Epidemiology Commons^™

The Role Of Mathematical Modeling In Designing And Evaluating Antimicrobial Stewardship Programs, Lester Caudill, Joanna R. Wares

Department of Math & Statistics Faculty Publications

Antimicrobial agent effectiveness continues to be threatened by the rise and spread of pathogen strains that exhibit drug resistance. This challenge is most acute in healthcare facilities where the well-established connection between resistance and sub-optimal antimicrobial use has prompted the creation of antimicrobial stewardship programs (ASPs). Mathematical models offer tremendous potential for serving as an alternative to controlled human experimentation for assessing the effectiveness of ASPs. Models can simulate controlled randomized experiments between groups of virtual patients, some treated with the ASP measure under investigation, and some without. By removing the limitations inherent in human experimentation, including health risks, study …

Sex Disparities In Access To Acute Stroke Care: Can Telemedicine Mitigate This Effect?, Catherine Wolff, Amelia K. Boehme, Karen Albright, Tzu-Ching Wu, Michael Mullen, Sean Savitz, Charles Branas, James Grotta, Brendan Carr

Journal of Health Disparities Research and Practice

Background: Women have more frequent and severe ischemic strokes than men, and are less likely to receive treatment for acute stroke. Primary stroke centers (PSCs) have been shown to utilize treatment more frequently. Further, as telemedicine (TM) has expanded access to acute stroke care we sought to investigate the association between PSC, TM and access to acute stroke care in the state of Texas.

Methods: Texas hospitals and resources were identified from the 2009 American Hospital Association Annual Survey. Hospitals were categorized as: (1) stand-alone PSCs not using telemedicine for acute stroke care, (2) PSCs using telemedicine for acute stroke …

Incidence, Persistence, And Recurrence Of Anogenital Α- Mucosal Hpv Infections (Hpv 6, 11, 16, 18, 31, 33, 45, 52 And 58), Shitaldas J. Pamnani

USF Tampa Graduate Theses and Dissertations

Objectives: The aims of this study were to: 1) Assess whether naturally induced anti-HPV antibodies are associated with subsequent acquisition of genital HPV 6, 11, 16, and 18 infections in men, 2) assess the recurrence (redetection) of genital HPV infections of the 9-valent vaccine HPV types and investigate factors associated with recurrent infections among men, and 3) assess the risk of type-specific sequential acquisition of anal HPV infection following a genital HPV infection of the 9-valent vaccine HPV types among men who have sex with women (MSW).

Methods: 4,123 healthy men were followed every six months (median follow-up time 4.1 …

Incidence And Risk Factors Of Thromboembolism With Multiple Myeloma In The Presence Of Death As A Competing Risk: An Empirical Comparison Of Statistical Methodologies, Joshua D. Brown, Val R. Adams

Pharmacy Practice and Science Faculty Publications

Multiple myeloma (MM) has an inherent high risk of thromboembolic events associated with patient as well as disease- and treatment-related factors. Previous studies have assessed the association of MM-related thromboembolism using “traditional” Kaplan–Meier (KM) and/or Cox proportional hazard (PH) regression. In the presence of high incidence of death, as would be the case in cancer patients with advanced age, these statistical models will produce bias estimates. Instead, a competing risk framework should be used. This study assessed the baseline patient demographic and clinical characteristics associated with MM-related thromboembolism and compared the cumulative incidence and the measures of association obtained using …

Alzheimer's Biomarkers Are Correlated With Brain Connectivity In Older Adults Differentially During Resting And Task States, Yang Jiang, Haiqing Huang, Erin Abner, Lucas S. Broster, Gregory A. Jicha, Frederick A. Schmitt, Richard Kryscio, Anders H. Andersen, David Powell, Linda J. Van Eldik, Brian T. Gold, Peter T. Nelson, Charles D. Smith, Mingzhou Ding

Behavioral Science Faculty Publications

β-amyloid (Aβ) plaques and tau-related neurodegeneration are pathologic hallmarks of Alzheimer’s disease (AD). The utility of AD biomarkers, including those measured in cerebrospinal fluid (CSF), in predicting future AD risk and cognitive decline is still being refined. Here, we explored potential relationships between functional connectivity (FC) patterns within the default-mode network (DMN), age, CSF biomarkers (Aβ₄₂ and pTau₁₈₁), and cognitive status in older adults. Multiple measures of FC were explored, including a novel time series-based measure [total interdependence (TI)]. In our sample of 27 cognitively normal older adults, no significant associations were found between levels of Aβ …

