Fiducia TogetherReliability and validity
Whether a result repeats, and whether it measures what it claims to.
Please note: This page explains a word or a process in education. It is general information about the system, the law and the guidance in England — not advice about your child, your school or your exam. If a decision is going against you, get advice from one of the free services we link to before you agree to anything or miss a deadline. If you are revising, check your own exam board's specification: boards word things differently and yours is the one that marks you.
What it is
Reliability is consistency: the same method gives the same result. Validity is accuracy of concept: the method actually measures what it says it does.
Where it applies
Science, psychology, sociology and geography.
How it works
They are independent. A broken but consistent instrument is reliable and invalid. A well-designed one-off measurement may be valid and unreliable.
In social research, quantitative methods tend to be more reliable and qualitative more valid, which is the basis of the methodological argument.
How to use it in your work
Use the words precisely — they are not interchangeable and questions test exactly that.
When evaluating a study, address both, and say how each could be improved.
Where to get help
Your teacher and your board's specification and mark scheme.
Where to read more
Last reviewed 2026-08-28 by Fiducia Together · Next review due 2027-08-28
Please note: This page explains a word or a process in education. It is general information about the system, the law and the guidance in England — not advice about your child, your school or your exam. If a decision is going against you, get advice from one of the free services we link to before you agree to anything or miss a deadline. If you are revising, check your own exam board's specification: boards word things differently and yours is the one that marks you.