Panel Design

A panel design is used when researchers sample a group, or panel, of participants and then measure some variable or variables of interest at more than one point in time from this sample. Ordinarily, the same people who are measured at Time 1 are measured at Time 2, and soon. The successive measures are commonly referred to as waves. For example, a three-wave panel study would measure the same sample of participants on three separate occasions. The amount of time in between measurements is known as the interwave interval. The use of multiple measures on the same variable(s) over time allows for an assessment of longitudinal changes or stability on the variables of interest.

Perhaps the simplest and most common version of the panel design is ...