Digital Commons Network^™

Predicting Healthcare-Seeking For Childhood Diarrhea Across Low- And Middle-Income Countries, Madi Baltagulov

Public Health Theses

Healthcare-seeking behavior (HSB) for childhood diarrhea is a central but persistently uncertain input for rotavirus burden models and vaccine cost-effectiveness analyses. Demographic and Health Surveys (DHS) provide the only nationally representative measurements, yet they are expensive and absent from the majority of low- and middle-income countries (LMICs). This thesis asks whether publicly available country-level indicators can substitute for DHS data when survey estimates are unavailable.Using the most recent DHS conducted between 2011 and 2024 in 51 LMICs (78,008 children under five with diarrhea), I fit a multilevel modified Poisson regression and a two-stage random-effects meta-regression with four World Bank moderators: …

Implementation Of Digital Interventions To Address Alcohol Use In Primary Care: A Scoping Review, Sean Becker

Public Health Theses

The development and implementation of digital interventions in the identification andmanagement of unhealthy alcohol use (i.e., the spectrum of consumption including at-risk alcohol use and alcohol use disorder) in the primary care setting has seen numerous advancements in recent years. Such rapid change makes it difficult to understand and assess the current state of the literature as it relates to these implementation topics. To better understand the broader research landscape, we (SB, Advised by EJE and BK and with collaboration from AG) conducted a scoping review to: 1) characterize the focus, components, and mode of digital interventions for targeting alcohol …

Dietary, Physical Activity, Mental Health And Substance Use Among Adolescents In American Samoa: A Cross-Sectional Study, Arwen Chen

Public Health Theses

Adolescent mental health is an important public health concern in American Samoa, but limited research has examined how modifiable health behaviors relate to mental health outcomes in this population. This cross-sectional study examined associations of dietary patterns, sugar-sweetened beverage (SSB) consumption, and physical activity with depressive symptoms, anxiety symptoms, and substance use among 449 high school students in American Samoa. Depressive symptoms, anxiety symptoms, substance use, diet, and physical activity were assessed using self-reported survey measures, including the Patient Health Questionnaire-9 for Adolescents (PHQ-9A), Generalized Anxiety Disorder-7 scale (GAD-7), Dietary Screener Questionnaire (DSQ) items, and the Physical Activity Questionnaire for …

Stigma, Coping & Resilience Among Hiv+ Pwid In St. Petersburg, Rf, Gabrielle Bogut

Public Health Theses

Russia and the other countries that comprised the Soviet Union constitute the one region in which the HIV epidemic continues to expand. Unlike most other regions, more than a quarter of HIV cases in Russia resulted from unsafe injection among people who inject drugs (PWID), and St. Petersburg is among the cities with the highest rates and case counts of HIV. Our study sought to identify actionable psychosocial characteristics influencing receipt of antiretroviral therapy (ART) in PWID. This study assessed survey results from 225 HIV-positive individuals recruited from a Russian NGO that provides PWID with harm reduction services. Individuals were …

Discrimination And Stress Recovery In Romantic Couples: A Dyadic Analysis Of Vagal Rebound And Stress Appraisal, J. Doris Chi

Public Health Theses

Background: Perceived discrimination is a chronic stressor linked to adverse psychological and physical health outcomes, yet less is known about how it shapes parasympathetic recovery after acute stress within close relationships. The present study examined the direct and vicarious effects of discrimination on vagal rebound and stress appraisal following a social-evaluative speech task, and whether these associations varied by identity attribution.

