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Aggregating Twitter Text Through Generalized Linear Regression Models For Tweet Popularity Prediction And Automatic Topic Classification, Chen Mo, Jingjing Yin, Isaac Chun-Hai Fung, Zion Tse 2021 Georgia Southern University, Jiann-Ping Hsu College of Public Health

Aggregating Twitter Text Through Generalized Linear Regression Models For Tweet Popularity Prediction And Automatic Topic Classification, Chen Mo, Jingjing Yin, Isaac Chun-Hai Fung, Zion Tse

Biostatistics, Epidemiology & Environmental Health Sciences: Faculty Publications

Social media platforms have become accessible resources for health data analysis. However, the advanced computational techniques involved in big data text mining and analysis are challenging for public health data analysts to apply. This study proposes and explores the feasibility of a novel yet straightforward method by regressing the outcome of interest on the aggregated influence scores for association and/or classification analyses based on generalized linear models. The method reduces the document term matrix by transforming text data into a continuous summary score, thereby reducing the data dimension substantially and easing the data sparsity issue of the term matrix. To …


Characterizing Long Covid: Deep Phenotype Of A Complex Condition, Rachel R. Deer, Madeline A. Rock, Nicole Vasilevsky, Leigh Carmody, Halie Rando, Alfred J. Anzalone, Marc D. Basson, Tellen D. Bennett, Timothy Bergquist, Eilis A. Boudreau, Carolyn T. Bramante, James Brian Byrd, Tiffany J. Callahan, Lauren E. Chan, Haitao Chu, Christopher G. Chute, Ben D. Coleman, Hannah E. Davis, Joel Gagnier, Casey S. Greene, Ramakanth Kavuluru 2021 University of Texas Medical Branch

Characterizing Long Covid: Deep Phenotype Of A Complex Condition, Rachel R. Deer, Madeline A. Rock, Nicole Vasilevsky, Leigh Carmody, Halie Rando, Alfred J. Anzalone, Marc D. Basson, Tellen D. Bennett, Timothy Bergquist, Eilis A. Boudreau, Carolyn T. Bramante, James Brian Byrd, Tiffany J. Callahan, Lauren E. Chan, Haitao Chu, Christopher G. Chute, Ben D. Coleman, Hannah E. Davis, Joel Gagnier, Casey S. Greene, Ramakanth Kavuluru

Institute for Biomedical Informatics Faculty Publications

BACKGROUND: Numerous publications describe the clinical manifestations of post-acute sequelae of SARS-CoV-2 (PASC or "long COVID"), but they are difficult to integrate because of heterogeneous methods and the lack of a standard for denoting the many phenotypic manifestations. Patient-led studies are of particular importance for understanding the natural history of COVID-19, but integration is hampered because they often use different terms to describe the same symptom or condition. This significant disparity in patient versus clinical characterization motivated the proposed ontological approach to specifying manifestations, which will improve capture and integration of future long COVID studies.

METHODS: The Human Phenotype Ontology …


Causal Effects On Low Apgar At 5-Min And Stillbirth In A Malaria Maternal–Fetal Health Outcome Investigation: A Large Perinatal Surveillance Study In The Brazilian Amazon, Julio Abel Seijas-Chávez, Melissa Nolan Ph.D., MPH, Mary K. Lynn, Maria José Francalino da Rocha, Muana da Costa Araújo, Fernando Luiz Affonso Fonseca, Gabriel Zorello Laporta 2021 University of South Carolina

Causal Effects On Low Apgar At 5-Min And Stillbirth In A Malaria Maternal–Fetal Health Outcome Investigation: A Large Perinatal Surveillance Study In The Brazilian Amazon, Julio Abel Seijas-Chávez, Melissa Nolan Ph.D., Mph, Mary K. Lynn, Maria José Francalino Da Rocha, Muana Da Costa Araújo, Fernando Luiz Affonso Fonseca, Gabriel Zorello Laporta

Faculty Publications

Background

Malaria elimination in Brazil poses several challenges, including the control of Plasmodium falciparum foci and the hidden burden of Plasmodium vivax in pregnancy. Maternal malaria and fetal health outcomes were investigated with a perinatal surveillance study in the municipality of Cruzeiro do Sul, Acre state, Brazilian Amazon. The research questions are: what are the causal effects of low birth weight on low Apgar at 5-min and of perinatal anaemia on stillbirth?

