Measuring Personality Systems in Older Adults: Age-Neutrality of the Dutch BIS/BAS Questionnaire.

Introduction: With a rapidly aging population, age-neutrality of psychological instruments is becoming ever more important for accurate assessment of older adults. This study aims to test the age-neutrality of the Dutch Behavioral Inhibition System/Behavioral Approach System (BIS/BAS) scales by means of Differential Item Functioning (DIF) and Differential Test Functioning (DTF) analyses.

Methods: DIF and DTF analyses were conducted using an odds ratio approach.