, Volume 53, Issue 1, pp 63–70

Internal consistency of tests: Analyses old and new

  • Lee J. Cronbach

DOI: 10.1007/BF02294194

Cite this article as:
Cronbach, L.J. Psychometrika (1988) 53: 63. doi:10.1007/BF02294194


A coefficient derived from communalities of test parts has been proposed as greatest lower bound to Guttman's “immediate retest reliability.” The communalities have at times been calculated from covariances between itemsets, which tends to underestimate appreciably. When items are experimentally independent, a consistent estimate of the greatest defensible internal-consistency coefficient is obtained by factoring item covariances. In samples of modest size, this analysis capitalizes on chance; an estimate subject to less upward bias is suggested. For estimating alternate-forms reliability, communality-based coefficients are less appropriate than stratified alpha.

Key words

communality internal-consistency reliability 

Copyright information

© The Psychometric Society 1987

Authors and Affiliations

  • Lee J. Cronbach
    • 1
  1. 1.Center for the Study of Youth DevelopmentStanford University