governance signals. A doctor backed by recent regulator endorsements and a verified academic chain accumulates standing here.
The baseline weights (40/30/20/10) apply when a specialty cohort has fewer than 30 doctors with comparable data. Once a cohort reaches 30 or more, the weights are recomputed from the data itself using the Entropy Weight Method. Dimensions with the most variation across the cohort earn proportionally more weight — this prevents any single dominant signal from masking the others when the data is rich.
A multiplier applied to D1 so that a doctor who accepts heavier cases is not penalised. The CMI table is updated annually and published alongside this page.
The four cleaned, weighted dimensions are combined using TOPSIS — Technique for Order of Preference by Similarity to Ideal Solution. The resulting score is clipped to a 0 to 100 scale. Same inputs, same output, every time.
Ranking scores are written exclusively by a separate compute service that has no administrative write path. The formula hash above can be compared against any historical hash in the changelog below — if the hashes match, the algorithm has not changed; if they differ, the changelog explains why.
The algorithm runs weekly on every active cohort. A doctor's rank moves when new patient-reported responses arrive, when the peer cohort changes size, or when the algorithm version itself is updated. All three causes are logged in the doctor's own Provenance section on their public profile.
Only the initial build is published today. Each new version will be appended here with its formula hash and a summary of changes, so any score on the platform stays verifiable against the version it claims.
First build of the GHC ranking algorithm. Baseline weights 40 / 30 / 20 / 10 across the four dimensions. The Entropy Weight Method activates once a cohort reaches 30 doctors. TOPSIS aggregation and the CMI adjustment are published on this page and open to independent review.
Advertising never buys ranking position. Sponsored placements, where they exist, are clearly labelled and never appear inside ranked lists. The compute service runs as a separate system from any commercial product surface, and patient-paid features have no read access to the scoring inputs.
A quarterly external audit confirms that the published formula matches the running formula. Audit reports are linked on /trust.
→ /trust
