Chapter 2. Principles of Measurement Scales
Published Online: 27 APR 2007
DOI: 10.1002/9780470024522.ch2
Copyright © 2007 John Wiley & Sons, Ltd
Book Title
Quality of Life: The Assessment, Analysis and Interpretation of Patient-Reported Outcomes, Second edition
Additional Information
How to Cite
Fayers, P. M. and Machin, D. (2007) Principles of Measurement Scales, in Quality of Life: The Assessment, Analysis and Interpretation of Patient-Reported Outcomes, Second edition, John Wiley & Sons, Ltd, Chichester, UK. doi: 10.1002/9780470024522.ch2
Publication History
- Published Online: 27 APR 2007
- Published Print: 2 MAR 2007
ISBN Information
Print ISBN: 9780470024508
Online ISBN: 9780470024522
- Summary
- Chapter
Keywords:
- measurement scale principles;
- QoL issues - constructs, latent traits or factors;
- QoL – multidimensional in nature;
- causal indicator and effect indicator in structural equation modelling;
- single-item versus multi-item scales;
- visual analogue scales (VAS);
- Cronbach's reliability coefficient for multi-item scales;
- traditional psychometrics based on summated scales;
- item response theory (IRT)
Summary
This chapter contains sections titled:
Introduction
Scales and items
Constructs and latent variables
Indicator variables and causal variables
Single global questions versus multi-item scales
Single-item versus multi-item scales
Psychometrics and item response theory
Psychometric versus clinimetric scales
Sufficient causes and necessary causes
Discriminative, evaluative and predictive instruments
Measuring quality of life: indicator or causal items?
Conclusions