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BACKGROUND: The definition of health literacy has recently expanded beyond the idea of individual skills to include the system and environment the individual interacts with to receive care, known as organizational health literacy (OHL). However, neither the prevalence of OHL nor the impact of OHL on individuals' perceptions of their health and healthcare have been examined in New York's Medicaid managed care population. OBJECTIVE: This study aimed to estimate the prevalence of organizational health literacy in the New York State (NYS) Medicaid Managed Care (MMC) program. METHODS: A brief measure to assess organizational health literacy was developed from responses to two questions in the 2018 NYS Consumer Assessment of Healthcare Providers and Systems (CAHPS) survey. Generalized Estimating Equation models were developed to analyze the association between organizational health literacy and three aspects of perceptions of health and health care, controlling for demographic differences and clustering effects from health insurance plans. Missing data were handled using multiple imputation. KEY RESULTS: Among 3,598 members included in the study, 20% of the MMC members reported inadequate organizational health literacy. These members were more likely to be older, less educated, from racial and ethnic minority groups, and less fluent with English. They are more likely to have poorer self-reported health (odds ratio [OR] 1.49), lower perceived access to health care (OR 6.97), and lower satisfaction with their health care (OR 6.49) than members who did not report inadequate organizational health literacy. CONCLUSIONS: Our results suggest that a proportion of the NYS MMC population faces inadequate organizational health literacy, which can present a barrier to health care access and result in patients having a significantly poorer health care experience. Using an existing data source that is part of existing data collection allows for routine assessment of organizational health literacy, which can help inform health plans about areas for potential improvement. [HLRP: Health Literacy Research and Practice. 2023;7(3):e154-e164.].
PLAIN LANGUAGE SUMMARY: Our study looked at the impact of organizational health literacy on the perceptions of health and health care of NYS Medicaid Managed Care population. We used existing CAHPS questions to assess organizational health literacy and found that lower organizational health literacy led to worse perceptions of health and health care. This article illustrates an opportunity to demonstrate how organizational health literacy can be measured with annual CAHPS collections.
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Etnicidade , Letramento em Saúde , Estados Unidos , Humanos , Medicaid , Grupos Minoritários , New YorkRESUMO
Asian Americans are the fastest growing racial group in the USA, but their health disparities are often overlooked. Although their needs for transplantable organs are substantial, they have the lowest rates of organ donation per million compared to other Americans by race. To better understand Asian Americans' disposition toward organ donation, a self-administered survey was developed based on formative data collection and guidance from a Community Advisory Board composed of Asian American stakeholders. The instrument was deployed online, and quota sampling based on the 2017 American Community Survey was used to achieve a sample representative (N = 899) of the Asian American population. Bivariate tests using logistic regression and the chi-square test of independence were performed. Over half (58.1%) of respondents were willing to be organ donors. A majority (81.8%) expressed a willingness to donate a family member's organs, but enthusiasm depended on the family member's donor wishes. Only 9.5% of respondents indicated that the decision to donate their organs was theirs alone to make; the remainder would involve at least one other family member. Other key sociodemographic associations were found. This study demonstrates both the diversity of Asian Americans but also the centrality of the family's role in making decisions about organ donation. Practice and research considerations for the field are also presented.
