How it works
Trust the sources, then decide.
HealthDefence is designed so that you never have to take its word for anything. Here is how an answer is built, what checks it, and what has and has not been tested.
Grounding and citations
Answers are built from retrieved clinical text, not from a model's memory alone.
Before the council meets, passages are retrieved from a clinical reference corpus of about 54,000 passages: society guidelines, PubMed and PMC literature, ClinicalTrials.gov records, CDC pages and FDA drug labels. The corpus is refreshed weekly.
Each answer cites the passages it relied on, with title, source and link. A quotation is shown as a quotation only when it occurs word for word in the source; otherwise the source's opening is shown and marked. Citations to anything that was not retrieved are removed.
Medication safety reads each drug's current FDA label, and equivalent products come straight from the FDA Orange Book and the AEMPS register, each with its data date.
Faithfulness checks
Separate checks test whether the sources actually say what the answer claims.
- Entailment gate. A separate model (Claude Haiku) checks that each cited passage supports the statement it is attached to.
- Exact-quote checks. Every quoted FDA label sentence, and every quote in a lab finding, is matched by exact text against its source. Unconfirmed findings are shown apart and marked.
- Rules where rules suffice. Lab statuses (low, high, critical) are computed by fixed rules, and equivalent products involve no model at all.
- Missing inputs, stated. Each answer lists the case information that was not entered and anything it did not check, because the absence of a finding is not evidence of safety.
How it is tested today
Stated plainly, because it matters.
Internal testing, not a clinical validation study.HealthDefence is tested against small sets of cases written by its developers, with known answers. These tests catch regressions before a release and show the method. They are not evidence of clinical performance.
The council's answers in these tests are scored by a separate AI model acting as a reviewer, not by clinicians. The cases are few, mostly adult and outpatient; performance on rare conditions, children, and populations outside the US and Spain has not been measured.
A clinical validation study on real, de-identified records with clinician-adjudicated answers is being designed. It has not been run, and we will not quote accuracy figures until it has. Signed-in clinicians can read the current internal test results, with their limits, on the in-app About page.
The clinician stays in the loop
- Accounts are limited to clinicians whose licence has been verified (in the US, against the NPPES NPI registry).
- Every answer is information for you to review independently, with its basis shown.
- You can push back: re-run a consultation with your feedback and see how the answer changes.
- Nothing reaches a patient or a record unless you accept it, and generated documents are marked DRAFT for your review.
Not for emergencies
Do not use HealthDefence when a decision cannot wait for you to review its sources.Requests marked as emergencies are refused, troponin and CK-MB are not interpreted, and it does not detect or alert on deterioration, sepsis, stroke or myocardial infarction.
Regulatory position
In the United States, HealthDefence is designed to meet the four criteria for non-device clinical decision support in the FDA's guidance of 29 January 2026: it does not analyse images or signals; it works from medical information; it supports, rather than replaces, a professional's decision; and it shows the basis of its output so the professional can review it independently.
It has not been cleared or approved by the FDA, and this position has not yet been confirmed by regulatory counsel.
In the European Union it would likely be a medical device under the MDR. It is not CE-marked, and any EU use will be a pilot.
Join the clinician pilot
We are looking for licensed clinicians and practices to shape HealthDefence ahead of launch. Tell us about your practice and we will be in touch.