the set of items measures several unrelated latent variables. The hierarchical "coefficient omega" may be a more appropriate index of the extent to which all of the items in a test measure the same latent variable. Several different measures of internal consistency are reviewed by Revelle & Zinbarg (2009). See also Cronbach's alpha Consistency (statistics) Reliability (statistics) References External links https://web.archive.org/web/20090805095348/http://wilderdom.com/personality/L3-2EssentialsGoodPsychologicalTest.html Comparison of assessments Statistical reliability