When the consistency of collected data is measured at different points of time, it is identified as

Measuring the consistency of the same instrument on the same people at two different times is test-retest reliability.

A high correlation between the two administrations shows the measure is stable over time.

Inter-rater reliability instead checks agreement between different observers scoring the same behaviour.

Split-half reliability correlates two halves of a single test taken once, gauging internal consistency.

Internal reliability concerns whether items within a scale hang together, not stability across time.

A long gap between the two tests can lower the coefficient through real change or memory effects.