Reliability

Definition

The consistency of a measure or test over time or across different observers.

Example

 A questionnaire designed to measure self-esteem should yield similar results when administered to the same group of individuals on different occasions, assuming no real change in their self-esteem.

Why It Matters

Reliability matters because research needs to be consistent to be trusted. If a measure gives different results each time it's used, even when nothing has changed, it’s hard to know what to believe. Reliable tools help researchers collect dependable data, which makes the findings stronger and more useful.