Saturation

Saturation is broadly defined as the stage in qualitative research where no new, relevant information emerges from additional interviews. Saturation has become the conceptual yardstick by which sample sizes for qualitative inquiry are judged. The concept of saturation was first introduced into the field of qualitative research as theoretical saturation by Barney Glaser and Anselm Strauss in their 1967 book The Discovery of Grounded Theory. They defined the term as the point at which “no additional data are being found whereby the [researcher] can develop properties of the category” (p. 61). Their definition was specifically intended for the practice of building and testing theoretical models using qualitative data and refers to the point at which a theoretical model being developed stabilizes.

As the use of qualitative ...