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1.
Health Place ; 64: 102385, 2020 07.
Article in English | MEDLINE | ID: mdl-32755812

ABSTRACT

Structural racism, evidenced in practices like residential racial segregation, has been linked to health inequities. We examined the relationship between an adverse environmental factor (alcohol outlet overconcentration), segregated neighborhoods, and county alcohol policy in Louisiana and Alabama to investigate this link. Multilevel analysis revealed high outlet density associated with segregated counties and predominantly black census tracts in counties with restrictive alcohol policy. This inverse association between policies designed to limit alcohol availability and overconcentration of outlets in black neighborhoods warrants consideration by policymakers given links between outlet density and health inequities. Consideration of these findings in historical context suggests these policies may function as a contemporary actualization of the historical use of alcohol policy to subjugate black people in the South, now over-concentrating instead of prohibiting access.


Subject(s)
Racism , Black or African American , Humans , Louisiana , Policy , Residence Characteristics
2.
Front Public Health ; 7: 18, 2019.
Article in English | MEDLINE | ID: mdl-30834239

ABSTRACT

Triple Negative Breast Cancer (TNBC) is an aggressive, heterogeneous subtype of breast cancer, which is more frequently diagnosed in African American (AA) women than in European American (EA) women. The purpose of this study is to investigate the role of social determinants in racial disparities in TNBC. Data on Louisiana TNBC patients diagnosed in 2010-2012 were collected and geocoded to census tract of residence at diagnosis by the Louisiana Tumor Registry. Using multilevel statistical models, we analyzed the role of neighborhood concentrated disadvantage index (CDI), a robust measure of physical and social environment, in racial disparities in TNBC incidence, stage at diagnosis, and stage-specific survival for the study population. Controlling for age, we found that AA women had a 2.21 times the incidence of TNBC incidence compared to EA women. Interestingly, the incidence of TNBC was independent of neighborhood CDI and adjusting for neighborhood environment did not impact the observed racial disparity. AA women were more likely to be diagnosed at later stages and CDI was associated with more advanced stages of TNBC at diagnosis. CDI was also significantly associated with poorer stage-specific survival. Overall, our results suggest that neighborhood disadvantage contributes to racial disparities in stage at diagnosis and survival among TNBC patients, but not to disparities in incidence of the disease. Further research is needed to determine the mechanisms through which social determinants affect the promotion and progression of this disease and guide efforts to improve overall survival.

3.
Front Oncol ; 8: 375, 2018.
Article in English | MEDLINE | ID: mdl-30254987

ABSTRACT

Purpose: Over the past three decades, Hepatocellular Carcinoma (HCC) is one of few cancers for which incidence has increased in the United States (US). It is likely social determinants at the population level are driving this increase. We designed a population-based study to explore whether social determinants at the neighborhood level are geographically associated with HCC incidence in Louisiana by examining the association of HCC incidence with neighborhood concentrated disadvantage. Methods: Primary HCC cases diagnosed from 2008 to 2012 identified from the Louisiana Tumor Registry were geocoded to census tract of residence at the time of diagnosis. Neighborhood concentrated disadvantage index (CDI) for each census tract was calculated according to the PhenX Toolkit data protocol based on population and socioeconomic measures from the US Census. The incidence of HCC was modeled using multilevel binomial regression with individuals nested within neighborhoods. Results: The study included 1,418 HCC cases. Incidence of HCC was greater among males than females and among black than white. In multilevel models controlling for age, race, and sex, neighborhood CDI was positively associated with the incidence of HCC. A one standard deviation increase in CDI was associated with a 22% increase in HCC risk [Risk Ratio (RR) = 1.22; 95% CI (1.15, 1.31)]. Adjusting for contextual effects of an individual's neighborhood reduced the disparity in HCC incidence. Conclusion: Neighborhood concentrated disadvantage, a robust measure of an adverse social environment, was found to be a geographically associated with HCC incidence. Differential exposure to neighborhoods characterized by concentrated disadvantage partially explained the racial disparity in HCC for Louisiana. Our results suggest that increasing rates of HCC, and existing racial disparities for the disease, are partially explained by measures of an adverse social environment.