Methods

From November 2018 to October 2019, pregnant women of ≥ 22 weeks or puerperal mothers, who delivered at the referral maternity hospital (Juruá Women and Children’s Hospital), …


The Dietary Inflammatory Index Is Not Associated With Gut Permeability Or Biomarkers Of Systemic Inflammation In Hiv Immunologic Non-Responders, Fat Malazogu, Rodney K. Rousseau, Nitin Shivappa MBBS, MPH, Ph.D., Sanja Huibner, Sharon L. Walmsley, Colin M. Kovacs, Erika Benko, Robert J. Reinhard, Ron Rosenes, James R. Hébert, Rupert Kaul 2021 University of South Carolina

The Dietary Inflammatory Index Is Not Associated With Gut Permeability Or Biomarkers Of Systemic Inflammation In Hiv Immunologic Non-Responders, Fat Malazogu, Rodney K. Rousseau, Nitin Shivappa Mbbs, Mph, Ph.D., Sanja Huibner, Sharon L. Walmsley, Colin M. Kovacs, Erika Benko, Robert J. Reinhard, Ron Rosenes, James R. Hébert, Rupert Kaul

Faculty Publications

Immunologic non-responders (INRs) are a subset of individuals living with HIV who have suboptimal blood CD4+ T cell recovery despite effective antiretroviral therapy (ART). They are at an increased risk of serious non-AIDS co-morbidities and death, and demonstrate enhanced systemic immune activation. In other populations diet has been correlated with markers of systemic inflammation through the Diet Inflammatory Index (DII), but this association has not been studied in persons living with HIV (PLWH). Blood was collected from 28 INR PLWH with a blood CD4+ T cell count <350/μL despite ≥2 years of effective ART. Participants completed a Canadian Diet History Questionnaire, and their responses were used to calculate the DII. Plasma inflammatory markers (IFNγ, TNF, IL-6, sVCAM, D-dimer, sCD14 and CRP) were assayed by ELISA, cellular immune activation (HLA-DR and CD38 on CD4+ and CD8+ T cells) was quantified using flow cytometry, and small bowel permeability assessed by calculation of the urine LacMan ratio after drinking a mix of lactulose and mannitol. Participants were a median age of 57 years, had been on effective ART for 15 years, and the median DII was −1.91 (range of −3.78 to +2.23). No correlation was observed between DII and plasma markers of inflammation, levels of T cell activation, gut permeability, or the biomarker of bacterial translocation sCD14. Self-reported alcohol intake, a potential confounder of the relationship between diet and inflammatory biomarkers, was also not associated with systemic inflammation or gut permeability. Our findings suggest that other mechanisms, rather than diet, are likely to be the major driver of systemic inflammation in INR individuals.


Association Between Diet Quality Indices And Incidence Of Type 2 Diabetes In The Melbourne Collaborative Cohort Study, Allison M. Hodge, Md Nazmul Karim, James Hébert ScD, Nitin Shivappa MBBS, MPH, Ph.D., Barbora de Courten 2021 University of South Carolina

Association Between Diet Quality Indices And Incidence Of Type 2 Diabetes In The Melbourne Collaborative Cohort Study, Allison M. Hodge, Md Nazmul Karim, James Hébert Scd, Nitin Shivappa Mbbs, Mph, Ph.D., Barbora De Courten

Faculty Publications

Type 2 diabetes mellitus is a common condition whose incidence is increasing worldwide, and for which obesity and diet are important risk factors. The aim of this study was to assess the association of three diet quality scores with diabetes risk and how much of the association was mediated through body size. The Melbourne Collaborative Cohort Study recruited 41,513 men and women aged 40–69 years during 1990–1994. At baseline, data were collected on lifestyle and diet, anthropometric measures were performed. Incident diabetes was assessed by self-report at follow-up surveys in 1994–1998 and 2003–2007. The associations between the dietary inflammatory index …


A 6-Cpg Validated Methylation Risk Score Model For Metabolic Syndrome: The Hypergen And Goldn Studies, Bertha A. Hidalgo, Bre Minniefield, Amit Patki, Rikki Tanner, Minoo Bagheri, Hemant K. Tiwari, Donna K. Arnett, Marguerite Ryan Irvin 2021 University of Alabama at Birmingham