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Asiático , Obtenção de Tecidos e Órgãos , Humanos , Asiático/psicologia , Asiático/estatística & dados numéricos , Família , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos e Questionários , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Doadores de TecidosRESUMO
STUDY QUESTION: Are follicular fluid (FF), arsenic (As), mercury (Hg), cadmium (Cd) and lead (Pb) concentrations associated with IVF outcomes among women undergoing IVF? SUMMARY ANSWER: There was a non-linear association between higher FF Hg concentration and a lower likelihood of biochemical pregnancy and live birth. Higher FF Pb concentration was also associated with a lower probability of live birth. WHAT IS KNOWN ALREADY: Previous research suggests that toxic elements may affect fertility among couples conceiving with and without assistance. However, the results have been inconsistent, possibly related in part to exposure misclassification. Very few studies have used ovarian FF to measure toxic elements, as it requires an invasive collection procedure, yet it may offer a more accurate estimate of a biologically effective dose than blood or urine. STUDY DESIGN SIZE DURATION: This is a prospective study of 56 women undergoing IVF, from October 2015 to June 2017. FF was collected for analysis on the day of oocyte retrieval. PARTICIPANTS/MATERIALS SETTING METHODS: As, Cd, Hg and Pb were determined in 197 FF specimens, using inductively coupled plasma tandem mass spectrometry. FF glutathione peroxidase, glutathione reductase, total glutathione-S-transferase, superoxide dismutase, arylesterase and paraoxonase (PON1p) activities were measured using kinetic enzyme assays. MAIN RESULTS AND THE ROLE OF CHANCE: Non-linear associations were detected, in which the probabilities of biochemical pregnancy (P = 0.05) and live birth (P = 0.05) were lower in association with FF Hg greater than â¼0.51 µg/l Hg, adjusted for age, race, cigarette smoking and recent seafood consumption. Higher FF Pb was also associated with a lower likelihood of live birth (relative risk (RR) = 0.68, 95% CI: 0.46, 1.00; P = 0.05). We also found a suggestive, although imprecise, antagonizing mediating effect of PON1p activity on the association between FF Pb and live birth (-28.3%; 95% CI: -358%, 270%). LIMITATIONS REASONS FOR CAUTION: The results should be interpreted judiciously given the limited sample size and difficulty accounting for correlated data in generalized additive models and mediation analyses. Additionally, women undergoing IVF are highly selected with respect to age and socioeconomic status, and so the generalizability of the results may be limited. WIDER IMPLICATIONS OF THE FINDINGS: Overall, the results suggest that FF Hg was associated with a lower likelihood of biochemical pregnancy and live birth, with a potential threshold effect, and that higher FF Pb was associated with a lower probability of live birth. These results may help to guide clinical recommendations for limiting the exposure of patients to Hg and Pb and ultimately improve IVF success rates. STUDY FUNDING/COMPETING INTERESTS: This work was funded in part by the National Institute of Environmental Health Sciences (NIEHS), grant number 1R56ES023886-01, to the University at Albany (M.S.B.), and in part by the National Institute of Environmental Health Sciences (NIEHS), grant number 1U2CES026542-01, to the Wadsworth Center (P.J.P.). The authors declare no competing interests. TRIAL REGISTRATION NUMBER: N/A.
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Both essential and non-essential elements have been associated with female reproductive function in epidemiologic investigations, including among IVF populations. To date, most investigators have used blood or urine to assess biomarkers of exposure, with few employing ovarian follicular fluid (FF). FF may offer a more direct "snapshot" of the oocyte microenvironment than blood or urine, however previous studies report follicle-to-follicle variability in FF constituents that may contribute to exposure misclassification. Our objectives were to investigate sources of trace element variability, to estimate FF biomarker reliability among women undergoing IVF (n = 34), and to determine the minimum number of follicles required to estimate subject-specific mean concentrations. We measured As, Hg, Cd, Pb, Cu, Mn, Se, and Zn in FF samples using inductively coupled plasma tandem mass spectrometry. Inter-subject (between-women) variability contributed most of the variability in FF element concentrations, with ovarian, follicular, and analytical as smaller sources of variability. The proportion of variability attributable to sources between-follicles differed by age, body mass index (BMI), race, and cigarette smoking for Cu, Se, and Zn, by BMI and cigarette smoking for As, by primary infertility diagnosis for Hg, Cu, Se, and Zn, and by ovarian stimulation protocol for Mn and Se. Four to five individual follicles were sufficient to estimate subject-specific mean Cu, Se, and Zn concentrations, while >14 were necessary for As, Hg, Cd, Pb, and Mn. Overall, our results suggest that FF is a suitable source of biomarkers of As and Hg exposure in ovarian follicles. Although limited in size, our study offers the most comprehensive exploration of biological variation in FF trace elements to date and may provide guidance for future studies of ovarian trace element exposures.
