A twenty per cent lower risk of what, exactly?

Reports on health, healthcare and adult education — and a calculator that turns the percentage in a health headline back into the number of people it describes. These are summaries of what was published. Nothing here is advice about your own health.

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Is urgent care cheaper than the ER?

Sudden severe symptoms appear Yes, urgent care is usually cheaper than the emergency room, but the more useful question to ask first is whether the symptom is life-threatening at all — cost only matters…

Health & medicine

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Healthcare & policy

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Adult education

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What the percentage means

Health headlines report the relative change and almost never the absolute one. Put in the baseline risk and the percentage a study reported, and this returns the two numbers that actually describe it: how many people in a thousand, and how many would have to be treated for one of them to benefit.

Open the risk calculator →
  • Relative change turned into people per thousand
  • The absolute difference, in percentage points
  • Number needed to treat, or to harm
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Corrections

Has a result here been superseded?

Health reporting ages badly and dangerously: guidance changes, a trial fails to replicate, a drug is withdrawn. If you know that has happened to something on this site, tell us and we will note it on the article.

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