Department of Psychology Publications

Iowa Sleep Disturbances Inventory (ISDI) (Expanded)

Erin Koffel — Thu, 22 Dec 2011 10:59:35 PST

The Iowa Sleep Disturbances Inventory (ISDI) can be used to measure a wide range of sleep disturbances. This expanded version includes two additional scales (Sleep Paralysis, Sleep Hallucinations). Please contact the author for validation information.

Further Validation of the Iowa Sleep Disturbances Inventory

Erin Koffel — Mon, 18 Jul 2011 13:59:42 PDT

This study examined the reliability and validity of an expanded version of the Iowa Sleep Disturbances Inventory (ISDI; Koffel & Watson, 2010) in 2 samples (219 college students and 200 psychiatric patients). The expanded ISDI includes the scales of Sleep Paralysis and Sleep Hallucinations. These scales, along with the Nightmares scale, help define a higher order factor entitled Unusual Sleep Experiences. This factor was distinct from the factors of Insomnia and Lassitude that were reported previously. The expanded ISDI showed strong evidence of convergent and discriminant validity with the corresponding interview ratings on a clinician rating version of the ISDI. Mean convergent correlations were .68 in students and .70 in patients. Convergent correlations were significantly higher than discriminant correlations in 99.8% of the 624 comparisons. This study also reports the associations of higher order sleep factors with questionnaire and interview measures of pathological symptoms (e.g., depression, anxiety, dissociation, and schizotypy). The Lassitude factor was specific to dysphoria, whereas the Unusual Sleep Experiences factor was specific to posttraumatic stress disorder (PTSD) and dissociation. Finally, several ISDI scales showed strong evidence of specificity in relation to pathological symptoms; in particular, there were strong associations between (a) ISDI Fatigue and measures of dysphoria, (b) ISDI Nightmares and measures of PTSD, and (c) ISDI Sleep Hallucinations and measures of dissociation.

Japanese PANAS

David Watson et al. — Thu, 17 Feb 2011 14:44:58 PST

The PANAS-X: Manual for the Positive and Negative Affect Schedule - Expanded Form

David Watson et al. — Wed, 16 Feb 2011 13:05:31 PST

Iowa Sleep Disturbances Inventory (ISDI)

Erin Koffel — Wed, 12 May 2010 07:07:33 PDT

The Iowa Sleep Disturbances Inventory (ISDI) can be used to measure a wide range of sleep disturbances. Please contact the author for validation information.

Unusual sleep experiences, dissociation, and schizotypy: Evidence for a common domain.

Erin Koffel et al. — Wed, 10 Feb 2010 07:45:01 PST

This paper reviews studies that have examined associations between unusual sleep experiences (including nightmares, vivid dreaming, narcolepsy symptoms, and complex nighttime behaviors) and dissociation and schizotypy. Using correlational studies and structural analyses, evidence is provided that unusual sleep experiences, dissociation, and schizotypy belong to a common domain. It is demonstrated that unusual sleep experiences show specificity to dissociation and schizotypy compared to other daytime symptoms (e.g., anxiety, depression, substance use) and other sleep disturbances (e.g., insomnia, lassitude/fatigue). The paper also outlines the methodological limitations of the existing evidence and makes suggestions for future research. Finally, three models for the overlap of daytime and nighttime symptoms are reviewed, including biological abnormalities, trauma, and personality traits. Although further research is needed, it is suggested that daytime and nighttime symptoms result from problems with sleep-wake state boundaries, which may be precipitated by stress or trauma. In addition, association between daytime and nighttime symptoms can be attributed to the higher order personality trait of Oddity.

Personality Development in Emerging Adulthood: Integrating Evidence from Self- and Spouse-Ratings

David Watson et al. — Fri, 27 Mar 2009 13:03:48 PDT

We examined self- and spouse-ratings in a young adult newlywed sample across a 2-year interval. Rank-order stability correlations were consistently high and did not differ across the two types of ratings. As expected, self-ratings showed significant increases in conscientiousness and agreeableness—and declines in neuroticism/negative affectivity—over time. Spouse-ratings yielded a very different pattern, however, showing significant decreases in conscientiousness, agreeableness, extraversion and openness across the study interval. Spouse-ratings also showed evidence of a “honeymoon effect”, such that they tended to be more positive than self-ratings at Time 1. This effect had dissipated by the second assessment; in fact, the spouse-ratings now tended to be more negative at Time 2. Analyses of individual-level change revealed little convergence between self- and spouse-rated change, using both raw change scores and reliable change index (RCI) scores. Finally, correlational and regression analyses indicated that changes in spouse-ratings were significantly associated with changes in marital satisfaction; in contrast, changes in self-ratings essentially were unrelated to marital satisfaction. These results highlight the value of collecting multimethod data in studies of adult personality development.

