Indexing Standards and Usability Tests 
This paper provides reference information and complements the demonstration: 'Using Indexing Standards and Usability Tests' by Deborah Swain and Rebecca Oliver. Information covered in the paper includes historical background on indexing and on the ANSI Z39.4 standard for indexes. Questions about the effectiveness of standards are discussed. In addition, the paper describes one way to conduct a usability test on a back-of-the-book index: random analysis. (Three testing methods will be explained in the demonstration.)
Swain, Deborah E. STC Proceedings (1993). Articles>Editing>Indexing>Usability