Improving Actigraphy Specificity to Better Inform Insomnia Diagnosis and Treatment Decisions

Access: Use of this item is restricted to the UNT Community
Accurate assessment of sleep-wake patterns is important for sleep researchers and clinicians. Actigraphs are low-cost, non-intrusive, wrist-worn activity detectors used to estimate sleep-wake patterns in a natural environment for several nights. Although actigraphy shows good sensitivity (sleep detection), it has consistently demonstrated poor specificity (wakefulness detection while lying in bed relatively motionless). Because insomnia is characterized by wakefulness in bed, actigraphy may not be a valid objective measure of wakefulness for this group. It is possible that refinement of actigraphy software settings for sleep/wake algorithms might improve specificity. The current studies investigated this hypothesis by comparing wake parameters from 48 combinations of actigraphy settings to determine which sleep/wake algorithms best inform insomnia diagnosis and treatment. In the first study, none of the 48 actigraphy setting combinations consistently discriminated between adults with insomnia (n = 69) and non-insomnia (n = 80) on all three wake parameters, and no setting clearly discriminated between groups for the composite variable, total wake time. Similarly, in the second study, no setting combinations consistently discriminated between adults treated for insomnia (n = 18) and controls with untreated insomnia (n = 26) on all three wake parameters. Although two setting combinations discriminated between groups for the composite …
Date: August 2019
Creator: Francetich, Jade Marie
System: The UNT Digital Library

Organizational Change Development Interventions: Are Multiple Interventions Useful?

Access: Use of this item is restricted to the UNT Community
The effects of multiple interventions in organizational development change were studied in a comprehensive meta-analytic review. Thirteen organizational interventions were assessed on five outcome variables based upon previous research of six major meta-analytic reviews. Findings based on 138 studies indicated that there were no significant effects of multiple interventions on positive organizational change as opposed to individually implemented interventions. The findings are not congruent with previous findings of organizational development change, and possible issues surrounding these differences are discussed.
Date: August 2005
Creator: Smith, Lindsay C.
System: The UNT Digital Library

Organizational development: A comparison of individual and organizational level change.

Access: Use of this item is restricted to the UNT Community
Organizational change and development (OCD) has been studied by researchers to identify the effectiveness of change initiatives. Because of the broad scope of interventions in OCD, these studies have covered a range of areas including multiple interventions and the methodological rigor used by researchers. However, few have looked at organizational versus individual change within an organization, to examine whether individual change is more effective than organizational change. The purpose of this study is to determine if organizational change occurs in a top down or bottom up manner. A meta-analysis was conducted using 238 field experiments. Each study was coded for intervention and organizational outcome and for individual or organizational level variables. Effect sizes were calculated for each study, each level, and each level by intervention and outcome measure. Results indicate that while OCD interventions overall had a moderate effect size, the level of intervention or outcome was not a moderating variable.
Date: August 2005
Creator: Barnett, Michelle L.
System: The UNT Digital Library

Modeling Marijuana Use Willingness and Problems as a Function of Social Rejection and Social Anxiety

Access: Use of this item is restricted to the UNT Community
Marijuana is the second most commonly used substance in the US. A growing literature suggests that socially anxious individuals use marijuana to manage their symptoms in social situations, which may explain why they are also more likely to experience problems. Unfortunately, the majority of the literature is based on research conducted with adult samples or the co-occurrence of diagnoses in adolescent samples. The proposed study sought to test the link between social anxiety (SA) and proxies for ‘real-time' marijuana use behaviors (i.e., use willingness) as well as use-related problems among adolescents. Participants were 69 adolescents (15-17; 55% female) recruited from the community reporting any lifetime marijuana use. Participants were randomly assigned to a novel social rejection or neutral laboratory task and completed measures of SA, marijuana use frequency, and related problems. Consistent with adult findings, main effects of SA and experimental condition on marijuana use willingness were expected to be qualified by an interaction in which the greatest marijuana use willingness would occur among high SA youth post-rejection (H1), SA would be positively related to marijuana use problems (H2), and among adolescents in the rejection condition, marijuana use willingness would be positively correlated with use problems (H3). Only H2 was …
Date: May 2019
Creator: Cloutier, Renee
System: The UNT Digital Library

Independence of Mania and Depression across 4 Years in Bipolar Disorder

Access: Use of this item is restricted to the UNT Community
If mania and depression are part of the same pathological processes, one would predict that episodes of one prospectively increase the odds of episodes of the other. The aim of the present study was to test this hypothesis. For comparison purposes, their relationship was contrasted to the relationship between mania and periods of psychosis. Exploratory analyses also tested the degree to which episodes of each occur with greater frequency over time (i.e., kindling). Participants for the present study came from the Suffolk County Mental Health Project (N = 628), a study of first-admission patients with psychosis. Of these participants, 144 met diagnostic criteria for bipolar I disorder and were analyzed for the current study. Results indicated that mania in a given month predicted depression the following month, even after controlling for other symptoms. The reverse, however, was not the case. Mania and psychosis, in contrast, were found to be robust predictors of one another from month to month. Effects were not due to treatment or demographic differences. These findings provide evidence that mania and depression are weakly related. In contrast, mania and psychosis are more closely linked. Findings are consistent with suggestions that psychiatric nosology regroup mania more closely with …
Date: May 2019
Creator: Bennett, Charles B.
System: The UNT Digital Library

Sex and Gender Differences in Perceived and Actual Leadership Performance: Self- and Subordinate Views

Access: Use of this item is restricted to the UNT Community
The purpose of this study was to examine how male and female leaders view their own effectiveness as compared to their objective performance. This study also examined sex and gender differences in subordinate's views of male and female leaders. Forty-two mixed-sex groups led by appointed male and female leaders were observed to assess objective and perceived leader effectiveness. Gender role of participants was assessed using the Bem Sex Role Inventory (BSRI). No sex or gender differences were found in objective leadership effectiveness. An unexpected finding was that male and female leaders perceived themselves accurately as leaders. Significant differences were found in the way male subordinates rated men and women leaders when taking into account gender role. Results indicated that the study of gender bias in leadership is complex and should be examined in conjunction with gender role. Social role theory helps to explain this bias.
Date: May 2003
Creator: Rivero, Arlene Jean
System: The UNT Digital Library