4. Multi-Item Scales

  1. Peter M. Fayers1,2 and
  2. David Machin3,4

Published Online: 8 MAR 2002

DOI: 10.1002/0470846283.ch4

Quality of Life: Assessment, Analysis and Interpretation

Quality of Life: Assessment, Analysis and Interpretation

How to Cite

Fayers, P. M. and Machin, D. (2000) Multi-Item Scales, in Quality of Life: Assessment, Analysis and Interpretation, John Wiley & Sons, Ltd, Chichester, UK. doi: 10.1002/0470846283.ch4

Author Information

  1. 1

    Medical Research Council Clinical Trials Unit, London, UK

  2. 2

    Unit of Applied Clinical Research, Norwegian University of Science and Technology, Trondheim, Norway

  3. 3

    NMRC Clinical Trials & Epidemiology Research Unit, Singapore

  4. 4

    School of Health and Related Research, University of Sheffield, UK

Publication History

  1. Published Online: 8 MAR 2002
  2. Published Print: 18 APR 2000

ISBN Information

Print ISBN: 9780471968610

Online ISBN: 9780470846285



  • significance tests;
  • correlations;
  • construct variability;
  • Cronbach's α;
  • internal consistency;
  • factor analysis;
  • multitrait-scaling analysis;
  • multitrait-multimethod analysis;
  • convergent and discriminant validity


Methods that are specific to multi-item scales are considered. Ways of exploring relationships amongst the constituent items of a multi-item scale are examined and also between the individual items and the scale to which they are hypothesised as belonging. Most of these methods rely upon examination of correlations. Do the items in a multi-item scale correlate strongly with each other? Do they correlate weakly with items from other scales? Do items correlate with the score of their own scale? Cronbach's α, multitrait-scaling analysis, and factor analysis are three of the most frequently used methods for exploring these correlations.