What is the difference between reliability and validity?

Reliability refers to how consistent the results of a study are or the consistent results of a measuring test.

This can be split into internal and external reliability. Internal reliability refers to how consistent the measure is within itself. A personality test should produce the same results every time for the same participant. 

External reliability refers to how consistent the results are when the same procedures are carried out for a test. For example, if a research study takes place, the results should be almost replicated if the study is replicated. 

Validity refers to whether the study or measuring test is measuring what is claims to measure. Internal validity refers to whether it is exclusively the independent variable causing the change or whether there are confounding variables. External validty refers to how well the laboratory study can be generalised to real life settings. 

Remember, something can have reliability but not validity and validity but not reliability. 

Answered by Natalie H. Psychology tutor


See similar Psychology A Level tutors
Illustration of a video tutorial

Need help with Psychology?

One to one online tuition can be a great way to brush up on your Psychology knowledge.

Have a Free Meeting with one of our hand picked tutors from the UK’s top universities

Find a tutor

Related Psychology A Level answers

All answers ▸

What is an advantage and disadvantage of oppertunity sampling?

To what extent can the behaviourist approach in psychology be understood to be supportive of the nurture argument

Explain an example of classical conditioning.

What is the difference between quantitative data and qualitative data?

We're here to help

+44 (0) 203 773 6020support@mytutor.co.ukContact us
Facebook logoTwitter logoGooglePlus logoLinkedIn logo

© MyTutorWeb Ltd 2013–2021

Terms & Conditions|Privacy Policy