High-Altitude Pulmonary Hypertension: An Update On Disease Pathogenesis And Management, Aibek E. Mirrakhimov, Kingman P. Strohl

Internal Medicine Faculty Publications

High-altitude pulmonary hypertension (HAPH) affects individuals residing at altitudes of 2,500 meters and higher. Numerous pathogenic variables play a role in disease inception and progression and include low oxygen concentration in inspired air, vasculopathy, and metabolic abnormalities. Since HAPH affects only some people living at high altitude genetic factors play a significant role in its pathogenesis.

The clinical presentation of HAPH is nonspecific and includes fatigue, shortness of breath, cognitive deficits, cough, and in advanced cases hepatosplenomegaly and overt right-sided heart failure. A thorough history is important and should include a search for additional risk factors for lung disease and …

Multilevel Analysis Of Individual, Neighborhood, And Health Care Facility Characteristics Associated With Achievement And Maintenance Of Hiv Viral Suppression Among Persons Newly Diagnosed With Hiv In New York City, Ellen W. Wiewel

Dissertations, Theses, and Capstone Projects

Objective

To investigate the effect of individual, health care facility, and neighborhood characteristics on achievement and maintenance of HIV viral suppression, among New York City residents aged 13 years and older diagnosed with HIV between 2006 and 2012.

Methods

I used individual-level data from the New York City HIV surveillance registry and Case Surveillance-Based Sampling, facility-level data from the surveillance registry, and neighborhood-level data from the U.S. Census and American Community Survey. The outcomes of interest were first viral suppression after diagnosis (Aims 1 and 3; ≤400 copies/mL) and virologic failure after first suppression among persons who achieved suppression (Aim …

Models For Hsv Shedding Must Account For Two Levels Of Overdispersion, Amalia Magaret

UW Biostatistics Working Paper Series

We have frequently implemented crossover studies to evaluate new therapeutic interventions for genital herpes simplex virus infection. The outcome measured to assess the efficacy of interventions on herpes disease severity is the viral shedding rate, defined as the frequency of detection of HSV on the genital skin and mucosa. We performed a simulation study to ascertain whether our standard model, which we have used previously, was appropriately considering all the necessary features of the shedding data to provide correct inference. We simulated shedding data under our standard, validated assumptions and assessed the ability of 5 different models to reproduce the …

Significance Of Epicardial And Intrathoracic Adipose Tissue Volume Among Type 1 Diabetes Patients In The Dcct/Edic: A Pilot Study., Sirous Darabian, Jye-Yu C Backlund, Patricia A Cleary, Nasim Sheidaee, Ionut Bebu, John M. Lachin, Matthew J Budoff, Dcct/Edic Research Group

GW Biostatistics Center

Introduction

Type 1 diabetes (T1DM) patients are at increased risk of coronary artery disease (CAD). This pilot study sought to evaluate the relationship between epicardial adipose tissue (EAT) and intra-thoracic adipose tissue (IAT) volumes and cardio-metabolic risk factors in T1DM.

Method

EAT/IAT volumes in 100 patients, underwent non-contrast cardiac computed tomography in the Diabetes Control and Complications Trial /Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study were measured by a certified reader. Fat was defined as pixels’ density of -30 to -190 Hounsfield Unit. The associations were assessed using–Pearson partial correlation and linear regression models adjusted for gender and age …

Importance Of Hereditary And Selected Environmental Risk Factors In The Etiology Of Inflammatory Breast Cancer: A Case-Comparison Study., Roxana Moslehi, Elizabeth Freedman, Nur Zeinomar, Carmela Veneroso, Paul H. Levine

Epidemiology Faculty Publications

BACKGROUND: To assess the importance of heredity in the etiology of inflammatory breast cancer (IBC), we compared IBC patients to several carefully chosen comparison groups with respect to the prevalence of first-degree family history of breast cancer.