A 6-Cpg Validated Methylation Risk Score Model For Metabolic Syndrome: The Hypergen And Goldn Studies, Bertha A. Hidalgo, Bre Minniefield, Amit Patki, Rikki Tanner, Minoo Bagheri, Hemant K. Tiwari, Donna K. Arnett, Marguerite Ryan Irvin

Epidemiology and Environmental Health Faculty Publications

There has been great interest in genetic risk prediction using risk scores in recent years, however, the utility of scores developed in European populations and later applied to non-European populations has not been successful. The goal of this study was to create a methylation risk score (MRS) for metabolic syndrome (MetS), demonstrating the utility of MRS across race groups using cross-sectional data from the Hypertension Genetic Epidemiology Network (HyperGEN, N = 614 African Americans (AA)) and the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN, N = 995 European Americans (EA)). To demonstrate this, we first selected cytosine-guanine dinucleotides …


Association Between Neighborhood Social Deprivation And Stage At Diagnosis Among Breast Cancer Patients In South Carolina, Oluwole Adeyemi Babatunde, Whitney Zahnd Ph.D., Jan Eberth Ph.D., Andrew B. Lawson, Swann Arp Adams, Eric Adjei Boakye, Melanie S. Jefferson, Caitlin G. Allen, John L. Pearce, Hong Li, Chanita Hughes Halbert 2021 University of South Carolina

Association Between Neighborhood Social Deprivation And Stage At Diagnosis Among Breast Cancer Patients In South Carolina, Oluwole Adeyemi Babatunde, Whitney Zahnd Ph.D., Jan Eberth Ph.D., Andrew B. Lawson, Swann Arp Adams, Eric Adjei Boakye, Melanie S. Jefferson, Caitlin G. Allen, John L. Pearce, Hong Li, Chanita Hughes Halbert

Faculty Publications

The purpose of this study was to examine the association between neighborhood social deprivation and individual-level characteristics on breast cancer staging in African American and white breast cancer patients. We established a retrospective cohort of patients with breast cancer diagnosed from 1996 to 2015 using the South Carolina Central Cancer Registry. We abstracted sociodemographic and clinical variables from the registry and linked these data to a county-level composite that captured neighborhood social conditions—the social deprivation index (SDI). Data were analyzed using chi-square tests, Student’s t-test, and multivariable ordinal regression analysis to evaluate associations. The study sample included 52,803 female patients …


Genomics Of Postprandial Lipidomics In The Genetics Of Lipid-Lowering Drugs And Diet Network Study, Marguerite R. Irvin, May E. Montasser, Tobias Kind, Sili Fan, Dinesh K. Barupal, Amit Patki, Rikki M. Tanner, Nicole D. Armstrong, Kathleen A. Ryan, Steven A. Claas, Jeffrey R. O’Connell, Hemant K. Tiwari, Donna K. Arnett 2021 University of Alabama at Birmingham

Genomics Of Postprandial Lipidomics In The Genetics Of Lipid-Lowering Drugs And Diet Network Study, Marguerite R. Irvin, May E. Montasser, Tobias Kind, Sili Fan, Dinesh K. Barupal, Amit Patki, Rikki M. Tanner, Nicole D. Armstrong, Kathleen A. Ryan, Steven A. Claas, Jeffrey R. O’Connell, Hemant K. Tiwari, Donna K. Arnett

Epidemiology and Environmental Health Faculty Publications

Postprandial lipemia (PPL) is an important risk factor for cardiovascular disease. Inter-individual variation in the dietary response to a meal is known to be influenced by genetic factors, yet genes that dictate variation in postprandial lipids are not completely characterized. Genetic studies of the plasma lipidome can help to better understand postprandial metabolism by isolating lipid molecular species which are more closely related to the genome. We measured the plasma lipidome at fasting and 6 h after a standardized high-fat meal in 668 participants from the Genetics of Lipid-Lowering Drugs and Diet Network study (GOLDN) using ultra-performance liquid chromatography coupled …


Verrucous Carcinoma Of The Vulva: Patterns Of Care And Treatment Outcomes., Sara M. Dryden, Leonid B. Reshko, Jeremy T. Gaskins, Scott R. Silva 2021 University of Louisville

Verrucous Carcinoma Of The Vulva: Patterns Of Care And Treatment Outcomes., Sara M. Dryden, Leonid B. Reshko, Jeremy T. Gaskins, Scott R. Silva