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Líquido Folicular/metabolismo , Reprodutibilidade dos Testes , Oligoelementos/metabolismo , Adulto , Feminino , Fertilização in vitro , Líquido Folicular/química , Humanos , Mercúrio/análise , Oócitos , Folículo Ovariano , Oligoelementos/análiseRESUMO
Human exposure to non-essential toxic metals such as cadmium (Cd), mercury (Hg), and lead (Pb), and metalloids such as arsenic (As) commonly occurs through diet. Toxic trace element exposures have been reported in association with fertility and fecundity in epidemiologic studies even at low to moderate levels. While most previous studies employed blood and urine biomarkers of exposure, few have assessed toxic trace elements in ovarian follicular fluid (FF), which surrounds the developing oocyte and hence may better reflect concentrations potentially affecting reproductive outcomes. Our objective was to identify dietary predictors of FF toxic trace elements in n = 56 women (mean age: 38.3 years) undergoing in vitro fertilization (IVF) at the University of California at San Francisco. We determined As, Hg, Cd, and Pb in 197 FF specimens, collected on the day of oocyte retrieval, using inductively coupled plasma tandem mass spectrometry. A comprehensive food frequency questionnaire was used to assess the weekly and annual dietary "patterns" of participants. Consumption of specific seafood items and turkey were correlated with individual FF toxic trace elements. We also found that each unit higher seafood consumption in the past week dominated by mollusks, shrimp, and bass was associated with 60% higher FF As (95% confidence interval (CI): 25%, 105%) and FF Hg (95%CI: 7%, 136%) concentrations. Higher annual seafood consumption dominated by urchin, crab, and trout was associated with 16% higher FF As (95%CI: -2%, 38%) and 31% higher FF Hg (95%CI: 7%, 60%) concentrations per unit intake. No associations were noted between diet and Cd and Pb levels in FF. Overall, our results suggest that higher seafood consumption contributes to elevated levels of As and Hg in FF. These findings are consistent with previous IVF studies that assessed toxic trace element exposures in blood and urine. To our knowledge, this is the first study to report that diet might be a source of As, Hg, Cd, and Pb in FF.
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Arsênio , Mercúrio , Adulto , Animais , Cádmio , Feminino , Fertilização in vitro , Líquido Folicular , Humanos , Alimentos Marinhos/análiseRESUMO
This study examines Muslim-non-Muslim disparities in locational attainment. We pool data from the 2004, 2006, and 2008 waves of the Public Health Management Corporation's Southeastern Pennsylvania Household Survey. These data contain respondents' religious identities and are geocoded at the census-tract level, allowing us to merge American Community Survey data and examine neighborhood-level outcomes to gauge respondents' locational attainment. Net of controls, our multivariate analyses reveal that among blacks and nonblacks, Muslims live in neighborhoods that have significantly lower shares of whites and greater representations of blacks. Among blacks, Muslims are significantly less likely than non-Muslims to reside in suburbs. The Muslim disadvantages for blacks and nonblacks in neighborhood poverty and neighborhood median income, however, become insignificant. Our results provide support for the tenets of the spatial assimilation and place stratification models and suggest that Muslim-non-Muslim disparities in locational attainment define a new fault line in residential stratification.
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Islamismo , Áreas de Pobreza , Características de Residência/estatística & dados numéricos , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Philadelphia , Fatores Socioeconômicos , Análise EspacialRESUMO