Methods: Data were drawn from 188 romantic couples (N = 376) from the New Haven area. Participants completed measures of everyday discrimination prior to the laboratory visit and stress appraisal before and after the speech task. Respiratory sinus arrhythmia …

Ethics Training For Community Researchers Engaged In Participatory Research: An Analysis Investigating Current Practices In Low-Income Countries, Chioma Chukwunedu

Public Health Theses

Participatory Research (PR) involves individuals affected by a research problem as active collaborators rather than passive subjects. While this approach emphasizes ethical and contextually relevant practices, existing literature suggests that ethics training for community researchers in low-income countries is inconsistently implemented and often not culturally adapted. This study examines how ethics training is currently provided to community researchers engaged in PR in low-income countries.A secondary analysis was conducted using manuscripts identified through a prior systematic review of PR studies in low-income settings. Corresponding authors of included studies were invited to complete an online Qualtrics survey regarding ethics training, participatory research …

The Effect Of Flood Risk Perception On County-Level Excess Mortality Due To Flooding In The U.S., Jane Elise Fortna

Public Health Theses

Introduction: Flood events due to heavy precipitation, hurricanes, rising sea levels, and overflowing rivers are increasing under climate change, resulting in both direct and indirect health impacts. This study investigates the relationship between excess flood mortality and flood risk perception at the U.S. county level. Methods: This study utilizes nationwide, county-level flood mortality data from 2018-2020 and flood risk perception survey data from 2024. We applied a generalized linear model to examine the association between the proportion worried about flooding and the excess flood mortality, while controlling for flood hazard exposure, poverty, disability, health uninsurance rate, and unmeasured spatial confounding …

Intergenerational Meaning-Making In Cambodian Americans, Caitlin Gojuk

Public Health Theses

Background: Cambodian Americans face high psychological distress yet remain underrepresented in research, especially second-generation individuals. Intergenerational trauma, stigma, and family dynamics shape mental health understanding and expression. Objective: This study examines how Cambodian American young adults make sense of mental health and distress through cultural identity, family relationships, and inherited meanings of trauma. Methods: In-depth semi-structured interviews were conducted with six second-generation Cambodian American young adults residing in Massachusetts, United States. Participants completed brief measures of depression and anxiety symptoms (PHQ-8; GAD-7) to provide a descriptive context. Interviews were analyzed using inductive thematic analysis informed by relational, narrative, and ecological …

A Mendelian Randomization Study Of Maternal Thyroid Function And Cerebral Palsy, Yuewen Ge

Public Health Theses

Cerebral palsy (CP) is a neuromotor disorder that is strongly associated with adverse perinatal conditions. Thyroid dysfunction in pregnancy was suggested to affect CP risk in a few cohort studies, but the evidence is not yet conclusive. We conducted a two-sample MR study to explore the effect of thyroid function on the risk of CP in offspring, and preterm birth as a potential mediator. Genetic instruments for hyperthyroidism and hypothyroidism were obtained from a large European genome-wide association study (GWAS) by Sakaue et al. (2021), instruments for free thyroxine (FT4) and thyrotropin (TSH) were derived from the ThyroidOmics Consortium, and …

Clostridioides Difficile Infection Trends And Treatment Concordance With Idsa/Shea Guidelines In The Connecticut Emerging Infections Program Catchment Area, 2011-2024, Rachael Hopkins

Public Health Theses

Background: Clostridioides difficile infection (CDI) is a gastrointestinal infection causing colon inflammation, diarrhea, and potential life-threatening complications. In 2021, treatment guidelines for CDI were updated by the Infectious Diseases Society of America (IDSA) and the Society for Healthcare Epidemiology of America (SHEA). This study analyzed Connecticut Emerging Infections Program (EIP) data to assess CDI incidence trends (2011-2024) and evaluate physician concordance with 2021 guidelines for incident cases (2022-2024). Methods: The Connecticut EIP conducted CDI surveillance in New Haven County (2011-2023) and South Central and Naugatuck planning regions (2024). Incidence rates were calculated using census data. Concordance was defined as treatment …

Cost-Effectiveness Analysis Of Twice-Yearly Injectable Lenacapavir Versus Daily Oral Prep For Hiv Prevention Among Men Who Have Sex With Men In China, Xueqing Guo

