About this library
How we check facts
Every claim in this library traces to a public source the editors opened and read. This page explains how sources are chosen, how uncertainty is shown and how mistakes are fixed.
Which sources count
Answers draw on national health services, government research institutes, patient-information pages from major hospitals, clinical guidelines and peer-reviewed reviews. Commercial pages, personal blogs and anything that sells treatment are not used as evidence. Each answer lists its sources at the end with what each was used for.
How claims are checked
A number, date or named guideline goes in only if it appears on a source page that was opened and read for that purpose. If two sources disagree, the answer says so instead of choosing one quietly. If a claim cannot be supported, it is dropped, which is why some pages are short.
How uncertainty is shown
Where evidence is limited or disputed, the page says that in plain words. Advice is attributed to the body that gave it, such as a national health service, and is not stated as the library's own instruction. Nothing here tells a reader to start or stop a treatment.
What the pages never do
They do not diagnose, interpret scans for individuals, or recommend an operation, a medicine or a provider. Each page names situations in which the sources say to see a clinician.
Dates and corrections
Each page shows the date it was last checked. Sources are re-read when pages are revised. If you spot an error or know a better source, write to the editors through the contact page and the page will be reviewed. Material corrections are made on the page itself. Read what the library is for in the about page.