METHODS: IBC cases (n = 141) were compared to non-inflammatory breast cancer cases (n = 178) ascertained through George Washington University (GWU) with respect to the prevalence of first-degree family history of breast cancer and selected environmental/lifestyle risk factors for breast cancer. Similar comparisons were conducted with subjects from three case-control studies: breast cancer cases (n = 1145) and unaffected controls (n = …

Investigating The Efficacy Of Vocal Function Exercises In Improving Vocal Function In Adults Irradiated For Laryngeal Cancers: A Three Part Dissertation, Vrushali Angadi

Theses and Dissertations--Rehabilitation Sciences

Deterioration in voice quality following radiation therapy for the treatment of laryngeal cancers (LC) is well documented in literature. The majority of studies show that these voice problems are long term and in some cases permanent. Deterioration in voice quality, especially over a period of time could lead to significant communication difficulties in daily life or in some cases could even result in loss of profession. Despite the negative effects of radiation therapy on voice quality being well documented, few studies have focused on the efficacy of voice therapy in the irradiated LC population.

The purpose of this study was …

Epidemiology Of Pediatric Prehospital Basic Life Support Care In The United States, Leigh Ann Diggs, Manasi Sheth-Chandra, Gianluca De Leo

Community & Environmental Health Faculty Publications

Children have unique medical needs compared to adults. Emergency medical services personnel need proper equipment and training to care for children. The purpose of this study is to characterize emergency medical services pediatric basic life support to help better understand the needs of children transported by ambulance. Pediatric basic life support patients were identified in this retrospective descriptive study. Descriptive statistics were used to examine incident location, possible injury, cardiac arrest, resuscitation attempted, chief complaint, primary symptom, provider's primary impression, cause of injury, and procedures performed during pediatric basic life support calls using the largest aggregate of emergency medical services …

The Association Of Cancer Development In Patients With Systemic Lupus Erythematosus, Rose Michelle Coley

Walden Dissertations and Doctoral Studies

The Association of Cancer Development in Patients with Systemic Lupus Erythematosus by

Rose Michelle Coley

MPH, Walden University, 2011

BS, University of Mount Olive, 2008

Dissertation Submitted in Partial Fulfillment

of the Requirements for the Degree of

Doctor of Philosophy

Public Health

Walden University

March 2016

Both cancer and autoimmune diseases have been associated with numerous factors that may independently lead to the development of either disease. When these factors overlap the difficulty in assessing association is compounded. The numerous factors that are thought to cause systemic lupus erythematosus (SLE), which leads to the development of cancer, makes the study …

Comparison Of Neovascular Age-Related Macular Degeneration Populations In The United States, Susan Lynette Coultas

Walden Dissertations and Doctoral Studies

Age-related macular degeneration (AMD) is one of the leading causes of blindness in the United States in people who are 50 and older. The safety and efficacy of aflibercept for the treatment of late stage neovascular AMD (NAMD) has been demonstrated by clinical trials among several populations; however, it is unclear whether all NAMD patients respond in the same manner as was studied in the clinical trials. The purpose of this study was to examine if populations of patients treated with aflibercept for the treatment of NAMD were significantly different from one another in terms of health characteristics, treatment regimens, …

Incidence And Factors Associated With Nonalcoholic Fatty Liver Disease Among Patients With Rheumatoid Arthritis, Ani K. John

Walden Dissertations and Doctoral Studies

Nonalcoholic fatty liver disease (NAFLD) has become one of the most common hepatic diseases worldwide, making the diagnosis and management of NAFLD an emerging public health issue. Theories associated with NAFLD surmise that inflammation may be the root cause, along with the complex interplay of other chronic conditions such as obesity, metabolic syndrome, diabetes, dyslipidemia, and cardiovascular disease (CVD). It is unknown if other inflammatory conditions such as rheumatoid arthritis (RA), along with the use of methotrexate (MTX), might confer increased risk for NAFLD. Longitudinal data collected from a retrospective cohort of 17,481 adult RA patients in the United States …

Prenatal Exposure To Perfluoroalkyl Acids And Serum Testosterone Concentrations At 15 Years Of Age In Female Alspac Study Participants, Mildred Maisonet, Antonia M. Calafat, Michele Marcus, Jouni J.K. Jaakkola, Hany Lashen

ETSU Faculty Works

Background: Exposure to perfluorooctane sulfonic acid (PFOS) or to perfluorooctanoic acid (PFOA) increases mouse and human peroxisome proliferator–activated receptor alpha (PPARα) subtype activity, which influences lipid metabolism. Because cholesterol is the substrate from which testosterone is synthesized, exposure to these substances has the potential to alter testosterone concentrations.

