Validity and psychometric equivalence of the German version of the Big Five Inventory in young, middle-aged and old adults

In a study with 480 young, middle-aged, and old adults the psychometric equivalence and external validity of the German version of the Big Five Inventory (BFI) was examined across age groups. In addition, external validity of the BFI was explored in relation to general intelligence, positive affect, negative affect, social satisfaction, control beliefs, and social network size. Findings suggest a five factor solution of personality constructs that is found to be invariant across the three age cohort groups. Moreover, there is good indication of external validity of the five factors that is found to be equivalent across the three age groups. In a follow-up study with 45 older adults, the BFI was assessed twice within a time interval of 5 months. Moderate to high retest stability was observed. Findings suggest that the BFI is well-suited for measuring the five factor model of personality and is particularly adequate for application in diverse and age heterogenous samples.