Document Type


Peer Reviewed


Publication Date


NLM Title Abbreviation

Psychol Assess

Journal/Book/Conference Title

Psychological Assessment

PubMed ID


DOI of Published Version



We describe a new self-report instrument, the Inventory of Depression and Anxiety Symptoms (IDAS), which was designed to assess specific symptom dimensions related to major depression and related anxiety disorders. We created the IDAS by conducting principal factor analyses in three large samples (college students, psychiatric patients, community adults); we also examined the robustness of its psychometric properties in five additional samples (high school students, college students, young adults, postpartum women, psychiatric patients) that were not involved in the scale development process. The IDAS contains 10 specific symptom scales: Suicidality, Lassitude, Insomnia, Appetite Loss, Appetite Gain, Ill Temper, Well-Being, Panic, Social Anxiety, and Traumatic Intrusions. It also includes two broader scales: General Depression (which contains items overlapping with several other IDAS scales) and Dysphoria (which does not). The scales (a) are internally consistent, (b) capture the target dimensions well, and (c) define a single underlying factor. They show strong short-term stability, and display excellent convergent validity and good discriminant validity in relation to other self-report and interview-based measures of depression and anxiety.


major depression, anxiety disorders, scale development, factor analysis


This research was supported by National Institute of Mental Health Grant R01-MH068472 to David Watson and by a grant from the University of Minnesota Press to Roman Kotov.

Published Article/Book Citation

The definitive version was published in Psychological Assessment, 19:3 (2007) pp. 253-268. DOI: 10.1037/1040-3590.19.3.253


Author Posting. Copyright © American Psychological Association, 2007. This article may not exactly replicate the final version published in the APA journal. It is not the copy of record. It is posted here by permission of the APA for personal use, not for redistribution.