Copyright (c) 2009 All rights reserved. http://works.bepress.com/erin_koffel Recent documents in Erin Koffel en-us Sun, 31 May 2009 05:51:01 PDT 3600 http://works.bepress.com/erin_koffel/2 http://works.bepress.com/erin_koffel/2 Mon, 06 Apr 2009 10:19:38 PDT We explicated the validity of the Inventory of Depression and Anxiety Symptoms (IDAS; Watson et al., 2007) in two samples (306 college students, and 605 psychiatric patients). The IDAS scales showed strong convergent validity in relation to parallel interview-based scores on the Clinician Rating version of the IDAS (IDAS-CR); the mean convergent correlations were .51 and .62 in the student and patient samples, respectively. With the exception of Well-Being, the scales also consistently demonstrated significant discriminant validity. Furthermore, the scales displayed substantial criterion validity in relation to DSM-IV mood and anxiety disorder diagnoses in the patient sample. We identified particularly clear and strong associations between (a) major depression and the IDAS General Depression, Dysphoria and Well-Being scales; (b) panic disorder and IDAS Panic; (c) posttraumatic stress disorder and IDAS Traumatic Intrusions; and (d) social phobia and IDAS Social Anxiety. Finally, in logistic regression analyses, the IDAS scales showed significant incremental validity in predicting several DSM-IV diagnoses when compared against the Beck Depression Inventory-II (Beck, Steer, & Brown, 1996) and Beck Anxiety Inventory (Beck & Steer, 1990). David Watson http://works.bepress.com/erin_koffel/1 http://works.bepress.com/erin_koffel/1 Mon, 06 Apr 2009 10:18:49 PDT Although sleep complaints are common in depression and anxiety, there is little agreement as to how they should be organized and assessed. It is also unclear whether sleep complaints show specificity with certain disorders or if they are nonspecific symptoms. We examined the structure of sleep complaints and the relations of these complaints to depression and anxiety in three samples: college students, older adults, and psychiatric patients. Exploratory and confirmatory factor analyses indicated that sleep complaints consistently defined two distinct dimensions: Insomnia and Lassitude. The Insomnia factor included indicators of early, middle, and late insomnia, as well as poor sleep quality. The Lassitude factor included measures of hypersomnia, fatigue, and sleepiness. Both factors were significantly related to symptoms and diagnoses of depression and anxiety. However, Lassitude was more strongly related to symptoms of depression and anxiety than was Insomnia. In addition, Lassitude showed specificity to measures and diagnoses of depression compared to anxiety disorders. This specificity can be explained by Lassitude's relation with negative and positive emotionality, both of which are components of depression. Erin Koffel