4.
Ann Epidemiol ; 28(5): 316-321.e2, 2018 05.
Article in English | MEDLINE | ID: mdl-29678311

ABSTRACT

PURPOSE: Colorectal cancer (CRC) continues to demonstrate racial disparities in incidence and survival in the United States. This study investigates the role of neighborhood concentrated disadvantage in racial disparities in CRC incidence in Louisiana. METHODS: Louisiana Tumor Registry and U.S. Census data were used to assess the incidence of CRC diagnosed in individuals 35 years and older between 2008 and 2012. Neighborhood concentrated disadvantage index (CDI) was calculated based on the PhenX Toolkit protocol. The incidence of CRC was modeled using multilevel binomial regression with individuals nested within neighborhoods. RESULTS: Our study included 10,198 cases of CRC. Adjusting for age and sex, CRC risk was 28% higher for blacks than whites (risk ratio [RR] = 1.28; 95% confidence interval [CI] = 1.22-1.33). One SD increase in CDI was associated with 14% increase in risk for whites (RR = 1.14; 95% CI = 1.10-1.18) and 5% increase for blacks (RR = 1.05; 95% CI = 1.02-1.09). After controlling for differential effects of CDI by race, racial disparities were not observed in disadvantaged areas. CONCLUSION: CRC incidence increased with neighborhood disadvantage and racial disparities diminished with mounting disadvantage. Our results suggest additional dimensions to racial disparities in CRC outside of neighborhood disadvantage that warrants further research.


Subject(s)
Colorectal Neoplasms/epidemiology , Health Status Disparities , Healthcare Disparities/statistics & numerical data , Residence Characteristics , Social Determinants of Health , Adult , Aged , Colorectal Neoplasms/ethnology , Female , Healthcare Disparities/ethnology , Humans , Incidence , Louisiana/epidemiology , Male , Middle Aged , Socioeconomic Factors
5.
Spat Spatiotemporal Epidemiol ; 21: 13-23, 2017 06.
Article in English | MEDLINE | ID: mdl-28552184

ABSTRACT

Research shows aconsistent racial disparity in obesity between white and black adults in the United States. Accounting for the disparity is a challenge given the variety of the contributing factors, the nature of the association, and the multilevel relationships among the factors. We used the multivariable mediation analysis (MMA) method to explore the racial disparity in obesity considering not only the individual behavior but also geospatially derived environmental risk factors. Results from generalized linear models (GLM) were compared with those from multiple additive regression trees (MART) which allow for hierarchical data structure, and fitting of nonlinear and complex interactive relationships. As results, both individual and geographically defined factors contributed to the racial disparity in obesity. MART performed better than GLM models in that MART explained a larger proportion of the racial disparity in obesity. However, there remained disparities that cannot be explained by factors collected in this study.


Subject(s)
Black or African American/statistics & numerical data , Environment , Geography , Obesity/epidemiology , Racial Groups/statistics & numerical data , White People/statistics & numerical data , Adult , Aged , Aged, 80 and over , Female , Humans , Linear Models , Male , Middle Aged , Multivariate Analysis , Risk Factors , Socioeconomic Factors , United States/epidemiology
6.
Am J Prev Med ; 52(1S1): S13-S19, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27989288

ABSTRACT

INTRODUCTION: There is growing recognition that health disparities research needs to incorporate social determinants in the local environment into explanatory models. In the transdisciplinary setting of the Mid-South Transdisciplinary Collaborative Center (TCC), the Social Determinants of Health (SDH) Core developed an approach to incorporating SDH across a variety of studies. This place-based approach, which is geographically based, transdisciplinary, and inherently multilevel, is discussed. METHODS: From 2014 through 2016, the SDH Core consulted on a variety of Mid-South TCC research studies with the goal of incorporating social determinants into their research designs. The approach used geospatial methods (e.g., geocoding) to link individual data files with measures of the physical and social environment in the SDH Core database. Once linked, the method permitted various types of analysis (e.g., multilevel analysis) to determine if racial disparities could be explained in terms of social determinants in the local environment. RESULTS: The SDH Core consulted on five Mid-South TCC research projects. In resulting analyses for all the studies, a significant portion of the variance in one or more outcomes was partially explained by a social determinant from the SDH Core database. CONCLUSIONS: The SDH Core approach to addressing health disparities by linking neighborhood social and physical environment measures to an individual-level data file proved to be a successful approach across Mid-South TCC research projects.