Experimental and observational data implicate phthalates as developmental toxicants. However, few data are available to assess the maternal risks of gestational exposure by race and infant sex. To begin to address this data gap, we characterized associations between maternal urinary phthalate metabolites and birth outcomes among African American and white mothers from a southeastern U.S. population. We enrolled pregnant African American (nâ¯=â¯152) and white (nâ¯=â¯158) women with singleton live births between 18 and 22â¯weeks gestation. We measured phthalate metabolites (mono-n-butyl phthalate (MBP), monoisobutyl phthalate (MiBP), monobenzyl phthalate (MBzP), mono(2-ethylhexyl) phthalate (MEHP), mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), mono-2-ethyl-5-hydroxyhexyl phthalate (MEHHP), monoethyl phthalate (MEP), monomethyl phthalate (MMP), and the sums of DEHP (ΣDEHP) and DBP (ΣDBP) metabolites) in up to two gestational urine specimens from mothers, and evaluated confounder-adjusted associations per natural log unit greater concentration with birth weight for gestational age z-score, small for gestational age (SGA; <10th %tile), preterm birth (PTB; <37â¯weeks gestation), and low birth weight (LBW; <2500â¯g). We also tested for interactions by maternal race and infant sex. We found that lower z-scores were associated with greater MiBP (ßâ¯=â¯-0.28; 95% CI: -0.54, -0.02) and MMP (ßâ¯=â¯-0.30; 95% CI: -0.52, -0.09) concentrations, while MEP interacted with race (pâ¯=â¯0.04), indicating an association among whites (ßâ¯=â¯-0.14; 95% CI: -0.28, 0.001) but not among African Americans (ßâ¯=â¯0.05; 95% CIâ¯=â¯-0.09, 0.19). Greater MiBP (ORâ¯=â¯2.82; 95% CI: 1.21, 6.56) and MEOHP (ORâ¯=â¯2.80; 95% CI: 1.05, 7.42) were associated with an overall higher SGA risk, greater MEHP was associated with higher SGA risk (pâ¯=â¯0.10) in whites (ORâ¯=â¯3.26 95% CI: 0.64, 16.56) but not in African Americans (ORâ¯=â¯0.71 95% CI: 0.07, 7.17), and the associations for MiBP (pâ¯=â¯0.02) and ΣDBP (pâ¯=â¯0.02) varied by infant sex. We detected interactions for PTB in which African Americans were at higher risk than whites for greater MiBP (pâ¯=â¯0.08) and MEP (pâ¯=â¯0.02) although lower risk for greater MEHP (pâ¯=â¯0.09). Greater MEP was associated with an overall higher LBW risk (ORâ¯=â¯1.33; 95% CI: 0.95, 1.86), and males were at higher risk than females with greater MBP (pâ¯=â¯0.002), MiBP (pâ¯=â¯0.02), MBzP (pâ¯=â¯0.01), MEP (pâ¯=â¯0.002), MMP (pâ¯=â¯0.09), and ΣDBP (pâ¯=â¯0.01) concentrations. Overall, our results suggest that gestational phthalate exposure is associated with adverse maternal birth outcomes, and that the effects vary by maternal race and infant sex.
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Desenvolvimento Fetal , Exposição Materna , Adolescente , Adulto , Peso ao Nascer , Feminino , Humanos , Masculino , Ácidos Ftálicos , Gravidez , Adulto JovemRESUMO
INTRODUCTION: Metabolic syndrome (MetS), a clustering of cardiometabolic risk factors of type 2 diabetes and cardiovascular disease, disproportionately affects Asian Indians (AIs). We examined prevalence of MetS using 3 ethnicity-specific MetS criteria among immigrant AIs in the United States. We also examined associations between MetS and health promotion behaviors. OBJECTIVE: To present MetS prevalence estimates by the 3 ethnicity-specific criteria and investigate differences in health promotion behaviors among AIs with and without MetS to highlight the critical need for lifestyle modification strategies for this population. DESIGN: We analyzed data from a national cross-sectional study of 1037 AIs in the United States (2004-2006). We used the consensus criteria, International Diabetes Federation criteria, and modified criteria to estimate MetS prevalence. The Health Promotion Lifestyle Profile II scale measured health promotion behaviors. Bioclinical data (fasting blood glucose, triglyceride levels) were collected. Directed acyclic graphs and Likelihood Ratio Test assisted with model selection. Multiple imputation inference incorporated uncertainty due to missing data and made use of all available data. Adjusted multivariable logistic regression analysis tested for associations. RESULTS: Out of all participants, 40.3% met the consensus criteria, 34.8% met the International Diabetes Federation criteria, and 52.5% met the modified criteria. We found no statistically significant associations between engagement in health promotion measures and the prevalence of MetS and its criteria. CONCLUSION: Our study confirmed the high prevalence of MetS in the immigrant AI population in the United States. Our results showed that AIs with MetS did not exhibit an increased level of engagement in health promotion behaviors. We recommend continued refining of criteria for diagnosis and culturally suitable, age-appropriate strategies to increase engagement in healthier lifestyles among this high-risk population.
