The Anxiety Depression Distress Inventory–27 (ADDI–27): New Evidence of Factor Structure, Item-Level Measurement Invariance, and Validity

Abstract

ABSTRACTThree studies examining the factor structure and psychometric properties of the Anxiety Depression Distress Inventory–27 (ADDI–27) extended the initial instrument development studies for this recently introduced inventory. The ADDI–27 is an empirically derived short form of the Mood and Anxiety Questionaire–90 (MASQ–90) comprising three scales: Positive Affect, Somatic Anxiety, and General Distress. The main objectives of Study 1 (N = 700) were to examine the factor structure of the ADDI–27 and its measurement invariance across gender at the item level. The objective of Study 2 (N = 538) was to examine evidence for the convergent and discriminant validity of scores on the ADDI–27. The objective of Study 3 (N = 240) was to assess further evidence for the nomological network and convergent and discriminant validity of the ADDI–27 scores. Results of exploratory structural equation modeling yielded strong support for a 3-factor model, with approximate fit indexes meeting or exceeding the conventional cutoffs. With p ≤ .001 as the criterion for detecting noninvariance, results of measurement invariance analysis suggested that all of the ADDI–27 items were invariant across gender. Results of multivariate validity analyses across 2 studies provided support for the convergent and discriminant validity of scores on the ADDI–27 scales.