Statistics for the Scale Developer
Barbara C. Tilley · Oxford University Press eBooks · 2012
When a new scale is developed, as described in Chapter 1, the scale must undergo psychometric testing, including cognitive pretesting, assessments of the internal structure or clinimetrics including test-retest reliability, internal consistency, factor structure, differential item functioning, correlations with scores of the some construct from other instruments, and tests of the ability of the scale to detect change over time. If a scale is modified or administered in a new way, some psychometric testing of the revision is also required. There is a large body of statistical literature on each of the approaches to psychometric testing, and the presentation of extensive details is beyond the scope of this book. This chapter summarizes the major types of approaches and the focus of each approach, with some basic references to articles and software for those who wish to conduct these analyses.