Subject(s)
Community-Based Participatory Research/methods , Health Status Disparities , Residence Characteristics , Social Determinants of Health , Social Environment , Humans , Research Design , Socioeconomic Factors
7.
Am J Prev Med ; 52(1S1): S40-S47, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27989291

ABSTRACT

INTRODUCTION: This study aimed to determine the feasibility of using electronic health record (EHR) data from a federally qualified health center (FQHC) to assess the association between street connectivity, a measure of walkability for the local environment, and BMI obtained from EHRs. METHODS: The study included patients who visited Daughters of Charity clinics in 2012-2013. A total of 31,297 patients were eligible, of which 28,307 were geocoded. BMI and sociodemographic information were compiled into a de-identified database. The street connectivity measure was intersection density, calculated as the number of three-way or greater intersections per unit area. Multilevel analyses of BMI, measured on 17,946 patients who were aged ≥20 years, not pregnant, had complete sociodemographic information, and a BMI value that was not considered an outlier, were conducted using random intercept models. RESULTS: Overall, on average, patients were aged 44.1 years, had a BMI of 30.2, and were mainly non-Hispanic black (59.4%). An inverse association between BMI and intersection density was observed in multilevel models controlling for age, gender, race, and marital status. Tests for multiple interactions were conducted and a significant interaction between race and intersection density indicated the decrease in BMI was strongest for non-Hispanic whites (decreased by 2) compared with blacks or Hispanics (decreased by 0.6) (p=0.0121). CONCLUSIONS: EHRs were successfully used to assess the relationship between street connectivity and BMI in a multilevel framework. Increasing street connectivity levels measured as intersection density were inversely associated with directly measured BMI obtained from EHRs, demonstrating the feasibility of the approach.


Subject(s)
Body Mass Index , Environment Design , Obesity/epidemiology , Walking , Adult , Community Health Centers/statistics & numerical data , Electronic Health Records/statistics & numerical data , Feasibility Studies , Female , Humans , Louisiana , Male , Middle Aged , Risk Assessment/methods
8.
PLoS One ; 11(12): e0168364, 2016.
Article in English | MEDLINE | ID: mdl-27992587

ABSTRACT

Low unit response rates can increase bias and compromise study validity. Response rates have continued to fall over the past decade despite all efforts to increase participation. Many factors have been linked to reduced response, yet relatively few studies have employed multivariate approaches to identify characteristics that differentiate respondents from nonrespondents since it is hard to collect information on the latter. We aimed to assess factors contributing to enrollment of prostate cancer (PCa) patients. We combined data from the North Carolina-Louisiana (LA) PCa Project's LA cohort, with additional sources such as US census tract and LA tumor registry data. We included specific analyses focusing on blacks, a group often identified as hard to enroll in health-related research. The ability to study the effect of Hurricane Katrina, which occurred amidst enrollment, as a potential determinant of nonresponse makes our study unique. Older age (≥ 70) for blacks (OR 0.65) and study phase with respect to Hurricane Katrina for both races (OR 0.59 for blacks, OR 0.48 for whites) were significant predictors of participation with lower odds. Neighborhood poverty for whites (OR 1.53) also was a significant predictor of participation, but with higher odds. Among blacks, residence in Orleans parish was associated with lower odds of participation (OR 0.33) before Katrina. The opposite occurred in whites, with lower odds (OR 0.43) after Katrina. Our results overall underscore the importance of tailoring enrollment approaches to specific target population characteristics to confront the challenges posed by nonresponse. Our results also show that recruitment-related factors may change when outside forces bring major alterations to a population's environment and demographics.


