Longitudinal Structured Interview — Repeated Standardised Interviews Over Time

A longitudinal structured interview applies a fixed, standardised interview schedule to the same participants at two or more points in time. By holding the instrument constant across waves, the method enables genuine within-person change to be measured, trends to be tracked, and causal sequences to be examined with far greater confidence than a single cross-sectional interview can provide. It is widely used in panel studies, cohort research, and programme evaluations.