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"Fischer, Ian"
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The Conditional Entropy Bottleneck
Much of the field of Machine Learning exhibits a prominent set of failure modes, including vulnerability to adversarial examples, poor out-of-distribution (OoD) detection, miscalibration, and willingness to memorize random labelings of datasets. We characterize these as failures of robust generalization, which extends the traditional measure of generalization as accuracy or related metrics on a held-out set. We hypothesize that these failures to robustly generalize are due to the learning systems retaining too much information about the training data. To test this hypothesis, we propose the Minimum Necessary Information (MNI) criterion for evaluating the quality of a model. In order to train models that perform well with respect to the MNI criterion, we present a new objective function, the Conditional Entropy Bottleneck (CEB), which is closely related to the Information Bottleneck (IB). We experimentally test our hypothesis by comparing the performance of CEB models with deterministic models and Variational Information Bottleneck (VIB) models on a variety of different datasets and robustness challenges. We find strong empirical evidence supporting our hypothesis that MNI models improve on these problems of robust generalization.
Journal Article
Happiness in US military veterans: Results from a nationally representative study
In line with the US Department of Veterans Affairs’ adoption of a Whole Health approach to healthcare, there has been growing interest in factors linked to veterans’ perceptions of well-being. To date, no known study has examined levels and correlates of perceived happiness in this population. To examine this question, we analyzed data from the National Health and Resilience in Veterans Study, which surveyed a nationally representative sample of 4,069 US military veterans. Overall, veterans reported mean happiness scores of 5.41 out of 7. Greater purpose in life was the strongest correlate of happiness, followed by lower severity of depressive symptoms, and higher optimism, emotional stability, and resilience. Among veterans who screened positive for depression, those who scored higher on measures of optimism, emotional stability, and resilience reported greater happiness. Interventions to leverage these modifiable psychosocial characteristics may help promote happiness and subjective well-being in this population.
Journal Article
Co-occurring Chronic Pain and PTSD Among US Military Veterans: Prevalence, Correlates, and Functioning
The prevalence of co-occurring chronic pain and posttraumatic stress disorder (PTSD) has yet to be established in a nationally representative sample of US veterans, and little is known about the individual contributing roles of these disorders to the psychiatric and functional burden of this comorbidity.
To determine the prevalence of chronic pain, PTSD, and co-occurring chronic pain and PTSD, and psychiatric comorbidities and psychosocial functioning in these groups.
Data were analyzed from the National Health and Resilience in Veterans Study, which surveyed a nationally representative sample of US veterans.
Veterans (n=4069) were classified into four groups: control (i.e., no PTSD or chronic pain), chronic pain only, PTSD only, and co-occurring chronic pain and PTSD.
A probable PTSD diagnosis was established using the PTSD Checklist for DSM-5, and a chronic pain diagnosis using a self-report item that queried health care professional diagnoses. Psychiatric and functional status were assessed using the Patient Health Questionnaire-4, Alcohol Use Disorders Identification Test, Screen of Drug Use, Suicide Behaviors Questionnaire-Revised, Short Form Health Survey-8, Brief Inventory of Psychosocial Functioning, and Medical Outcomes Study Cognitive Functioning Scale.
A total of 3.8% of veterans reported both probable PTSD and a diagnosis of chronic pain. Relative to veterans with chronic pain alone, those with co-occurring chronic pain and probable PTSD were more likely to screen positive for psychiatric disorders (odds ratios [ORs]=2.59-9.88) and scored lower on measures of psychosocial functioning (Cohen's ds=0.38-1.43). Relative to veterans with probable PTSD only, those with co-occurring chronic pain and probable PTSD were more likely to have attempted suicide (OR=4.79; 95%CI, 1.81-12.69).
Results underscore the importance of whole health care that considers a broad range of health and functional domains in the assessment and treatment of co-occurring chronic pain and PTSD in veterans.
