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An Assessment of the Intraindividual Structure of Depression and Anxiety Symptoms1.08 MB
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Dissertation
An assessment of the intraindividual structure of depression and anxiety symptoms
University of Iowa
Doctor of Philosophy (PhD), University of Iowa
Summer 2024
DOI: 10.25820/etd.007669
Abstract
Objective. The purpose of this work was to determine the structure of depression and anxiety symptoms at the intraindividual level (i.e., within-persons) and to develop a scale to be used in intensive longitudinal research. Use of these methods has increased exponentially during the past decade due to the potential for improved ecological validity of psychopathology assessment. Further, prior work demonstrating meaningful momentary and daily variation in symptoms of depression and anxiety is likely relevant for both the assessment and treatment of depression and anxiety disorders. Despite the growing use of intensive longitudinal methods, little work has been conducted to validate the psychometrics used to measure symptoms of depression and anxiety within these designs. Aim 1 of this dissertation aimed to assess the structure of depression and anxiety symptoms at the intraindividual level, where these symptoms fluctuate within a person over short periods of time. Aim 2 of this dissertation assessed the bidirectional associations of these intraindividual experiences with various psychological factors such as psychosocial stressors, emotional experiences, and personality traits.
Methods. One hundred and sixty-five undergraduate students were recruited from the University of Iowa Department of Psychological and Brain Sciences Research Pool. Participants completed baseline measures of psychopathology, personality, and emotionality as well as screening measures for DSM internalizing disorders. Symptom overreporting and careless or inattentive responding were also evaluated. To be eligible for the intensive longitudinal portion of the study, participants had to show elevated psychopathology scores at baseline free from overreporting and potential inattentive responding at baseline. This resulted in a final sample of 132 participants (71.97% female assigned at birth; 70.45% white-identified, age: M = 18.91 [SD = .94] years) who participated in an intensive longitudinal assessment of daily experiences of depression and anxiety symptoms. The intensive longitudinal portion of the study involved completing three surveys per day for 14 days (42 surveys in total), which assessed symptoms of depression and anxiety, sleep quality, mood, daily stress, and impairment. The symptoms of depression and anxiety were subjected to exploratory factor analyses (EFA) at the within-person level using principal axis rotation with an oblique rotation. This process was both informed by theory and used an empirical approach along with parallel analyses to identify items best suited for the EFA. Resultant factor models were evaluated and compared, and resultant subscale scores were created using the best-fitting factor structure. To address Aim 2, these scores were first decomposed into their interindividual averages and their intraindividual variances. A series of correlational analyses were conducted between the resultant indicators and multiple related constructs (e.g., sleep, stress, internalizing disorders, personality traits) to assess the validity of the factor structure and the resultant scores.
Results. Comparisons of the EFA models indicated that a four-factor solution at the intraindividual level fit the data best, reflecting factors of dysphoria, anxious mood, anxious arousal, and low well-being. These factors showed moderate correlations with one another, and all factors were moderately-to-strongly related to dysphoria. Low well-being, however, was weakly associated with anxious mood and anxious arousal. The interindividual averages of these symptom clusters were correlated with variables such as affect, poor sleep quality, experienced and perceived stress, impairment, internalizing disorders, and personality traits with similar magnitudes and directions found in previous cross-sectional work, apart from relationships among the variables and interindividual experiences with low well-being. Correlations using intraindividual variability revealed different patterns among the variables compared to the interindividual level, and, though these relationships were largely lower in magnitude, elucidated distinct patterns among the process of depression and anxiety symptoms as they related to differences and fluctuations among other psychological factors. While correlations among interindividual dysphoria and anxious mood were similar directionally, differences in magnitude among the constructs at the intraindividual level emerged in their relation to internalizing disorders. Similar to the interindividual level, intraindividual variability in low well-being was largely unrelated to the variables included in this dissertation.
Discussion. While dysphoria and anxious mood are often reflected as general distress at the interindividual level of assessment when measuring symptoms of depression and anxiety, they appear to be more distinct when assessed at the intraindividual level. In evaluating the intraindividual factor structure of daily experiences with symptoms of depression and anxiety, an metric derived from a measure of interindividual experiences with these symptoms was developed. This measure was used to evaluate relationships among the interindividual and intraindividual levels of these symptoms with various psychological constructs such as affect, stress, mental health, and personality, with relationships at the interindividual level largely replicating previous findings and relationships at the intraindividual level assessing more nuanced relationships that elucidates more within-person experiences. Limitations and future directions for research and clinic practice are discussed.
Details
- Title: Subtitle
- An assessment of the intraindividual structure of depression and anxiety symptoms
- Creators
- Brendan Mark Whitney
- Contributors
- Molly Nikolas (Advisor)Isaac Petersen (Committee Member)Amanda McCleery (Committee Member)Emily Thomas (Committee Member)
- Resource Type
- Dissertation
- Degree Awarded
- Doctor of Philosophy (PhD), University of Iowa
- Degree in
- Psychology (Clinical Psychology)
- Date degree season
- Summer 2024
- Publisher
- University of Iowa
- DOI
- 10.25820/etd.007669
- Number of pages
- xi, 118 pages
- Copyright
- Copyright 2024 Brendan Mark Whitney
- Language
- English
- Date submitted
- 07/23/2024
- Description illustrations
- Illustrations, tables, graphs, charts
- Description bibliographic
- Includes bibliographical references (pages 99-118).
- Public Abstract (ETD)
Mental health difficulties related to depression and anxiety are some of the most common and severe in the world. Understanding how they change from day-to-day and how they uniquely impact people is crucial to creating better medical treatments and interventions. Before we can do so, we need to be able to accurately measure these symptoms, both to ensure we are able to monitor change and improvements more closely as well as to better understand what treatments work for which people.
The purpose of this study was to assess momentary changes in depression and anxiety over short periods of time and to create a tool to help measure these symptoms as they change throughout the day. This study also evaluated how fluctuations in these symptoms within a person relate to several factors, such as how people experience emotions, their personality traits, and daily stress. The overall result of this research provided a tool for practitioners and researchers in mental health to use to better understand and treat disorders of anxiety and depression.
- Academic Unit
- Psychological and Brain Sciences
- Record Identifier
- 9984698151302771
Metrics
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