Public Health Theses

Men who have sex with men (MSM) remain a key at-risk population in China’s HIV epidemic while the real-world effectiveness of daily oral pre-exposure prophylaxis (PrEP) among MSM has been limited by low uptake and suboptimal drug adherence. Lenacapavir, a first-in-class capsid inhibitor administered twice yearly, emerged as a highly efficacious, long-acting prevention strategy with the potential to reduce drug burdens associated with current PrEP strategy. However, its high price ($28,000 per patient per year) raises major affordability concerns, and its economic value in China remains understudied. This study aimed to evaluate the cost-effectiveness of lenacapavir compared with daily oral …

Role Of Functional Social Support In Adherence To Hypertension Therapy: A Community-Based Study In Nepal, Shirish Gurung

Public Health Theses

Introduction: Despite evidence that adherence to hypertension therapy is associated with improved blood pressure control and health outcomes, adherence rates remain suboptimal. This study aims to examine the association between perceived functional social support and adherence to hypertension therapy in Nepal.

Methods: This study utilized cross-sectional baseline data collected from an ongoing community health worker-led hypertension prevention and control trial in Sindhupalchok District, Nepal. Adherence to hypertension therapy was measured using the Hill-Bone High Blood Pressure Therapy Compliance Scale, and perceived functional social support was measured using the Medical Outcomes Study Social Support Survey. Modified Poisson regression with robust standard …

Water Resource Governance And Health Equity In Angola, Mads Harner

Public Health Theses

AbstractBackground: Angola is confronting a set of intertwined challenges including water insecurity, increasing climate variability, and deep structural inequality that together intensify the burden of waterborne and water-related diseases (Lombana Cordoba et al., 2021; World Health Organization, 2025). Roughly half of the population does not have reliable access to safe drinking water, and gaps in sanitation and hygiene infrastructure, especially in peri-urban and rural areas, facilitate the spread of illnesses such as cholera, diarrheal diseases, and malaria (UNICEF Angola, 2025; Moreira et al., 2012). These issues are further exacerbated by drought and broader climate variability, and underlying them are historical …

Using The Behavior Change Wheel To Understand The Role Of Antimicrobial Stewardship Programs, Siqi Jiang

Public Health Theses

Objectives: This review aimed to summarize recent antimicrobial stewardship programs (ASPs) implemented in pediatric outpatient settings and analyze how these interventions influence appropriate antibiotic use.Methods: PubMed and Scopus were searched for studies published between 2016 and 2026 globally. Studies were included if they evaluated an antimicrobial stewardship intervention in a pediatric outpatient setting. Only English studies are included. Studies that describe the results of implementations and policies related to ASP are included, including randomized controlled trials, quasi-experiments, natural experiments, quality improvement studies and observational studies, and longitudinal studies. Interventions in selected articles were analyzed using the COM-B (Capability, Opportunity, Motivation-Behavior) …

Family-Related Stressors And Mental Health Among Internally Displaced Young Adults In Mozambique: A Mixed-Methods Study With Implications For Global Mental Health Interventions, Jaspreet Kandola

Public Health Theses

Mental health outcomes among displaced populations are shaped by post-displacement stressors, yet the role of family dynamics, specifically, remains insufficiently understood. This study examines how family-related stressors are associated with mental health among internally displaced young adults in Nampula Province, Mozambique. Using a convergent parallel mixed methods design, this study integrated survey data from 601 participants with qualitative data from in-depth interviews with a subsample of 16 participants. Quantitative analyses showed that family separation and concern for family members in conflict zones were associated with higher posttraumatic stress disorder (PTSD) symptoms, with family separation also linked to higher anxiety and …

Kinetics Of Antibody Responses To Hookworm Excretory/Secretory Products In A Hamster Model Of Infection And Cure, Jacquelyn Kauffman

