Some medical words and phrases explained


This means that people who believe themselves to be well have tests to find out if they are at risk of particular conditions. If someone has a symptom, screening tests are not applicable - they are only for people with no symptoms.

Secondary prevention

To try and stop something from happening again, for example, if someone has had a stroke, secondary prevention aims to stop another stroke from happening.


Another term for placebo, but often used to describe ‘sham surgery’ when patients either have a ‘real’ operation or a procedure that feels and looks like a real operation but isn’t.


When people feel something is wrong, for example, a fever, a cough, and muscle aches can be symptoms of the flu, or a breast lump might be a symptom of cancer. Symptoms are felt by the person having them.

Systematic reviews

A way of searching through all the research on a subject, looking carefully for research that hasn’t been published in medical journals or isn’t obvious. This is usually a good way of making sure that all the research is weighed up before judging whether treatments work or not.