Sensible Medicine

John Mandrola · 19 Oct 2026

John Mandrola did not write this page.

Every claim below was made in this piece, quoted word for word and numbered in the order the piece makes them, so you can read it there rather than take our word for it. The sentence above each quote is our reading of the claim, not their wording. Each quote was checked against a stored copy of the page at build time; where the two differ, the quote is the fact.

Our reading
The NHS-Galleri trial did not show a reduction in late-stage cancers.

Their wordsYet there was no reduction in late-stage cancers, the primary endpoint.
Our reading
The Grail multicancer blood test has poor sensitivity and test characteristics.

Their wordsBut it had a terrible sensitivity of only 30%, meaning it missed a lot of cancers.
Our reading
The Grail test results are not reassuring because a positive test is often a false positive and a negative test does little to reduce baseline risk.

Their wordsA positive test leads to as many false positives as true positives, and a negative test is not at all reassuring.

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