Public Health Theses

Hookworms are a major global health burden in resource-limited settings despite ongoing control programs. This makes understanding host immune responses to infection and treatment critical to improve diagnostics and interventions. This study investigates the long-term kinetics of antibody responses following infection with Ancylostoma ceylanicum in a hamster model. Over a one-year study, groups of six hamsters were assigned to uninfected, infected, or infected then treated groups, with antibody responses measured using ELISAs. All infected animals had elevated IgG, IgM, and IgA responses by day 21 post infection. Mebendazole-treated hamsters had significantly reduced, but not eliminated, antibody levels, with IgM responses …

Nowcasting Dengue Cases In Poor Surveillance Nations Using Meteorology And Climate-Similar Countries, Hanna Kim

Public Health Theses

Dengue fever poses a growing public health burden across the Caribbean, yet surveillance infrastructure remains inconsistent and timely outbreak detection in data-poor nations becomes limited. This study investigates whether shared meteorological patterns between Caribbean countries can be leveraged to nowcast dengue activity in low-surveillance settings using climate-matched, well-surveilled nations as epidemiological proxies. Weekly and monthly dengue case data for six countries, the Dominican Republic, Jamaica, Puerto Rico, Trinidad and Tobago, Cuba, and Haiti, were extracted from the OpenDengue database for 2005–2024, and satellite-derived climate data were obtained from the NASA POWER API. Pairwise climate correlations revealed strong temperature synchrony across …

Indoor Environmental Quality Perceptions And Self-Reported Symptoms Among West Haven Va Healthcare Employees, Joseph Hyong Kim

Public Health Theses

Background: Indoor environmental quality in workplace settings influences worker well-being, yet the relationship between perceived workplace environment and reported symptoms remains less well characterized in heterogeneous healthcare settings. This study describes perceived workplace environmental quality and self-reported symptoms among employees at the West Haven Veterans Affairs (VA) Medical Center.

Methods: An observational, cross-sectional study was conducted of VA employees across clinical and non-clinical roles to assess perceived work environment, symptoms and indoor exposures using an electronic survey and personal and area air monitoring of indoor volatile organic compounds (VOCs) and viruses. Perceived workplace environmental quality was assessed using the MM-40 …

Pediatric Rheumatic Heart Disease Screening For Secondary Antibiotic Prophylaxis: An Explainable Shannon Energy Approach Using Heart Phonocardiogram In Northeast Brazil, Zhuohui Lin

Public Health Theses

Rheumatic Heart Disease (RHD), caused by Group A Streptococcus (GAS), remains a significant global health burden, particularly among children in low- and middle-income countries. Untreated GAS infection can lead to acute rheumatic fever and subsequent chronic valvular damage of RHD, such as mitral valve (MV) regurgitation. Hence, early detection is critical for the administration of Secondary Antibiotic Prophylaxis to prevent disease progression. Although deep learning models demonstrate high diagnostic accuracy, limited explainability restricts clinical adoption, especially in resource-limited settings. In this proof-of-concept study, we evaluated Shannon energy (SE) transformation as a proxy to differentiate holosystolic murmurs associated with RHD-related mitral …

Climate, Land Use, And Lyme Disease Risk In The United States, Mohan Li

Public Health Theses

Lyme disease is the most common vector-borne bacterial infection in the United States. It remains an important public health concern due to its high disease burden, expanding geographic distribution, and complex transmission cycle. Climate change is frequently regarded as a driver of Lyme disease emergence, as many previous studies suggested. However, ongoing debate about the magnitude and mechanisms of climate effects complicates the interpretation of this relationship. This review synthesizes evidence on how climate influences Lyme disease through both direct and indirect pathways, with a focus on studies relevant to the United States and North America.Climate directly affects Lyme disease …

Optimizing Positivity Cutpoints Using Validated Assessment Tools For Osteoporosis And Sarcopenia In Aging People Living With Hiv In Peru, Joselito Malca Hernandez

Public Health Theses

AbstractBackground: People living with HIV (PWH) are at increased risk of osteoporosis and sarcopenia, yet access to gold-standard diagnostic tools remains limited in many settings. Low-cost screening tools such as OST, SCORE, and SARC-F offer practical alternatives, but optimal cutpoints and their implications for clinical decision-making in PWH are not well defined.