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Asiático/estatística & dados numéricos , Síndrome Metabólica/diagnóstico , Adulto , Asiático/genética , Povo Asiático/etnologia , Povo Asiático/genética , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Masculino , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/etnologia , Pessoa de Meia-Idade , Prevalência , Estados UnidosRESUMO
BACKGROUND: Skeletal muscle dysfunction occurring as a result of ICU admission associates with higher mortality. Although preadmission higher BMI correlates with better outcomes, the impact of baseline muscle and fat mass has not been defined. We therefore investigated the association of skeletal muscle and fat mass at ICU admission with survival and disability at hospital discharge. METHODS: This single-center, prospective, observational cohort study included medical ICU (MICU) patients from an academic institution in the Unites States. A total of 401 patients were evaluated with pectoralis muscle area (PMA) and subcutaneous adipose tissue (SAT) determinations conducted by CT scanning at the time of ICU admission, which were later correlated with clinical outcomes accounting for potential confounders. RESULTS: Larger admission PMA was associated with better outcomes, including higher 6-month survival (OR, 1.03; 95% CI, 1.01-1.04; P < .001), lower hospital mortality (OR, 0.96; 95% CI, 0.93-0.98; P < .001), and more ICU-free days (slope, 0.044 ± 0.019; P = .021). SAT was not significantly associated with any of the measured outcomes. In multivariable analyses, PMA association persisted with 6 months and hospital survival and ICU-free days, whereas SAT remained unassociated with survival or other outcomes. PMA was not associated with regaining of independence at the time of hospital discharge (OR, 0.99; 95% CI, 0.98-1.01; P = .56). CONCLUSIONS: In this study cohort, ICU admission PMA was associated with survival during and following critical illness; it was unable to predict regaining an independent lifestyle following discharge. ICU admission SAT mass was not associated with survival or other measured outcomes.
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Índice de Massa Corporal , Estado Terminal/mortalidade , Hospitalização , Unidades de Terapia Intensiva , Adiposidade , Adulto , Idoso , Estudos de Coortes , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético , Gordura Subcutânea , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: Compared with pulmonary sarcoidosis, sarcoidosis without lung involvement may involve other immunopathologic mechanisms and be associated with other demographic and clinical features. METHODS: This was a retrospective analysis of clinical data collected in real time on 1,686 patients with biopsy-proven sarcoidosis from two large university sarcoidosis outpatient clinics in the United States. We compared differences in demographics characteristics and clinical presentation between pulmonary and nonpulmonary sarcoidosis (NPS). Patients were considered to have NPS only if they had normal chest imaging and no features consistent with pulmonary involvement on the basis of currently accepted criteria. RESULTS: A total of 8.3% of this sarcoidosis cohort met criteria for NPS. NPS was significantly more common in white than black patients, and more common in women than men. The skin was the most common organ involved, and was observed in nearly one-half of patients with NPS. Isolated skin sarcoidosis was the overwhelmingly most common pattern of organ involvement seen in the NPS group (25%), and no other pattern of involvement was found in more than 5% of patients with NPS. CONCLUSIONS: Significant demographic and sex differences were observed between patients with pulmonary and nonpulmonary sarcoidosis. These differences reflect previous data concerning differences between patients with skin and lung sarcoidosis because the skin was the major organ involved with NPS. Although the lungs are likely the primary site of exposure in pulmonary sarcoidosis, the high prevalence of skin involvement in NPS suggests the skin is the most conducive site of antigen capture outside of the respiratory tract.
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Sarcoidose/patologia , Adulto , Biópsia , Feminino , Humanos , Masculino , Estudos Retrospectivos , Sarcoidose/diagnóstico por imagem , Sarcoidose/etnologia , Sarcoidose Pulmonar/diagnóstico por imagem , Sarcoidose Pulmonar/etnologia , Sarcoidose Pulmonar/patologia , Fatores Sexuais , South Carolina , Estados UnidosRESUMO
PURPOSE: Perfluoroalkyl substances (PFASs) are environmentally persistent amphiphilic compounds. Exposure to two PFASs, perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) is linked to specific occupations and industries. This study examines the contribution of past occupational PFAS exposure to serum PFOS and PFOA levels among 154 older adults in New York State. METHODS: Serum PFOS and PFOA levels were compared to data from the National Health and Nutrition Examination Survey (NHANES). Potential occupational exposure to any PFAS was determined from work histories, reviewed by an industrial hygienist, and assessed in relation to current serum PFOS and PFOA levels using exposure probability, duration and cumulative exposure. RESULTS: We observed 25% higher serum PFOS and 80% higher PFOA levels in study participants compared to NHANES. No participants reported PFAS chemical manufacturing work, but n = 68 reported work in occupations and industries known to use PFASs. We found that participants with high cumulative workplace exposure had 34% higher serum PFOS levels compared to participants without occupational exposure, adjusted for age, sex and income. Serum PFOS levels were 26% higher for participants with longer occupational exposure durations. The probability of occupational PFAS exposure metric was not associated with serum PFOS. Serum PFOA was not associated with any measure of occupational exposure. CONCLUSION: Occupational exposure may contribute to total PFOS body burden in this study population, even among workers not directly involved in manufacturing PFASs. PFAS exposure assessments should evaluate the workplace as a potential source, even when workplace exposures are assumed to be low or moderate.