Faculty and Staff Scholarship

Background: Verrucous vulvar carcinoma (VC) is an uncommon and distinct histologic subtype of squamous cell carcinoma (SCC). The available literature on VC is currently limited to case reports and small single institution studies. Aims: The goals of this study were to analyze data from the National Cancer Database (NCDB) to quantitate the incidence of VC and to investigate the effects of patient demographics, tumor characteristics, and treatment regimens on overall survival (OS) in women with verrucous vulvar carcinoma. Methods and results: Patients diagnosed with vulvar SCC or VC between the years of 2004 and 2016 were identified in the NCDB. …


Differential Privacy For Regression Modeling In Health: An Evaluation Of Algorithms, Joseph Ficek 2021 University of South Florida

Differential Privacy For Regression Modeling In Health: An Evaluation Of Algorithms, Joseph Ficek

USF Tampa Graduate Theses and Dissertations

Background: There is a need for rigorous and standardized methods of privacy protection for shared data in the health sciences. Differential privacy is one such method that has gained much popularity due to its versatility and robustness. This study evaluates differential privacy for explanatory regression modeling in the context of health research.

Methods: Surveyed and newly proposed algorithms were evaluated with respect to the accuracy (bias and RMSE) of coefficient estimates, the empirical coverage probability of confidence intervals, and the power and type I error rates of hypothesis tests. Evaluations took place in both simulated and real data from a …


Effects Of Sesame Consumption On Inflammatory Biomarkers In Humans: A Systematic Review And Meta-Analysis Of Randomized Controlled Trials, Shabnam Rafiee, Roghaye Faryabi, Mohammad Ali Zareian, Jessie Hawkins, Nitin Shivappa MBBS, MPH, Ph.D., Laila Shirbeigi 2021 University of South Carolina

Effects Of Sesame Consumption On Inflammatory Biomarkers In Humans: A Systematic Review And Meta-Analysis Of Randomized Controlled Trials, Shabnam Rafiee, Roghaye Faryabi, Mohammad Ali Zareian, Jessie Hawkins, Nitin Shivappa Mbbs, Mph, Ph.D., Laila Shirbeigi

Faculty Publications

Objectives. Existing evidence produces conflicting findings regarding the effect of sesame intake on inflammatory biomarkers; thisknowledge gap has yet to be met through systematic review and meta-analysis. )is meta-analysis of randomized, controlledclinical trials (RCTs) was conducted to evaluate the effects of sesame consumption on markers of inflammation in humans. Methods. PubMed, Scopus, and the Cochrane Database of Systematic Reviews were searched through August 2020 to identify relevant papers for inclusion. Using the random-effects model, data were evaluated as weighted mean differences (WMD) with 95% confidence intervals (CI). Cochrane’s Q and I-squared (I2) tests were used to …


A Comparison Of Bayesian Spatial Models For Hiv Mapping In South Africa, Kassahun Abere Ayalew, Samuel Manda, Bo Cai Ph.D. 2021 University of South Carolina - Columbia

A Comparison Of Bayesian Spatial Models For Hiv Mapping In South Africa, Kassahun Abere Ayalew, Samuel Manda, Bo Cai Ph.D.

Faculty Publications

Despite making significant progress in tackling its HIV epidemic, South Africa, with 7.7 million people living with HIV, still has the biggest HIV epidemic in the world. The Government, in collaboration with developmental partners and agencies, has been strengthening its responses to the HIV epidemic to better target the delivery of HIV care, treatment strategies and prevention services. Population-based household HIV surveys have, over time, contributed to the country’s efforts in monitoring and understanding the magnitude and heterogeneity of the HIV epidemic. Local-level monitoring of progress made against HIV and AIDS is increasingly needed for decision making. Previous studies have …


Determining Diagnosis Date Of Diabetes Using Structured Electronic Health Record (Ehr) Data: The Search For Diabetes In Youth Study, Kristin M. Lenoir, Lynne E. Wagenknecht, Jasmin Divers, Ramon Casanova, Dana Dabelea, Sharon Saydah, Catherine Pihoker, Angela D. Liese Ph.D., Debra Standiford, Richard Hamman, Brian J. Wells, the SEARCH for Diabetes in Youth Study Group 2021 University of South Carolina