Subject(s)
Adenocarcinoma/epidemiology , Patient Participation/statistics & numerical data , Prostatic Neoplasms/epidemiology , Surveys and Questionnaires , Adenocarcinoma/pathology , Adult , Aged , Bias , Epidemiologic Research Design , Humans , Louisiana/epidemiology , Male , Middle Aged , Neoplasm Invasiveness , North Carolina/epidemiology , Prostatic Neoplasms/pathology , Survival Analysis
9.
J Health Care Poor Underserved ; 27(3): 1592-607, 2016.
Article in English | MEDLINE | ID: mdl-27524787

ABSTRACT

This study aimed to examine whether sociodemographic factors and acculturation affect achievement of selected American Diabetes Association (ADA) nutrition therapy recommendations among Hispanics with diabetes. Cross-sectional data for Hispanics with diabetes in the National Health and Nutrition Examination Survey (NHANES) 2003-2010 were used. Achievements of the ADA recommendation for five nutrition components were examined (i.e., daily intake of saturated fat, cholesterol, sodium, and fiber, and daily servings of alcohol). Acculturation measurement derived from language use, country of birth, and length of residence in the U.S. Logistic regressions were performed. Only 49% of Hispanics with diabetes met three or more recommended criteria. Male gender and younger age (≤45) predicted poor recommendation adherence. More acculturated individuals had around 50% lower odds to achieve saturated fat [OR 0.5, CI 0.2-0.7], fiber [OR 0.5, CI 0.2-0.9], sodium [OR 0.5, CI 0.3-0.9] and cholesterol intake [OR 0.5, CI 0.3-0.8] recommendations than their less acculturated counterparts.


Subject(s)
Acculturation , Alcohol Drinking/ethnology , Diabetes Mellitus/ethnology , Diet , Hispanic or Latino/statistics & numerical data , Adult , Age Factors , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Nutrition Surveys , Self Report , Sex Factors , Socioeconomic Factors , Young Adult
10.
PLoS One ; 10(7): e0132606, 2015.
Article in English | MEDLINE | ID: mdl-26176843

ABSTRACT

BACKGROUND: The prevalence of hypertension is known to differ by racial group in adults in the United States (US), but findings in children are scarce and inconsistent. The objective of this study was to assess the racial differences in pediatric hypertension and to explore whether these differences, if any, can be explained by low birth weight (LBW) and obesity. METHODS: Analyses were performed for participants aged 8-17 years (N = 9,250) included in the 1999-2010 National Health and Nutrition Examination Survey. Multivariate logistic regressions and weighted analysis were carried out considering the complex survey design. RESULTS: Compared to non-Hispanic White youth, the crude prevalence of hypertension was significantly higher in non-Hispanic Blacks (7.1% vs. 5.6%; P = 0.04), but not in Mexican Americans (5.4% vs. 5.6%; P = 0.77). Blacks also had higher rates of LBW (14.6% vs. 5.9%; P <0.001) and obesity (22.9% vs. 15.8%; P <0.001) than Whites. In stratified analysis by age-sex groups, the Black-White difference in hypertension prevalence was only significant in boys aged 13-17 (9.6% vs. 6.6%). After controlling for age, Black boys had a 51% higher odds of having hypertension (Odds ratio = 1.51; 95% confidence interval: 1.03, 3.43; P = 0.04) compared to White youth at ages 13-17. This racial difference persisted with additional adjustment for birth weight (odds ratio (OR) = 2.00; P = 0.02) and for current body mass index (OR = 1.50; P = 0.04). Mexican American youth had no difference in hypertension prevalence as compared to White youth after adjusting for age, sex, birth weight and obesity (Odds ratio = 0.82; P = 0.16) and in age-sex stratified subgroups. CONCLUSIONS: Non-Hispanic Black adolescent boys have a significantly higher hypertension rate than their non-Hispanic White counterparts in the US. This racial difference cannot be explained by LBW and current obesity status within the Black population.