Methods: We conducted a secondary analysis of cross-sectional data from 229 PWH aged ≥45 years receiving care in Lima, Peru. Osteoporosis was defined using DXA among postmenopausal women and men ≥50 years, and sarcopenia using AWGS-2019 and EWGSOP2 criteria. We evaluated the diagnostic performance of OST, SCORE, their …

Maternal Sleep, Sleep Medication Use, And Birth Outcomes: A Pilot Study Of The Pregnancy, Environment, And Child Health (Peach) Cohort, Samantha Lydell

Public Health Theses

Pregnancy is often a period of poor sleep quality. Previous research has linked reduced sleep quality and difficulty sleeping during pregnancy to adverse maternal and fetal outcomes. However, little is known about how sleep medication use may influence these associations. This pilot study examines the relationships between poor sleep, sleep medication use, and birth outcomes in the Pregnancy, Environment, and Child Health (PEACH) cohort. This study included 136 participants from the PEACH cohort linked to Yale New Haven Health delivery records. Poor sleep and sleep medication use were self-reported. Outcomes were gestational age at birth (days) and birth weight (grams). …

Understanding The Influence Of Hiv Status On Perceived Barriers To Reproductive Care For Pregnant Haitian Women: A Framework-Guided Qualitative Analysis, Olivia Mccarthy

Public Health Theses

Background: Haiti has the highest maternal mortality rate in Latin America and the Caribbean, where pregnant women face substantial structural, social, and economic barriers to care. Women living with HIV encounter additional challenges, including stigma, breaches of privacy, and discrimination within healthcare settings. Although prior research has examined maternal health and HIV related stigma in Haiti, little is known about how HIV status differentially shapes pregnant women’s perceptions of barriers to maternal healthcare.Methods: This study draws on data from seven focus groups conducted in rural communities in Haiti’s Centre Department between 2018 and 2019. Participants included 65 pregnant women, representing …

Telehealth Adaptation Of Bright Bodies Program, A Pediatric Intensive Lifestyle Intervention For Obesity: Caregiver Experiences And Implications For Future Implementation, Xiayu "Katniss" Ni

Public Health Theses

Introduction: The Virtual Bright Bodies Program is a telehealth adaptation of Yale's evidence-based family-based intensive lifestyle intervention targeting pediatric obesity, delivered through video conferencing during and following the COVID-19 pandemic. This retrospective cross-sectional study evaluated caregiver experiences with the telehealth-adapted program among 25 caregivers of children aged 7-16 years who completed a post-program survey.

Method: Caregiver perceptions were assessed using the adapted Telehealth Satisfaction Questionnaire (TSQ, 13 items), the adapted Telemedicine Satisfaction and Usefulness Questionnaire (TSUQ, 4 items), and the Acceptability of Intervention Measure (AIM, 4 items). Quantitative data were analyzed descriptively, followed by exploratory subgroup analyses examined whether acceptability …

Triangulating Clinical Guideline Recommendations To Map The Standard Of Care For Hypertensive Disorders Of Pregnancy During Pregnancy And Postpartum, Caralie Price

Public Health Theses

Hypertensive disorders of pregnancy (HDP) are one of the leading causes of maternal morbidity and mortality in the United States. HDP represent a severe health equity issue and present concerns for the health of mother and child, highlighting the importance of early detection and management. This paper systematically documented current clinical practice guidelines from the American College of Obstetricians and Gynecologists (ACOG) and the Society for Maternal-Fetal Medicine (SMFM) for preventing, identifying, and treating HDP during the prenatal, intrapartum, and postpartum periods. ACOG provides recommendations for HDP across different types of clinical guidance documents. Overall, 60 recommendations were extracted across …