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Ácidos Alcanossulfônicos/sangue , Caprilatos/sangue , Exposição Ambiental/análise , Fluorocarbonos/sangue , Inquéritos Nutricionais/estatística & dados numéricos , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , New York , Exposição Ocupacional/análise , Estudos Retrospectivos , Fatores Sexuais , Fatores Socioeconômicos , Fatores de TempoRESUMO
PURPOSE: Cough is a common symptom of pulmonary sarcoidosis. We analyzed the severity of cough and factors associated with cough in a university sarcoidosis clinic cohort. METHODS: Consecutive patients completed the Leicester Cough Questionnaire (LCQ) and a cough visual analog scale (VAS). Clinical and demographic data were collected. Means of the LCQ were analyzed in patients who had multiple visits in terms of constant variables (e.g., race, sex). RESULTS: 355 patients completed the LCQ and VAS at 874 visits. Cough was significantly worse in blacks than whites as determined by the LCQ-mean (16.5 ± 2.6 vs. 17.8 ± 3.0, p < 0.001) and VAS-mean (3.8 ± 3.0 vs. 2.0 ± 2.6, p < 0.0001). Cough was worse in women than men as measured by the VAS-mean (2.7 ± 2.9 vs. 2.2 ± 2.7, p = 0.002), one of the LCQ-mean domains (LCQ-Social-mean 5.4 ± 0.9 vs. 5.2 ± 1.0, p = 0.03), but not the total LCQ-mean score. Cough was not significantly different by either measure in terms of smoking status, age, or spirometric parameter (FVC % predicted, FEV1 % predicted, FEV1/FVC). In a multivariable linear regression analysis, cough was significantly worse in blacks than whites and in pulmonary sarcoidosis than non-pulmonary sarcoidosis with both cough measures, in women than men for the VAS only, and not for spirometric parameters, Scadding stage, or age. The LCQ and VAS were strongly correlated. CONCLUSIONS: In a large university outpatient sarcoidosis cohort, cough was worse in blacks than whites. Cough was not statistically significantly different in terms of age, spirometric measures, Scadding stage, or smoking status. The LCQ correlated strongly with a visual analog scale for cough.
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Tosse/fisiopatologia , Sarcoidose Pulmonar/fisiopatologia , Adulto , Negro ou Afro-Americano , Fatores Etários , Idoso , Tosse/etnologia , Tosse/etiologia , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Sarcoidose Pulmonar/complicações , Fatores Sexuais , Inquéritos e Questionários , Escala Visual Analógica , População BrancaRESUMO
PURPOSE: The purpose of this study was to examine the biological variability of follicular fluid (FF) high density lipoprotein (HDL) particle components measured in ipsilateral ovarian follicles. METHODS: We collected FF from two ipsilateral follicles among six women undergoing in vitro fertilization (IVF). We measured concentrations of 19 FF HDL particle components, including HDL cholesterol, free cholesterol, four cholesteryl esters, phospholipids, triglycerides, paraoxonase and arylesterase activities, apolipoproteins A-1 and A-2 (ApoA-1 and ApoA-2), and seven lipophilic micronutrients, by automated analysis and with high-performance liquid chromatography. We assessed biological variability using two-stage nested analysis of variance and compared values with those previously published for contralateral follicles. RESULTS: For most FF HDL analytes, there was little variability between follicles relative to the variability between women (i.e., %σ(2) F:%σ(2) B <0.5). Intraclass correlation coefficients were >0.80 for HDL cholesterol (0.82), phospholipids (0.89), paraoxonase (0.96), and arylesterase (0.91) activities, ApoA-1 (0.89), and ApoA-2 (0.90), and single specimen collections were required to estimate the subject-specific mean, demonstrating sufficient reliability for use as biomarkers of the follicular microenvironment in epidemiologic and clinical studies. CONCLUSIONS: These preliminary results raise the possibility for tighter regulation of HDL in follicles within the same ovary vs. between ovaries. Thus, collection of a single FF specimen may be sufficient to estimate HDL particle components concentrations within a single ovary. However, our results should be interpreted with caution as the analysis was based on a small sample.
