Learning and Evaluation/Archive/Learning modules/3Reliability & Validity

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Part 2: Reliability & Validity

Reliability and validity are terms frequently used to describe the accuracy in which proxy measures target a phenomena.

Reliability tells us how well a survey is able to give us the same information if we were to survey the same respondents over and over.

Validity is how well a survey is able to target the phenomena of interest.

Not reliable, not valid The survey is not measuring what it is aiming for and respondents are giving different answers each time the survey is administered.	----	-
Low reliability, low validity The survey questions are not close enough to the target and respondents are still giving different answers each time they respond to the survey.	----
Reliable, but not valid The questions are more reliable in that participants are answering similarly each time they are asked, however, the measurement is not yet targeting the phenomena.	----	..
Valid and reliable Questions are written so that respondents always respond the same way and the questions are giving the information needed.	----	.