Subject(s)
Hypertension/ethnology , Adolescent , Black or African American , Birth Weight , Body Size , Child , Cross-Sectional Studies , Hispanic or Latino , Humans , Hypertension/epidemiology , Obesity/epidemiology , Obesity/ethnology , Prevalence , United States/epidemiology , White People
11.
Diabetes Educ ; 40(4): 496-506, 2014 07.
Article in English | MEDLINE | ID: mdl-24737884

ABSTRACT

PURPOSE: The purpose of this study is to investigate the racial/ethnic disparities in health-related quality of life (HRQOL) among adults with self-reported diabetes and identify the different risk factors related to HRQOL for specific racial/ethnic groups in the United States. METHODS: National Health and Nutrition Examination Survey (NHANES) 2001-2010 participants (ages 20 years and older) who were self-identified as non-Hispanic white, non-Hispanic black, or Hispanic and with self-reported diabetes were included in the analysis (n = 2594). The Centers for Disease Control and Prevention's HRQOL-4 was used to assess factors associated with HRQOL through multivariate logistic regression models with survey weighting. Stepwise model selection was applied to select the most significant factors for HRQOL in each racial/ethnic group. RESULTS: Hispanic participants were less likely to report 14 or more mentally unhealthy days and activity-limited days compared to non-Hispanic white counterparts, adjusting for age, sex, education, marital status, family poverty-income ratio (PIR), body mass index, smoking status, insurance coverage, and diabetes duration. Current smoking status and obesity were significantly associated with worse HRQOL among whites and blacks. Marital status predicted better HRQOL only among Hispanics. Having insurance coverage predicted better HRQOL among both blacks and Hispanics. Increased family PIR had a favorable association with the 4 HRQOL domains consistently among all races/ethnicities. CONCLUSION: Minimal racial/ethnic disparities in HRQOL were observed among US adults with self-reported diabetes. Support is offered for more individualized health care and communication with patients to target care and interventions that improve health and quality-of-life indicators.


Subject(s)
Diabetes Mellitus/ethnology , Ethnicity/psychology , Health Status Disparities , Quality of Life , Racial Groups/psychology , Adult , Black or African American/psychology , Aged , Diabetes Mellitus/psychology , Diagnostic Self Evaluation , Female , Hispanic or Latino/psychology , Humans , Male , Middle Aged , Nutrition Surveys , United States , White People/psychology , Young Adult
12.
Spat Spatiotemporal Epidemiol ; 3(2): 121-8, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22682438

ABSTRACT

Many previous studies have suggested a link between alcohol outlets and assaultive violence rates. In 1997 the City of New Orleans adopted a series of policies, e.g., increased license fee, additional enforcement staff, and expanded powers for the alcohol license board. The policies were specifically enacted to address the proliferation of problem alcohol outlets believed to be the source of a variety of social problems including assaultive violence. In this research, we evaluate the impact of a city level policy in New Orleans to address the problem alcohol outlets and their influence on assaultive violence. The spatial association between rates of assaultive violence at the census tract level (n=170) over a ten year period raises a challenge in statistical analysis. To meet this challenge we developed a hierarchical change-point model that controls for important covariates of assaultive violence and accounts for unexplained spatial and temporal variability. While our model is somewhat complex, its hierarchical Bayesian analysis is accessible via the WinBUGS software program. Keeping other effects fixed, the implementation of the new city level policy was associated with a decrease in the positive association between census tract level rates of assaultive violence and alcohol outlet density. Comparing several candidate change-point models using the DIC criterion, the positive association began decreasing the year of the policy implementation. The magnitude of the association continued to decrease for roughly two years and then stabilized. We also created maps of the fitted assaultive violence rates in New Orleans, as well as spatial residual maps which, together with Moran's I's, suggest that the spatial variation of the data is well accounted for by our model. We reach the conclusion that the implementation of the policy is associated with a significant decrease in the positive relationship between assaultive violence and the off-sale alcohol outlet density.