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Líquido Folicular/metabolismo , Lipoproteínas HDL/análise , Adulto , Feminino , Fertilização in vitro/métodos , Líquido Folicular/química , Humanos , Lipoproteínas HDL/química , Lipoproteínas HDL/metabolismo , Folículo Ovariano/metabolismoRESUMO
Modern statistical methods using incomplete data have been increasingly applied in a wide variety of substantive problems. Similarly, receiver operating characteristic (ROC) analysis, a method used in evaluating diagnostic tests or biomarkers in medical research, has also been increasingly popular problem in both its development and application. While missing-data methods have been applied in ROC analysis, the impact of model mis-specification and/or assumptions (e.g. missing at random) underlying the missing data has not been thoroughly studied. In this work, we study the performance of multiple imputation (MI) inference in ROC analysis. Particularly, we investigate parametric and non-parametric techniques for MI inference under common missingness mechanisms. Depending on the coherency of the imputation model with the underlying data generation mechanism, our results show that MI generally leads to well-calibrated inferences under ignorable missingness mechanisms.
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INTRODUCTION: Few studies have analyzed the cohort effects of lifecourse socioeconomic position (SEP) on racial disparities in body mass index (BMI) trajectories. We assessed the contribution of lifecourse SEP on racial differences in BMI trajectories among two different age cohorts of women. METHODS: Four waves of the Americans' Changing Lives' study (1986-2002) were used to compute BMI trajectories for 2194 Black and White women. Multivariable associations of lifecourse SEP variables (father's education, perceived childhood family status, education, income, wealth and financial security) with Wave 1(W1) BMI and BMI change were assessed using mixed models. RESULTS: Black women had higher W1 BMI than White women in both cohorts (women <40 years in 1986 (+2.6 kg/m2 (95%CI: +1.71, +3.53)) and women>=40 in 1986 (+2.68 kg/m2 (95%CI:+2.12,3.24))); Black women in the younger cohort had a higher change in BMI (+0.73 kg/m2/year (95%CI:+0.17,+1.29)). High education was associated with lower W1 BMI in both cohorts (-1.34 (95%CI:-2.53,-0.15) and -1.08 kg/m2 (95%CI:-0.50,-1.65), respectively). Among the younger cohort, high income was associated with lower W1 BMI (-0.78kg/m2/unit log income (95%CI:-1.32,-0.25)) while among the older cohort, high father's education (-0.78 kg/m2 (95%CI:-0.06,-1.50)) and higher wealth (-0.26 kg/m2(95%CI:-0.43,-0.08))were associated with low W1 BMI. Racial disparities in W1 BMI were attenuated by 20-25% while those for BMI change remained unexplained on adjustment for lifecourse SEP. CONCLUSION: In this large population-based dataset, results suggest that the contribution of lifecourse SEP to racial disparities in BMI may be established early in adulthood.
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OBJECTIVE: The aim of this study is to evaluate the association between lifecourse socioeconomic position (SEP) and changes in body mass index (BMI), and assess disparities in these associations across racial/ethnic groups. METHODS: With longitudinal data from 4 waves of the Americans' Changing Lives Study (1986-2002), we employed mixed-effects modeling to estimate BMI trajectories for 1174 Blacks and 2323 White adults. We also estimated associations between these trajectories and lifecourse SEP variables, including father's education, perceived childhood SEP, own education, income, wealth, and financial security. RESULTS: Blacks had higher baseline BMIs, and steeper increases in BMI, compared to Whites. Childhood SEP, as measured by high father's education, was associated with lower baseline BMI among Whites. High education was associated with a lower baseline BMI within both race and sex categories. Income had contrasting effects among men and women. Higher income was associated with higher BMI only among males. Associations between indicators of SEP and BMI trajectories were only found for Whites. CONCLUSIONS: Our study demonstrates that lifecourse SEP may influence adult BMI differently within different racial and sex groups.