Journal Article
Predicting symptoms of anxiety and depression in patients living with advanced cancer: the differential roles of hope and optimism
PurposePsychological distress is related to poorer functioning and reduced quality of life in patients with advanced cancer and may have untoward influences on treatment decisions. Current research on factors associated with this distress is limited, making targeted interventions to reduce it suboptimal. We examined the relationships between two goal-related expectancies and two of the most common symptoms of psychological distress in patients living with advanced cancer: anxiety and depressive symptoms.MethodsPatients with advanced gastrointestinal cancer, colorectal cancer, lung cancer, or melanoma (N = 84) completed measures of anxiety, depressive symptoms, optimism, hope, and prediction for 12-month survival. Oncologists provided prediction for patient 12-month survival and patient performance status.ResultsHope, but not optimism, was associated with less severe depressive symptoms (β = − 0.42). Conversely, optimism, but not hope, was associated with less severe anxiety symptoms (β = − 0.36).ConclusionsHope and optimism appear to be associated with different aspects of psychological distress in patients living with advanced cancer. This may be explained by different appraisals of the uncertainty and distress that are associated with living with advanced-stage cancer. Hope- or optimism-focused interventions can be tailored to help alleviate specific aspects of psychological distress among these patients.
Journal Article
Barriers to Mental Health Care in US Military Veterans
BackgroundMilitary veterans often encounter multiple obstacles to mental health care, such as stigma, practical barriers (e.g., high cost), and negative beliefs about mental health care. To date, however, nationally representative data on the prevalence and key correlates of these barriers to care are lacking. Such data are critical to informing population-based efforts to reduce barriers and promote engagement in mental health treatment in this population.MethodsData were analyzed from the National Health and Resilience in Veterans Study, which surveyed 4,069 US veterans, 531 (weighted 15.0%) of whom screened positive for a mental disorder but never received mental health treatment. Multivariable logistic regression and relative importance analyses were conducted to identify key predisposing, enabling, and need-based factors associated with endorsement of stigma, instrumental barriers, and negative beliefs about mental health care.ResultsA total 47.1% of veterans endorsed any barrier to care, with 38.7% endorsing instrumental barriers to care, 28.8% perceived stigma, and 22.0% negative beliefs about mental health care. Lower purpose in life, grit, and received social support were most consistently associated with these barriers to care.ConclusionsNearly half of US veterans with psychiatric need and no history of mental health treatment report barriers to care. Modifiable characteristics such as a low purpose in life, grit, and received support were associated with endorsement of these barriers. Results may help inform resource allocation, as well as prevention, psychoeducation, and treatment efforts to help reduce barriers and promote engagement with mental health services in this population.
Journal Article
Posttraumatic Growth in U.S. Military Veterans: Results from the National Health and Resilience in Veterans Study
Despite increasing recognition that positive psychological changes or posttraumatic growth (PTG) may develop after highly stressful or traumatic events, contemporary population-based data on the epidemiology of PTG in high-risk samples such as U.S. military veterans are lacking. Additionally, in light of emerging evidence suggesting an 8-factor model of posttraumatic stress disorder (PTSD) symptoms, an up-to-date characterization of how these symptom clusters relate to PTG can help inform efforts to help promote PTG. Data were analyzed from the 2019–2020 National Health and Resilience in Veterans Study (NHRVS), which surveyed a nationally representative sample of 3,847 trauma-exposed U.S. veterans. Participants completed assessments of potentially traumatic events, PTSD symptoms, and PTG, as well as a broad range of sociodemographic, military, trauma, health, personality, and psychosocial characteristics. Results revealed that 63.2% of trauma-exposed veterans and 86.4% of veterans who screened positive for PTSD endorsed moderate-or-greater PTG; these prevalences are higher than those reported in an independent U.S. veteran sample in 2011 (50.1% and 72.0%, respectively). An inverted U-shaped association was observed between PTSD symptom severity and PTG levels, with scores of 31 to 51 on the PTSD Checklist for DSM-5 associated with the highest likelihood of PTG. Intrinsic religiosity and internally- and externally-generated intrusive symptoms of PTSD were identified as the strongest correlates of PTG. Results suggest that prevention and treatment efforts to mitigate severe PTSD symptoms, and help promote intrinsic religiosity, and more deliberate and organized rumination about traumatic experiences may help foster PTG in veterans.