Determining Diagnosis Date Of Diabetes Using Structured Electronic Health Record (Ehr) Data: The Search For Diabetes In Youth Study, Kristin M. Lenoir, Lynne E. Wagenknecht, Jasmin Divers, Ramon Casanova, Dana Dabelea, Sharon Saydah, Catherine Pihoker, Angela D. Liese Ph.D., Debra Standiford, Richard Hamman, Brian J. Wells, The Search For Diabetes In Youth Study Group

Faculty Publications

Background Disease surveillance of diabetes among youth has relied mainly upon manual chart review. However, increasingly available structured electronic health record (EHR) data have been shown to yield accurate determinations of diabetes status and type. Validated algorithms to determine date of diabetes diagnosis are lacking. The objective of this work is to validate two EHR-based algorithms to determine date of diagnosis of diabetes. Methods A rule-based ICD-10 algorithm identified youth with diabetes from structured EHR data over the period of 2009 through 2017 within three children’s hospitals that participate in the SEARCH for Diabetes in Youth Study: Cincinnati Children’s Hospital, …


Ovarian Cancer Epidemiology, Healthcare Access And Disparities (Orchid): Methodology For A Population-Based Study Of Black, Hispanic And White Patients With Ovarian Cancer, Tomi Akinyemiju, April Deveaux, Lauren Wilson, Anjali Gupta, Ashwini Joshi, Malcolm Bevel, Chioma Omeogu, Onyinye Ohamadike, Bin Huang, Maria Pisu, Margaret Liang, Molly McFatrich, Erin Daniell, Laura Jane Fish, Kevin Ward, Maria Schymura, Andrew Berchuck, Arnold L. Potosky 2021 Duke University

Ovarian Cancer Epidemiology, Healthcare Access And Disparities (Orchid): Methodology For A Population-Based Study Of Black, Hispanic And White Patients With Ovarian Cancer, Tomi Akinyemiju, April Deveaux, Lauren Wilson, Anjali Gupta, Ashwini Joshi, Malcolm Bevel, Chioma Omeogu, Onyinye Ohamadike, Bin Huang, Maria Pisu, Margaret Liang, Molly Mcfatrich, Erin Daniell, Laura Jane Fish, Kevin Ward, Maria Schymura, Andrew Berchuck, Arnold L. Potosky

Biostatistics Faculty Publications

INTRODUCTION: Less than 40% of patients with ovarian cancer (OC) in the USA receive stage-appropriate guideline-adherent surgery and chemotherapy. Black patients with cancer report greater depression, pain and fatigue than white patients. Lack of access to healthcare likely contributes to low treatment rates and racial differences in outcomes. The Ovarian Cancer Epidemiology, Healthcare Access and Disparities study aims to characterise healthcare access (HCA) across five specific dimensions-Availability, Affordability, Accessibility, Accommodation and Acceptability-among black, Hispanic and white patients with OC, evaluate the impact of HCA on quality of treatment, supportive care and survival, and explore biological mechanisms that may contribute to …


The Mediating/Moderating Role Of Cultural Context Factors On Self-Care Practices Among Those Living With Diabetes In Rural Appalachia, Brittany L. Smalls, Adebola Adegboyega, Ellen Combs, Matthew Rutledge, Philip M. Westgate, Md. Tofial Azam, Felipe De La Barra, Lovoria B. Williams, Nancy E. Schoenberg 2021 University of Kentucky

The Mediating/Moderating Role Of Cultural Context Factors On Self-Care Practices Among Those Living With Diabetes In Rural Appalachia, Brittany L. Smalls, Adebola Adegboyega, Ellen Combs, Matthew Rutledge, Philip M. Westgate, Md. Tofial Azam, Felipe De La Barra, Lovoria B. Williams, Nancy E. Schoenberg

Family and Community Medicine Faculty Publications

Background

The aim of this study was to examine whether cultural factors, such as religiosity and social support, mediate/moderate the relationship between personal/psychosocial factors and T2DM self-care in a rural Appalachian community.

Methods

Regression models were utilized to assess for mediation and moderation. Multilevel linear mixed effects models and GEE-type logistic regression models were fit for continuous (social support, self-care) and binary (religiosity) outcomes, respectively.

