Ask for numbers that make the size of a result easier to interpret.
Understand the question
A percentage can be expressed relative to a starting value or as an absolute difference. Ask which measure a headline uses and what the baseline was. Without that context, a large-looking percentage can be difficult to interpret responsibly.
Put it in everyday context
If a claim announces a major reduction, ask what happened in each comparison group and over what time. An example number in an advertisement should not be assumed to represent your personal chance of benefit. Keep the outcome and timeframe visible.
A comparison to avoid
A dramatic relative number without baseline information can make a small change look much larger than it is.
Your practical checklist
- Find the baseline
- Ask for both comparison values
- Check the timeframe
- Review uncertainty
Bring a focused question
What is the absolute difference behind the percentage being advertised?
Save this question with your notes so the next conversation starts with the issue you want to understand.
Sources & further reading
Sources checked 2026-10-05. Links provide background on the topic; practical checklists are editorial planning suggestions. This guide has not received independent clinical review. Read our standards and disclosure.