Subject(s)
Alcoholic Beverages/supply & distribution , Commerce/legislation & jurisprudence , Models, Theoretical , Residence Characteristics/statistics & numerical data , Spatio-Temporal Analysis , Violence/trends , Bayes Theorem , Humans , Licensure/legislation & jurisprudence , Longitudinal Studies , New Orleans , Public Policy , Socioeconomic Factors , Software , Urban Population , Violence/prevention & control , Violence/statistics & numerical data
13.
Alcohol Clin Exp Res ; 36(9): 1608-13, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22432502

ABSTRACT

BACKGROUND: A number of college presidents have endorsed the Amethyst Initiative, a call to consider lowering the minimum legal drinking age (MLDA). Our objective is to forecast the effect of the Amethyst Initiative on college drinking. METHODS: A system model of college drinking simulates MLDA changes through (i) a decrease in heavy episodic drinking (HED) because of the lower likelihood of students drinking in unsupervised settings where they model irresponsible drinking (misperception), and (ii) an increase in overall drinking among currently underage students because of increased social availability of alcohol (wetness). RESULTS: For the proportion of HEDs on campus, effects of large decreases in misperception of responsible drinking behavior were more than offset by modest increases in wetness. CONCLUSIONS: For the effect of lowering the MLDA, it appears that increases in social availability of alcohol have a stronger impact on drinking behavior than decreases in misperceptions.


Subject(s)
Alcohol Drinking/epidemiology , Alcohol Drinking/legislation & jurisprudence , Adolescent , Alcohol Drinking/psychology , Algorithms , Computer Simulation , Culture , Forecasting , Humans , Interpersonal Relations , Models, Organizational , Risk Assessment , Social Environment , Students , Young Adult
14.
J La State Med Soc ; 163(1): 44-7, 2011.
Article in English | MEDLINE | ID: mdl-21675006

ABSTRACT

OBJECTIVES: We sought to determine if low birth weight (LBW) occurs more frequently in African American children with type 2 diabetes (T2D), and if patients with LBW differ metabolically. STUDY DESIGN: We collected birth weight, anthropometric and metabolic data from African American children with T2D born in New Orleans from clinic charts. Comparable birth weight data from all African American infants born in New Orleans were obtained from Louisiana state vital statistics. RESULTS: In African American patients with T2D, 14.3% had LBW compared to 13.9% in the reference population (z = 0.997, p = 0.33). There was no difference between LBW and non-LBW patients with regard to body mass index (BMI) at diagnosis, presenting insulin, c-peptide, glucose levels, or HbA1c one year post diagnosis. CONCLUSIONS: African American children with T2D were not enriched with LBW individuals. LBW patients were not anthropometrically or metabolically different from non-LBW T2D patients. Thus prenatal factors may not be the driving force in the development of T2D in African American children.


Subject(s)
Black or African American , Diabetes Mellitus, Type 2/epidemiology , Infant, Low Birth Weight , Adolescent , Anthropometry , Female , Humans , Infant, Newborn , Male , New Orleans/epidemiology , Retrospective Studies , Risk Factors
15.
J Stud Alcohol Drugs ; 72(2): 232-9, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21388596

ABSTRACT

OBJECTIVE: Evaluations of social norms marketing campaigns to reduce college student drinking have produced conflicting results. This study examines whether the effectiveness of such campaigns may be moderated by on-premise alcohol outlet density in the surrounding community. METHOD: Multilevel analyses were conducted of student survey responses (N= 19,838) from 32 U.S. colleges that took part in one of two 4-year randomized, controlled trials completed for the Social Norms Marketing Research Project (SNMRP). In the models, students by year were nested within treatment (n = 16) and control group (n = 16) campuses, which were characterized by the on-premise outlet density in their surrounding community. The moderating effect of outlet density was introduced into the models as an interaction between the treatment effect (i.e., the effect of the social norms marketing campaigns over time) and outlet density. The models were also stratified by campus alcohol outlet density (high vs. low) to examine the effect of the intervention in each type of setting. RESULTS: There was a significant interaction between the treatment effect and on-premise alcohol outlet density for one of the drinking outcomes targeted by the SNMRP intervention, the number of drinks when partying, and marginal evidence of interaction effects for two other outcomes, maximum recent consumption and a composite drinking scale. In stratified analyses, an intervention effect was observed for three of the four outcomes among students from campuses with lower on-premise alcohol outlet density, whereas no intervention effect was observed among students from campuses with higher on-premise alcohol outlet density. CONCLUSIONS: The findings suggest that the campus alcohol environment moderates the effect of social norms marketing interventions. Social norms marketing intervention may be less effective on campuses with higher densities of on-sale alcohol outlets.


