Compass is still being developed and is effectively in beta. Some content and features may be incomplete, change, or not work as expected.

Content is anchored to trusted sources where available, but Compass has not yet been clinically reviewed. It provides general information rather than medical advice.

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Tests and measurements

Biomarker

Something measurable in the body that stands in for what is happening to a condition.

What it means

A blood level, a scan finding or a protein that reflects an underlying process. A useful one changes when the condition changes, which makes it a faster way to test whether a treatment is working than waiting to see how someone does.

Why you might hear it

  • It is central to why some trials can be shorter than others.
  • It is how neurofilament is usually described.

People who may help

Where Compass goes into this

About this explanation

These are plain explanations of words you may come across, not advice about your own situation. Where a word matters to a decision, the question pages go into it properly, and your own team is the place to take it.