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Índice de Massa Corporal , Obesidade/etnologia , Grupos Raciais , Fatores Socioeconômicos , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Fatores Etários , Idoso , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , População Branca/estatística & dados numéricos , Adulto JovemRESUMO
The multivariate normal (MVN) distribution is arguably the most popular parametric model used in imputation and is available in most software packages (e.g., SAS PROC MI, R package norm). When it is applied to categorical variables as an approximation, practitioners often either apply simple rounding techniques for ordinal variables or create a distinct 'missing' category and/or disregard the nominal variable from the imputation phase. All of these practices can potentially lead to biased and/or uninterpretable inferences. In this work, we develop a new rounding methodology calibrated to preserve observed distributions to multiply impute missing categorical covariates. The major attractiveness of this method is its flexibility to use any 'working' imputation software, particularly those based on MVN, allowing practitioners to obtain usable imputations with small biases. A simulation study demonstrates the clear advantage of the proposed method in rounding ordinal variables and, in some scenarios, its plausibility in imputing nominal variables. We illustrate our methods on a widely used National Survey of Children with Special Health Care Needs where incomplete values on race posed a valid threat on inferences pertaining to disparities.
Assuntos
Inquéritos Epidemiológicos/estatística & dados numéricos , Análise Multivariada , Avaliação das Necessidades/estatística & dados numéricos , Distribuição Normal , Adolescente , Viés , Criança , Pré-Escolar , Simulação por Computador , Feminino , Pesquisas sobre Atenção à Saúde/estatística & dados numéricos , Disparidades nos Níveis de Saúde , Disparidades em Assistência à Saúde/estatística & dados numéricos , Humanos , Lactente , Masculino , Grupos Raciais/estatística & dados numéricos , Software/estatística & dados numéricosRESUMO
Owing to its practicality as well as strong inferential properties, multiple imputation has been increasingly popular in the analysis of incomplete data. Methods that are not only computationally elegant but also applicable in wide spectrum of statistical incomplete data problems have also been increasingly implemented in a numerous computing environments. Unfortunately, however, the speed of this development has not been replicated in reaching to "sophisticated" users. While the researchers have been quite successful in developing the underlying software, documentation in a style that would be most reachable to the greater scientific society has been lacking. The main goal of this special volume is to close this gap by articles that illustrate these software developments. Here I provide a brief history of multiple imputation and relevant software and highlight the contents of the contributions. Potential directions for the future of the software development is also provided.
RESUMO
Principled techniques for incomplete-data problems are increasingly part of mainstream statistical practice. Among many proposed techniques so far, inference by multiple imputation (MI) has emerged as one of the most popular. While many strategies leading to inference by MI are available in cross-sectional settings, the same richness does not exist in multilevel applications. The limited methods available for multilevel applications rely on the multivariate adaptations of mixed-effects models. This approach preserves the mean structure across clusters and incorporates distinct variance components into the imputation process. In this paper, I add to these methods by considering a random covariance structure and develop computational algorithms. The attraction of this new imputation modeling strategy is to correctly reflect the mean and variance structure of the joint distribution of the data, and allow the covariances differ across the clusters. Using Markov Chain Monte Carlo techniques, a predictive distribution of missing data given observed data is simulated leading to creation of multiple imputations. To circumvent the large sample size requirement to support independent covariance estimates for the level-1 error term, I consider distributional impositions mimicking random-effects distributions assigned a priori. These techniques are illustrated in an example exploring relationships between victimization and individual and contextual level factors that raise the risk of violent crime.
RESUMO
Multivariate extensions of well-known linear mixed-effects models have been increasingly utilized in inference by multiple imputation in the analysis of multilevel incomplete data. The normality assumption for the underlying error terms and random effects plays a crucial role in simulating the posterior predictive distribution from which the multiple imputations are drawn. The plausibility of this normality assumption on the subject-specific random effects is assessed. Specifically, the performance of multiple imputation created under a multivariate linear mixed-effects model is investigated on a diverse set of incomplete data sets simulated under varying distributional characteristics. Under moderate amounts of missing data, the simulation study confirms that the underlying model leads to a well-calibrated procedure with negligible biases and actual coverage rates close to nominal rates in estimates of the regression coefficients. Estimation quality of the random-effect variance and association measures, however, are negatively affected from both the misspecification of the random-effect distribution and number of incompletely-observed variables. Some of the adverse impacts include lower coverage rates and increased biases.