Characterization Of Tick Exoproteins Interacting With Anaplasma Phagocytophilum, Yilei Qin

Public Health Theses

Anaplasma phagocytophilum (Ap) is an Ixodes-transmitted obligate intracellular bacterium thatinfects neutrophils and causes human granulocytic anaplasmosis. Ap alternates between an infectious dense-cored (DC) form and a replicative reticulate cell (RC) form, and successful transmission depends on coordinated interactions at the vector–pathogen interface. Tick extracellular and secreted proteins (the tick exoproteome) likely contribute to Ap survival and transmission, yet many proposed tick factors remain computationally annotated with limited experimental validation. In this thesis, I prioritize candidate tick exoproteins, identified from yeast- display screens using whole Ap organisms, and evaluate them using a two-step validation strategy. First, I quantify tissue-specific expression of …

Protecting Older Individuals From Age Discrimination Harming Psychological Well-Being: Role Of Neighborhood Cohesion, Tongyu Qiu

Public Health Theses

Age discrimination is known to harm older adults’ mental health, yet factors that may protect against this harm have received little attention. Prior studies have focused primarily on individual-level factors rather than community-level characteristics, such as neighborhood cohesion, which may be more amenable to large-scale interventions and policies. To our knowledge, no prior study has examined whether neighborhood cohesion buffers the association between age discrimination and worse psychological well-being in older adults. Participants aged 60 years and older were drawn from the Midlife in the United States (MIDUS) study. We hypothesized that baseline age discrimination would predict worse psychological well-being …

Status, Inclusion, And Self-Esteem In Daily Life: Examining Moderation By Social Anxiety, Dylan Schnur

Public Health Theses

Prior work has shown a distinct pattern in how social feedback shapes self-belief and self-esteembetween individuals with and without social anxiety disorders (SAD). EMA-type studies have proven to be valuable because these types of studies can capture differences in cognition, health, and behavior across forms of psychopathology between- and within individuals. To our knowledge, no prior studies akin to EMA have examined between- and within-person associations of status and inclusion on self-esteem and moderation by social anxiety when positive and negative feedback, regarding these traits, are experienced. Across this 21-day ecological momentary assessment study, participants (N = 175, 12,021 observations) …

Effectiveness Of The Release Of Wmel Wolbachia-Infected Aedes Aegypti Mosquitoes On The Incidence Of Chikungunya In Campo Grande, Brazil, Vivienne Zhong Ying Su

Public Health Theses

Chikungunya is a mosquito-borne arboviral disease primarily transmitted by Aedes aegypti and Aedes albopictus that is rapidly emerging in new geographical settings because of climate change, viral adaptation, and globalization. Brazil has experienced the significant expansion of chikungunya over the past decade and has adopted novel vector control interventions, including Wolbachia-based population replacement, as part of its public health response. While the effectiveness of wMel Wolbachia on dengue incidence has been demonstrated across multiple settings, evidence on its effect on chikungunya risk remains limited. Large-scale releases of wMel-infected Aedes aegypti mosquitoes were implemented in the city of Campo Grande, Brazil …

Redefining Hospital-Acquired Rsv: Epidemiologic Burden And Probabilistic Classification In A Large Health System, Anna Trinh

Public Health Theses

Healthcare acquired respiratory syncytial virus (HA RSV) is an important but under recognized infection in adult patients. Current surveillance definitions classify RSV as healthcare acquired when a positive test occurs ≥48–72 hours after admission, despite a broad incubation period of 2–8 days which would allow community acquired infections to present several days into hospitalization. This thesis has two aims: (1) to describe the epidemiology of adult HA RSV cases in the Yale New Haven Health System (YNHHS) from 2021–2025, and (2) to develop an incubation period-based probabilistic model to assess the plausibility of each HA RSV classification. Among 2,905 laboratory-confirmed …