Subject(s)
Alcohol Drinking/prevention & control , Marketing , Social Environment , Students/statistics & numerical data , Universities/statistics & numerical data , Alcohol Drinking/pathology , Data Collection , Ethanol , Humans , Social Marketing , Students/psychology
16.
J Epidemiol Community Health ; 65(8): 688-95, 2011 Aug.
Article in English | MEDLINE | ID: mdl-20508007

ABSTRACT

BACKGROUND: Given the growing availability of multilevel data from national surveys, researchers interested in contextual effects may find themselves with a small number of individuals per group. Although there is a growing body of literature on sample size in multilevel modelling, few have explored the impact of group sizes of less than five. METHODS: In a simulated analysis of real data, the impact of a group size of less than five was examined on both a continuous and dichotomous outcome in a simple two-level multilevel model. Models with group sizes one to five were compared with models with complete data. Four different linear and logistic models were examined: empty models; models with a group-level covariate; models with an individual-level covariate and models with an aggregated group-level covariate. The study evaluated further whether the impact of small group size differed depending on the total number of groups. RESULTS: When the number of groups was large (N=459), neither fixed nor random components were affected by small group size, even when 90% of tracts had only one individual per tract and even when an aggregated group-level covariate was examined. As the number of groups decreased, the SE estimates of both fixed and random effects were inflated. Furthermore, group-level variance estimates were more affected than were fixed components. CONCLUSIONS: Datasets in which there is a small to moderate number of groups, with the majority of very small group size (n<5), size may fail to find or even consider a group-level effect when one may exist and also may be underpowered to detect fixed effects.


Subject(s)
Models, Theoretical , Residence Characteristics , Sample Size , Body Mass Index , Data Collection , Databases as Topic , Female , Humans , Male , Research Design , United States
17.
J Stud Alcohol Drugs ; 72(1): 15-23, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21138707

ABSTRACT

OBJECTIVE: This article extends the compartmental model previously developed by Scribner et al. in the context of college drinking to a mathematical model of the consequences of lowering the legal drinking age. METHOD: Using data available from 32 U.S. campuses, the analyses separate underage and legal age drinking groups into an eight-compartment model with different alcohol availability (wetness) for the underage and legal age groups. The model evaluates the likelihood that underage students will incorrectly perceive normative drinking levels to be higher than they actually are (i.e., misperception) and adjust their drinking accordingly by varying the interaction between underage students in social and heavy episodic drinking compartments. RESULTS: The results evaluate the total heavy episodic drinker population and its dependence on the difference in misperception, as well as its dependence on underage wetness, legal age wetness, and drinking age. CONCLUSIONS: Results suggest that an unrealistically extreme combination of high wetness and low enforcement would be needed for the policies related to lowering the drinking age to be effective.


Subject(s)
Alcohol Drinking/epidemiology , Alcohol Drinking/legislation & jurisprudence , Alcoholic Beverages , Universities/statistics & numerical data , Alcohol Drinking/psychology , Alcoholism/epidemiology , Alcoholism/psychology , Humans , Models, Theoretical , Social Environment , Students , Surveys and Questionnaires
18.
J Environ Public Health ; 2010: 759645, 2010.
Article in English | MEDLINE | ID: mdl-20300547

ABSTRACT

To investigate potential links between environmental exposure to petrochemical plant emissions and lung cancer, a population-based case-control study (LMRICS) was conducted in eleven Louisiana parishes bordering the Mississippi River. Cases and age, gender, and race-matched controls were interviewed regarding potential risk factors. Residential history was geocoded to provide indices of long-term proximity to industrial sites. Cases were more likely to have lived near a petrochemical site. Models adjusted for other risk factors, however, showed small or no association with lung cancer (odds ratio for residence within a half-mile of a site = 1.10, 95% confidence interval 0.58-2.08). While associations were strongest for exposures exceeding 15 years, none approached statistical significance and there was no clear dose-response across exposure duration, distance categories, or when sites were grouped according to carcinogenicity rating of chemical releases. Residential proximity to petrochemical plants along the lower Mississippi thus showed no significant association with lung cancer.


