Making careful observations under various controlled conditions to test ideas

Whether a measure accurately measures what it intends to measure; measurement accuracy

Questions about how the world actually is that can be answered by systematically observing it

A process of systematically collecting and evaluating evidence to test ideas and answer empirical questions

A theoretical description of a construct (variable)

How a construct is measured in a study, providing concrete details like the measure used and scoring

Refers to the consistency of a measure across time points or between raters