Internal Consistency, Retest Reliability, and Their Implications for Personality Scale Validity

The authors examined data (N = 34,108) on the differential reliability and validity of facet scales from the NEO Inventories. They evaluated the extent to which (a) psychometric properties of facet scales are generalizable across ages, cultures, and methods of measurement, and, (b) validity criteria are associated with different forms of reliability. Composite estimates of facet scale stability, heritability, and cross-observer validity were broadly generalizable. Two estimates of retest reliability were independent predictors of the three validity criteria; none of three estimates of internal consistency was. Available evidence suggests the same pattern of results for other personality inventories. Internal…