Journal Article
Negative aging stereotypes in U.S. military veterans: results from the National Health and Resilience in Veterans Study
U.S. military veterans are an average 20 years older than non-veterans and have elevated rates of certain health conditions. While negative aging stereotypes have been linked to increased risk for various health conditions, little is known about the prevalence and correlates of these stereotypes in this population. Using data from a nationally representative sample of 4,069 U.S. veterans surveyed between 11/19 and 3/20, we examined (1) the current prevalence of negative aging stereotypes related to physical, mental, and cognitive health and (2) sociodemographic, health, and psychosocial factors associated with these stereotypes. Multivariable regression and relative weight analyses were conducted to identify independent correlates of negative aging stereotypes. Results revealed that 82.3%, 71.1%, and 30.0% of veterans endorsed negative aging stereotypes related to physical, cognitive, and emotional health, respectively. Older age (36.6% relative variance explained), grit (23.6%), and optimism (17.5%) explained the majority of the variance in negative age stereotypes related to physical aging; grit (46.6%), openness to experiences (31.5%), and older age (15.1%) in negative age stereotypes related to cognitive aging; and emotional stability (28.8%), purpose in life (28.8%), and grit (25.3%) in negative age stereotypes related to emotional aging. This study provides an up-to-date characterization of the prevalence and correlates of negative aging stereotypes in U.S. veterans. Results underscore the importance of targeting key correlates of negative aging stereotypes, such as lower grit, as part of efforts to promote health and functioning in this population.
Journal Article
Psychological Resilience in U.S. Military Veterans: Results from the 2019–2020 National Health and Resilience in Veterans Study
Following exposure to traumatic life events, most individuals are psychologically resilient, and experience minimal-to-no symptoms of posttraumatic stress, major depressive, or generalized anxiety disorders. To date, however, most research has focused on factors associated with adverse post-trauma mental health outcomes rather than understanding those associated with psychological resilience. In particular, little is known about factors associated with psychological resilience in veterans, despite their high rates of trauma exposure, such as combat and military sexual trauma. To address this gap, we used a discrepancy-based psychiatric resilience (DBPR) analytic approach to operationalize psychological resilience, and to identify modifiable health and psychosocial factors associated with resilience in a nationally representative sample of U.S. veterans (N = 4,069). DBPR scores were computed by regressing a composite measure of distress (posttraumatic stress, major depressive, and generalized anxiety disorder symptoms) onto measures of adverse childhood experiences, combat exposure, military sexual trauma, and cumulative potentially traumatic events (e.g., natural disaster, life-threatening illness/injury). Psychological resilience was operationalized as lower actual, relative to predicted, composite distress scores. Results revealed that greater emotional stability (22.9% relative variance explained [RVE]) and mindfulness (13.4% RVE), lower likelihood of lifetime histories of MDD or PTSD (12.8% RVE), greater purpose in life (11.9% RVE), and lower severity of somatic symptoms (10.8% RVE) explained the majority of the variance in resilience scores (total R2 = 0.40). Taken together, results of this study illustrate the utility of a DBPR score approach to operationalizing psychological resilience to traumatic stress in U.S. veterans, and identify several modifiable health and psychosocial factors that can be targeted in prevention and treatment efforts designed to bolster resilience in this population.
Journal Article
“If your feelings were hurt, I’m sorry…”: How Third-Year Medical Students Observe, Learn From, and Engage in Apologies
BackgroundApologies may play a significant role in medical care, especially in the context of patient safety, medical error disclosure, and malpractice. Studies have shown that when state laws, institutional policies, and individual skills align—including the ability to offer a sincere apology—patients and families benefit. However, little is known about how, and under what conditions, physicians offer apologies in day-to-day care. Even less is known about what medical students learn about apologies from observing their superiors in these settings.ObjectiveCharacterize third-year medical students’ experiences of observing and engaging in apologies.DesignQualitative descriptive analysis of student professionalism narratives.ParticipantsThird-year medical students at Indiana University School of Medicine.ApproachA search of 7,384 unique narratives yielded 238 with apologies. A rubric based on four key elements of genuine apologies ((1) acknowledgement, (2) explanation, (3) regret/remorse, and (4) reparation) was used to classify the kind of apology offered. Apology completeness, impact, and timing were also coded.Key ResultsSeventeen percent of all apologies were complete (i.e., contained all four elements). Over 40% were coded as incomplete or “non-apology” apologies (i.e., those with only the first two elements). A significant relationship between apology completeness and positive student experience was found. Most apologies were offered by the attending physician or resident to patients and family members. Students were generally positive about their experiences, but one in five were coded as negative. Some students were distressed enough to offer apologies on behalf of the faculty. Apology timing did not make a significant difference in terms of student experience.ConclusionsFew education programs target apologies in the context of routine practice. With little formal instruction, students may rely on adopting what their seniors do. Faculty have an important role to play in modeling the apology process when harms—both great and small—occur.
Journal Article