Factor structure and validity of the Inventory of Depression and Anxiety Symptoms-II (IDAS-II) in a chronic back pain treatment-seeking sample.

Many patients who seek treatment for chronic back pain are also at a higher risk of having comorbid anxiety- and depression-related disorders. Measures of mood and anxiety are routinely used in medical settings to screen for depression- and anxiety-related symptoms. However, factor analyses of other measures of mood and anxiety in medical settings often detect a somatization factor which, in turn, limits their discriminant validity for use across medical settings. The Inventory of Depression and Anxiety Symptoms-II (IDAS-II) is a comprehensive self-report inventory that assesses varying aspects of mood and anxiety. The purpose of this investigation is to examine the three-factor structure and validity of the IDAS-II in a chronic pain treatment-seeking sample. A total of 169 patients completed the IDAS-II and the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF) upon admission. Confirmatory factor analyses were computed using the scales of the IDAS-II and zero-order correlations between the IDAS-II factors from the best-fitting model and scale scores of the MMPI-2-RF. Overall, a three-factor structure of the IDAS-II was not supported; instead, a one-factor solution fit best. Using the MMPI-2-RF as external criteria, the one-factor of the IDAS-II correlated highest with the Somatic Complaints scale and the Demoralization scale. Overall, item content on the IDAS-II shares overlap with many symptoms that patients with chronic pain likely would endorse. Discussion about implications of using mood/anxiety measures and models in medical settings that are in line with the Hierarchical Taxonomy of Psychopathology (HiTOP) are discussed. (PsycInfo Database Record (c) 2022 APA, all rights reserved).