Results

The results indicated that cultural context factors (religiosity and social support) can mediate/moderate the relationship between psychosocial factors and T2DM self-care. Specifically, after adjusting for demographic variables, the findings suggested that social support may …


An Evaluation Of The Organic Carbon Content Found In Fucus Vesiculosus And Ascophyllum Nodosum From Skutulsfjörður And Eyjafjörður, Iceland, Sylvie Alexander 2021 SIT Study Abroad

An Evaluation Of The Organic Carbon Content Found In Fucus Vesiculosus And Ascophyllum Nodosum From Skutulsfjörður And Eyjafjörður, Iceland, Sylvie Alexander

Independent Study Project (ISP) Collection

In response to global warming and changing climate, carbon sequestration through macroalgal cultivation has emerged as a possible climate change mitigation technique. Macroalgal cultivation’s relationship to carbon sequestration however is still not well understood. It is imperative to understand macroalgae’s connection to carbon sequestration to evaluate if macroalgal cultivation can help combat climate change. There is a gap in literature regarding the carbon content of Icelandic macroalgae and therefore the contribution of Icelandic macroalgae to national and global carbon sequestration estimates. This paper aims to address this knowledge gap by evaluating organic carbon content of Fucus vesiculosus and Ascophyllum nodosum …


Bayesian Calibration Of The Icrp Zirconium Biokinetic Model And Use Of Canned Priors For The Evaluation Of Bioassay, Thomas Raymond LaBone 2021 University of South Carolina

Bayesian Calibration Of The Icrp Zirconium Biokinetic Model And Use Of Canned Priors For The Evaluation Of Bioassay, Thomas Raymond Labone

Theses and Dissertations

The International Commission on Radiological Protection (ICRP) publishes biokinetic models that relate measurements of radioactive material in the body and excreta (bioassay) to the amount of the material taken into the body (intake). Given the intake and the biokinetic model, radiation dose to organs and tissues can be calculated. The ICRP approximates the biokinetics of radioactive materials in the body with compartmental models expressed mathematically as a system of ordinary differential equations, for which they provide point estimates of the rate constants. Inaccurate estimates of intake and radiation dose can result in cases where the biokinetics of an individual differ …


Correcting For Measurement Error In The Outcome When Estimating The Distribution Of Time To Pregnancy With The Current Duration Approach, Nicole Nasrallah 2021 University of South Carolina

Correcting For Measurement Error In The Outcome When Estimating The Distribution Of Time To Pregnancy With The Current Duration Approach, Nicole Nasrallah

Theses and Dissertations

The current duration approach to modeling time-to-pregnancy (TTP) models the length of pregnancy attempt for women that are currently attempting pregnancy. There is a scarcity of studies, let alone TTP studies, that account for measurement error in the outcome. Previously, the benefits of a piecewise constant model with regards to bias in estimates of the survival function with measurement error and the parametric modelling of TTP was shown. In this thesis, correcting for measurement error in the outcome with the current duration approach is explored through piecewise constant models with log-normal measurement error. Five different methods are compared to determine …


Multiple Frailty Model For Spatially Correlated Interval-Censored, Wanfang Zhang 2021 University of South Carolina

Multiple Frailty Model For Spatially Correlated Interval-Censored, Wanfang Zhang

Theses and Dissertations

In this paper, we consider the problem of multiple frailty selection for general interval-censored spatial survival data, which often occurs in clinical trials and epidemiological studies. The general interval-censored data is a mixture of left-, right- and interval-censored data. We propose a Bayesian semiparametric approach based on the Cox proportional hazard model, where monotone splines were used for non-parametrical modeling of the cumulative baseline hazards where the variable selection priors were used for frailty selection. A two-stage data augmentation with Poisson latent variables is developed for efficient computation. The approach is evaluated based a simulation study and illustrated using a …


Marginally Interpretable Models And Multilevel Models For Quantile Regression With Random-Effects, Nahid Sultana Sumi 2021 University of South Carolina

Marginally Interpretable Models And Multilevel Models For Quantile Regression With Random-Effects, Nahid Sultana Sumi

Theses and Dissertations

The quantile regression model is an active area of statistical research that has received a lot of attention. This complements the most widely used statistical tool, that is, mean regression analysis. Quantile regression analysis It has become more flexible because of its properties that include no assumption on the distribution of the response variable, equivalent to monotone transformations, and robustness to outliers. However, regression analysis offers methodological challenges if the observations are not independent. Cluster, multilevel, and repeated measures (longitudinal data) designs introduce such dependence. The correlation between observations on the same units or clusters should be accounted for to …


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