Paper Prototyping Grows Up
http://www.stc.org/ConfProceed/2004/PDFs/0071.pdf

Snyder, Carolyn
STC Proceedings
2004

Abstract:

This paper summarizes findings from several research studies that examined the validity of paper prototyping in terms of uncovering usability problems. It also discusses the question of how paper prototypes might bias a usability test, and the role of case studies in the usability literature.