The Two-Factor Structure of Sleep Complaints and Its Relation to Depression and Anxiety

Erin Koffel et al. — Thu, 26 Mar 2009 11:40:35 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.

Patient Preference for and Reports of Provider Behavior: Impact of Symmetry on Patient Outcomes

Jamie A. Cvengros et al. — Thu, 26 Mar 2009 09:45:25 PDT

Objective: Research has suggested that congruence between patient characteristics and contextual characteristics is a more robust predictor of outcomes than either patient or context characteristics alone. The goal of the present study was to examine the degree of congruence between patient preferences for the clinical encounter and reports of analogous dimensions of provider behavior and the effects of this congruence on patient outcomes. Design: 218 patients with diabetes (predominately type 2) completed measures of preference for and ratings of perceived provider behavior in three domains (1) information sharing, (2) behavioral involvement, and (3) socioemotional support. Main Outcome Measures: Patient satisfaction, self-reported adherence, and a clinical marker of diabetic control (hemoglobin A1c) were the outcomes of interest. Results: Congruence in information sharing and congruence in behavioral involvement were predictive of glycemic control and self-reported adherence, respectively. Congruence in behavioral involvement and congruence in socioemotional support were predictive of greater patient satisfaction. Conclusion: These findings provide further support for the importance of congruence between patient characteristics and contextual characteristics in predicting patient outcomes.

Further validation of the IDAS: Evidence of Convergent, Discriminant, Criterion, and Incremental Validity

David Watson et al. — Thu, 26 Mar 2009 09:45:24 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).

Investigating the Construct Validity of the Dissociative Taxon: Stability Analyses of Normal and Pathological Dissociation

David Watson — Thu, 26 Mar 2009 09:45:24 PDT

Previous research has suggested the existence of a pathological dissociative taxon. However, relatively little is known about this taxon. This study examined the two-month retest stability of this taxon—together with other measures of dissociation and the Big Five—in a sample of 465 undergraduates. Contrary to expectation, taxon scores were only modestly stable and were substantially less stable than the other measures, including continuous indicators of dissociation. Furthermore, most individuals who were identified as taxon members at one assessment were classified as non-members at the other. These results challenge the existence of a pathological dissociative taxon. More generally, these data demonstrate that statistically-identified taxa need to be explicated through the normal process of construct validation.

Rethinking the mood and anxiety disorders: a quantitative hierarchical model for DSM-V.

David Watson — Thu, 26 Mar 2009 09:45:23 PDT

The fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 1994) groups disorders into diagnostic classes on the basis of the subjective criterion of "shared phenomenological features." There are now sufficient data to eliminate this rational system and replace it with an empirically based structure that reflects the actual similarities among disorders. The existing structural evidence establishes that the mood and anxiety disorders should be collapsed together into an overarching class of emotional disorders, which can be decomposed into 3 subclasses: the bipolar disorders (bipolar I, bipolar II, cyclothymia), the distress disorders (major depression, dysthymic disorder, generalized anxiety disorder, posttraumatic stress disorder), and the fear disorders (panic disorder, agoraphobia, social phobia, specific phobia). The optimal placement of other syndromes (e.g., obsessive-compulsive disorder) needs to be clarified in future research.

Development and Validation of the Inventory of Depression and Anxiety Symptoms (IDAS)

David Watson et al. — Thu, 26 Mar 2009 09:45:22 PDT

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.

Dissociations of the Night: Individual Differences in Sleep-Related Experiences and Their Relation to Dissociation and Schizotypy

David Watson — Thu, 26 Mar 2009 09:45:21 PDT

I examined the associations among sleep-related experiences (e.g., hypnagogic hallucinations, nightmares, waking dreams, lucid dreams), dissociation, schizotypy and the Big Five personality traits in two large student samples. Confirmatory factor analyses indicated that (a) dissociation and schizotypy are strongly correlated—yet distinguishable— constructs and (b) the differentiation between them can be enhanced by eliminating detachment/depersonalization items from the dissociation scales. A general measure of sleep experiences was substantially correlated with both schizotypy and dissociation (especially the latter) and more weakly related to the Big Five. In contrast, an index of lucid dreaming was weakly related to all of these other scales. These results suggest that measures of dissociation, schizotypy and sleep-related experiences all define a common domain characterized by unusual cognitions and perceptions.