Objectives: We explored associations of total testosterone and sex hormone–binding globulin (SHBG) concentrations at age 15 years with prenatal exposures to PFOS, PFOA, perfluorohexane sulfonic acid (PFHxS), and perfluoronanoic acid (PFNA) in females.

Methods: Prenatal concentrations of the perfluoroalkyl acids (PFAAs) were measured in serum collected from pregnant mothers at enrollment (1991–1992) …

Microrna Molecular Profiling From Matched Tumor And Bio-Fluids In Bladder Cancer, David A. Armstrong, Benjamin B. Green, John D. Seigne, Alan R. Schned, Carmen Marsit

Dartmouth Scholarship

MicroRNAs have been identified as potential cancer biomarkers due to their presence and stability in many body fluids including urine and plasma, but the relationship of the pattern of expression of these messengers across various biological media has not been addressed and could provide important information in order to translate these biomarkers for epidemiologic or clinical use. We analyzed microRNA of matched FFPE-tumor tissue, plasma, urine exosomes (n = 16) and WBCs (n = 11) from patients with bladder cancer, using Nanostring miRNA assays and droplet digital PCR for validation. Pearson correlations were used to compare expression between …

Nested Partially-Latent, Class Models For Dependent Binary Data, Estimating Disease Etiology, Zhenke Wu, Maria Deloria-Knoll, Scott L. Zeger

Johns Hopkins University, Dept. of Biostatistics Working Papers

The Pneumonia Etiology Research for Child Health (PERCH) study seeks to use modern measurement technology to infer the causes of pneumonia for which gold-standard evidence is unavailable. The paper describes a latent variable model designed to infer from case-control data the etiology distribution for the population of cases, and for an individual case given his or her measurements. We assume each observation is drawn from a mixture model for which each component represents one cause or disease class. The model addresses a major limitation of the traditional latent class approach by taking account of residual dependence among multivariate binary outcome …

Dynapenic Obesity And The Effect On Long-Term Physical Function And Quality Of Life: Data From The Osteoarthritis Initiative, John A. Batsis, Alicia J. Zbehlik, Dawna Pidgeon, Stephen J. Bartels

Dartmouth Scholarship

Obesity is associated with functional impairment, institutionalization, and increased mortality risk in elders. Dynapenia is defined as reduced muscle strength and is a known independent predictor of adverse events and disability. The synergy between dynapenia and obesity leads to worse outcomes than either independently. We identified the impact of dynapenic obesity in a cohort at risk for and with knee osteoarthritis on function.

Association Of Obesity With Infertility Among Pakistani Men: A Case Control Study, Nida Zahid, Sarah Saleem, Syed Iqbal Azam, Tariq Moatter

Community Health Sciences

Background: The reported prevalence of infertility in Pakistan is 21% of which 35% is contributed by male factor. Male infertility has multifactorial etiologies ranging from modifiable to genetic risk factors. Among all the risk factors that may account for male infertility, obesity is one of the emerging public health problems. Therefore, the aim of the study was to determine the association of obesity with infertility in Pakistani men.
Methods: We conducted a case control study. Cases were men with impaired semen parameters and controls did not have impaired semen parameters.
Results: The final multivariable logistic regression model after adjusting for …

Caffeine Consumption Contributes To Skin Intrinsic Fluorescence In Type 1 Diabetes., Karen M Eny, Trevor J Orchard, Rachel Grace Miller, John Maynard, Denis M Grant, Tina Costacou, Patricia A. Cleary, Barbara H Braffett, Andrew D Paterson, Dcct/Edic Research Group

GW Biostatistics Center

Background: A variant (rs1495741) in the gene for the N-acetyltransferase 2 (NAT2) protein is associated with skin intrinsic fluorescence (SIF), a noninvasive measure of advanced glycation end products and other fluorophores in the skin. Because NAT2 is involved in caffeine metabolism, we aimed to determine whether caffeine consumption is associated with SIF and whether rs1495741 is associated with SIF independently of caffeine.

