Further evidence for score reliability and validity of the Anxiety Depression Distress Inventory-27 scale

Abstract

ABSTRACT We conducted several analyses with data from undergraduate students (N = 309) and active duty US Air Force Security Forces personnel (N = 273) to examine the utility of scores on the Anxiety Depression Distress Inventory-27 (ADDI-27). The three specific dimensions of the ADDI-27 include Positive Affect, Somatic Anxiety, and General Distress, each composed of nine relevant and representative items. Internal consistency reliability estimates for scores on the scales were strong across the study groups (coefficient-α values ≥ .80). Results of analyses using differential item functioning showed that the groups interpreted the contents of the ADDI-27 items similarly. At the scale-level analyses, the undergraduate student sample reported higher somatic and general distress symptoms compared to the Air Force sample. Evidence for concurrent validity was adequate. Examples of the concurrent measures were the meaning in life, mental health functioning, and sources of social support self-report instruments. Taken together, results support the use of the ADDI-27 for assessing clusters of somatic anxiety, depression, and general distress in the current study samples.