Subject(s)
Air Pollutants/adverse effects , Environmental Exposure/adverse effects , Extraction and Processing Industry , Hydrocarbons/adverse effects , Lung Neoplasms/chemically induced , Petroleum/adverse effects , Adult , Aged , Carcinogens, Environmental/adverse effects , Case-Control Studies , Environmental Exposure/statistics & numerical data , Female , Humans , Logistic Models , Louisiana , Lung Neoplasms/epidemiology , Male , Middle Aged , Odds Ratio , Registries , Residence Characteristics , Risk Factors , Surveys and Questionnaires , Time Factors
19.
J Stud Alcohol Drugs ; 71(2): 184-91, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20230715

ABSTRACT

OBJECTIVE: The purpose of this study was to assess the relationships among campus violence, student drinking levels, and the physical availability of alcohol at off-campus outlets in a multisite design. METHOD: An ecological analysis of on-campus violence was conducted at 32 U.S. colleges. Dependent variables included campus-reported rates of rape, robbery, assault, and burglary obtained from a U.S. Department of Education online database for the years 2000-2004. Measures of student alcohol use and demographics were obtained from student surveys conducted for the Social Norms Marketing Research Project from 2000 to 2004. Measures of alcohol-outlet density within 3 miles of each campus were obtained from state alcohol-licensing authorities for 2004. RESULTS: Both on- and off-premise alcohol-outlet densities were associated with the campus rape-offense rate but not with the assault or robbery rates. Student drinking level was associated with both campus rape and assault rates but not with the campus robbery rate. The apparent effect of on-premise outlet density on campus rape-offense rates was reduced when student drinking level was included in the model, suggesting that the effect of on-premise outlet density may be mediated by student drinking level. Separate analyses revealed a similar mediational role for off-premise outlet density. CONCLUSIONS: These findings demonstrate that there is a campus-level association between sexual violence and the campus-community alcohol environment.


Subject(s)
Alcohol Drinking/epidemiology , Alcoholic Beverages/supply & distribution , Commerce/statistics & numerical data , Violence/statistics & numerical data , Crime/statistics & numerical data , Data Collection , Female , Humans , Male , Rape/statistics & numerical data , Students/statistics & numerical data , United States , Universities
20.
Alcohol Res Health ; 33(3): 179-83, 2010.
Article in English | MEDLINE | ID: mdl-23584059

ABSTRACT

The study of individual risk factors is inadequate to address the current public health challenges associated with HIV/AIDS. Rather, an ecological epidemiological study of HIV/AIDS is needed to address these challenges. A socioecological framework has been proposed for HIV/AIDS, including influences at the individual level, the interpersonal level, the neighborhood level, and the societal level. This framework provides the basis for a conceptual model with specific risk factors at each of these levels and cross-level associations. The nature of the associations also is important, in particular the assumption that the neighborhood alcohol environment exerts its effect on HIV risk through both direct and indirect pathways.


Subject(s)
Acquired Immunodeficiency Syndrome/epidemiology , Alcoholism/epidemiology , Social Environment , Acquired Immunodeficiency Syndrome/diagnosis , Acquired Immunodeficiency Syndrome/prevention & control , Alcohol Drinking/epidemiology , Alcohol Drinking/prevention & control , Alcoholism/diagnosis , Alcoholism/prevention & control , Animals , HIV Infections/diagnosis , HIV Infections/epidemiology , HIV Infections/prevention & control , Humans , Risk Factors
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