Materials and Methods: SIF was measured in 1,181 participants with type 1 diabetes from the Epidemiology of Diabetes Interventions and Complications study. Two measures of SIF were used: SIF1, using a 375-nm excitation light-emitting diode (LED), and …

Nitrate And Nitrite Ingestion And Risk Of Ovarian Cancer Among Postmenopausal Women In Iowa, Maki Inoue-Choi, Rena R. Jones, Kristin E. Anderson, Kenneth P. Cantor, James R. Cerhan, Stuart Krasner, Kimberly Robien, Peter J. Weyer, Mary H. Ward

Epidemiology Faculty Publications

Nitrate and nitrite are precursors in the endogenous formation of N-nitroso compounds (NOC), potential human carcinogens. We evaluated the association of nitrate and nitrite ingestion with postmenopausal ovarian cancer risk in the Iowa Women's Health Study. Among 28,555 postmenopausal women, we identified 315 incident epithelial ovarian cancers from 1986 to 2010. Dietary nitrate and nitrite intakes were assessed at baseline using food frequency questionnaire data. Drinking water source at home was obtained in a 1989 follow-up survey. Nitrate-nitrogen (NO₃-N) and total trihalomethane (TTHM) levels for Iowa public water utilities were linked to residences and average levels were …

Cost-Effectiveness Of Coronary Artery Calcium Testing For Coronary Heart And Cardiovascular Disease Risk Prediction To Guide Statin Allocation: The Multi-Ethnic Study Of Atherosclerosis (Mesa), Khurram Nasir

All Publications

BACKGROUND: The Multi-Ethnic Study of Atherosclerosis (MESA) showed that the addition of coronary artery calcium (CAC) to traditional risk factors improves risk classification, particularly in intermediate risk asymptomatic patients with LDL cholesterol levels /dL. However, the cost-effectiveness of incorporating CAC into treatment decision rules has yet to be clearly delineated.OBJECTIVE: To model the cost-effectiveness of CAC for cardiovascular risk stratification in asymptomatic, intermediate risk patients not taking a statin. Treatment based on CAC was compared to (1) treatment of all intermediate-risk patients, and (2) treatment on the basis of United States guidelines.METHODS: We developed a Markov model of first coronary …

Obesity And Metabolic Phenotypes (Metabolically Healthy And Unhealthy Variants) Are Significantly Associated With Prevalence Of Elevated C-Reactive Protein And Hepatic Steatosis In A Large Healthy Brazilian Population, Sameer Shaharyar, Lara Roberson, Omar Jamal, Adnan Younus, Shozab Ali, Arthur Agatston, Khurram Nasir Baptist Health Medical Group

All Publications

BACKGROUND:Among the obese, the so-called metabolically healthy obese (MHO) phenotype is thought to confer a lower CVD risk as compared to obesity with typical associated metabolic changes. The present study aims to determine the relationship of different subtypes of obesity with inflammatory-cardiometabolic abnormalities.METHODS:We evaluated 5,519 healthy, Brazilian subjects (43 ± 10 years, 78% males), free of known cardiovascular disease. Those with (MRF) were considered metabolically healthy, and those with BMI ≥ 25 kg/m(2) and/or waist circumference meeting NCEP criteria for metabolic syndrome as overweight/obese (OW). High sensitivity C reactive protein (hsCRP) was measured to assess underlying inflammation and hepatic steatosis …

Remote Video Auditing With Real-Time Feedback In An Academic Surgical Suite Improves Safety And Efficiency Metrics: A Cluster Randomised Study, F. J. Overdyk, O. Dowling, S. Newman, D. Glatt, M. Chester, D. Armellino, B. Cole, G. S. Landis, D. Schoenfeld, J. F. Dicapua

Journal Articles

IMPORTANCE: Compliance with the surgical safety checklist during operative procedures has been shown to reduce inhospital mortality and complications but proper execution by the surgical team remains elusive. OBJECTIVE: We evaluated the impact of remote video auditing with real-time provider feedback on checklist compliance during sign-in, time-out and sign-out and case turnover times. DESIGN, SETTING: Prospective, cluster randomised study in a 23-operating room (OR) suite. PARTICIPANTS: Surgeons, anaesthesia providers, nurses and support staff. EXPOSURE: ORs were randomised to receive, or not receive, real-time feedback on safety checklist compliance and efficiency metrics via display boards and text messages, followed by a …

Association Between Respiratory Syncytial Virus Activity And Pneumococcal Disease In Infants: A Time Series Analysis Of Us Hospitalization Data., Daniel M. Weinberger, Keith P. Klugman, Claudia A. Steiner, Lone Simonsen, Cécile Viboud

Epidemiology Faculty Publications

BACKGROUND:

The importance of bacterial infections following respiratory syncytial virus (RSV) remains unclear. We evaluated whether variations in RSV epidemic timing and magnitude are associated with variations in pneumococcal disease epidemics and whether changes in pneumococcal disease following the introduction of seven-valent pneumococcal conjugate vaccine (PCV7) were associated with changes in the rate of hospitalizations coded as RSV.

METHODS AND FINDINGS:

We used data from the State Inpatient Databases (Agency for Healthcare Research and Quality), including >700,000 RSV hospitalizations and >16,000 pneumococcal pneumonia hospitalizations in 36 states (1992/1993-2008/2009). Harmonic regression was used to estimate the timing of the average seasonal …

Quality Control Measures Over 30 Years In A Multicenter Clinical Study: Results From The Diabetes Control And Complications Trial / Epidemiology Of Diabetes Interventions And Complications (Dcct/Edic) Study., Gayle M Lorenzi, Barbara H Braffett, Valerie L Arends, Ronald P Danis, Lisa Diminick, Kandace A Klumpp, Anthony D Morrison, Elsayed Z Soliman, Michael W Steffes, Patricia A Cleary

GW Biostatistics Center

No abstract provided.

The Cost-Effectiveness Of Diabetes Prevention: Results From The Diabetes Prevention Program And The Diabetes Prevention Program Outcomes Study, William Herman

GW Biostatistics Center

Background

The Diabetes Prevention Program (DPP) was a randomized, controlled clinical trial. It demonstrated that among high-risk individuals with impaired glucose tolerance, diabetes incidence was reduced by 58 % with lifestyle intervention and 31 % with metformin compared to placebo. During the Diabetes Prevention Program Outcomes Study (DPPOS), all DPP participants were unmasked to their treatment assignments, the original lifestyle intervention group was offered additional lifestyle support, the metformin group continued metformin, and all three groups were offered a group-implemented lifestyle intervention. Over the 10 years of combined DPP/DPPOS follow-up, diabetes incidence was reduced by 34 % in the lifestyle …

Reassessment Of Risk Genotypes (Grn, Tmem106b, And Abcc9 Variants) Associated With Hippocampal Sclerosis Of Aging Pathology, Peter T. Nelson, Wang-Xia Wang, Amanda B. Partch, Sarah E. Monsell, Otto Valladares, Sally R. Ellingson, Bernard R. Wilfred, Adam C. Naj, Li-San Wang, Walter A. Kukull, David W. Fardo

Pathology and Laboratory Medicine Faculty Publications

Hippocampal sclerosis of aging (HS-Aging) is a common high-morbidity neurodegenerative condition in elderly persons. To understand the risk factors for HS-Aging, we analyzed data from the Alzheimer’s Disease Genetics Consortium and correlated the data with clinical and pathologic information from the National Alzheimer’s Coordinating Center database. Overall, 268 research volunteers with HS-Aging and 2,957 controls were included; detailed neuropathologic data were available for all. The study focused on single-nucleotide polymorphisms previously associated with HS-Aging risk: rs5848 ( GRN ), rs1990622 ( TMEM106B ), and rs704180 ( ABCC9 ). Analyses of a subsample that was not previously evaluated (51 HS-Aging cases …

Promoting Colorectal Cancer Screening Among Haitian Americans, Steven S. Coughlin, Erica I. Lubetkin, Jennifer L. Hay, Renald Raphael, Selina A. Smith

Publications and Research

Background

Few studies have examined colorectal cancer screening among Haitian Americans, although striking disparities in colorectal cancer screening and mortality are well-documented among U.S. Blacks. Race, socioeconomic status, and place of birth are factors associated with colorectal cancer incidence and mortality patterns.

Methods

In this article, we summarize published studies on colorectal cancer screening among Haitian Americans, identified through bibliographic searches in PubMed and CINAHL through August 2015, and offer recommendations for further research.

Results

Only one qualitative study and three quantitative surveys have examined colorectal cancer screening among Haitian Americans. A qualitative study found important differences in perceptions of …