Advancing the Social Epidemiology Mission of the American Journal of Epidemiology.

Social epidemiology is concerned with how social forces influence population health. Rather than focusing on a single disease (as in cancer or cardiovascular epidemiology) or a single type of exposure (e.g., nutritional epidemiology), social epidemiology encompasses all the social and economic determinants of health, both historical and contemporary. These include features of social and physical environments, the network of relationships in a society, and the institutions, politics, policies, norms and cultures that shape all of these forces. This commentary presents the perspective of several editors at the Journal with expertise in social epidemiology. We articulate our thinking to encourage submissions to the Journal that: 1) expand knowledge of emerging and underresearched social determinants of population health; 2) advance new empirical evidence on the determinants of health inequities and solutions to advance health equity; 3) generate evidence to inform the translation of research on social determinants of health into public health impact; 4) contribute to innovation in methods to improve the rigor and relevance of social epidemiology; and 5) encourage critical self-reflection on the direction, challenges, successes, and failures of the field.

Perceptions of a food benefit programme that includes financial incentives for the purchase of fruits and vegetables and restrictions on the purchase of foods high in added sugar.

OBJECTIVE: To report perspectives of participants in a food benefit programme that includes foods high in added sugar (FAS) restrictions and FAS restrictions paired with fruits and vegetables (F/V) incentives. DESIGN: Randomised experimental trial in which participant perspectives were an exploratory study outcome. SETTING: Participants were randomised into one of three Supplemental Nutrition Assistance Program (SNAP)-like food benefit programme groups: (1) restriction: not allowed to buy FAS with benefits; (2) restriction paired with incentive: not allowed to buy FAS with benefits and 30 % financial incentive on eligible F/V purchased using benefits; or (3) control: same food purchasing rules as SNAP. Participants were asked questions to assess programme satisfaction. PARTICIPANTS: Adults in the Minneapolis-St. Paul, MN metropolitan area, eligible for but not currently participating in SNAP who completed baseline and follow-up study measures (n 254). RESULTS: Among remaining households in each group, most found the programme helpful in buying nutritious foods (88·2 %-95·7 %) and were satisfied with the programme (89·1 %-93·0 %). Sensitivity analysis results indicate that reported helpfulness and satisfaction with the programme may in some instances be lower among the restriction and the restrictions paired with incentive groups in comparison to the control group. CONCLUSIONS: A food benefit programme that includes restriction on purchase of FAS or restriction paired with a financial incentive for F/V purchases may be acceptable to most SNAP-eligible households with children.

Neighborhood Socioeconomic Status and Identification of Patients With CKD Using Electronic Health Records.

RATIONALE & OBJECTIVE: Screening for chronic kidney disease (CKD) is recommended for patients with diabetes and hypertension as stated by the respective professional societies. However, CKD, a silent disease usually detected at later stages, is associated with low socioeconomic status (SES). We assessed whether adding census tract SES status to the standard screening approach improves our ability to identify patients with CKD. STUDY DESIGN: Screening test analysis. SETTINGS & PARTICIPANTS: Electronic health records (EHR) of 256,162 patients seen at a health care system in the 7-county Minneapolis/St. Paul area and linked census tract data. EXPOSURE: The first quartile of census tract SES (median value of owner-occupied housing units <$165,200; average household income <$35,935; percentage of residents >25 years of age with a bachelor's degree or higher <20.4%), hypertension, and diabetes. OUTCOMES: CKD (eGFR <60 mL/min/1.73 m2, or urinary albumin-creatinine ratio >30mg/g, or urinary protein-creatinine ratio >150mg/g, or urinary analysis [albuminuria] >30 mg/d). ANALYTICAL APPROACH: Sensitivity, specificity, and number needed to screen (NNS) to detect CKD if we screened patients who had hypertension and/or diabetes and/or who lived in low-SES tracts (belonging to the first quartile of any of the 3 measures of tract SES) versus the standard approach. RESULTS: CKD was prevalent in 13% of our cohort. Sensitivity, specificity, and NNS of detecting CKD after adding tract SES to the screening approach were 67% (95% CI, 66.2%-67.2%), 61% (95% CI, 61.1%-61.5%), and 5, respectively. With the standard approach, sensitivity of detecting CKD was 60% (95% CI, 59.4%-60.4%), specificity was 73% (95% CI, 72.4%-72.7%), and NNS was 4. LIMITATIONS: One health care system and selection bias. CONCLUSIONS: Leveraging patients' addresses from the EHR and adding tract-level SES to the standard screening approach modestly increases the sensitivity of detecting patients with CKD at a cost of decreased specificity. Identifying further factors that improve CKD detection at an early stage are needed to slow the progression of CKD and prevent cardiovascular complications.

Within- and Between-Household Variation in Food Expenditures Among Low-Income Households Using a Novel Simple Annotated Receipt Method.

Background: Household food purchasing behavior has gained interest as an intervention to improve nutrition and nutrition-associated outcomes. However, evaluating food expenditures is challenging in epidemiological studies. Assessment methods that are both valid and feasible for use among diverse, low-income populations are needed. We therefore developed a novel simple annotated receipt method to assess household food purchasing. First, we describe and evaluate the extent to which the method captures food purchasing information. We then evaluate within- and between-household variation in weekly food purchasing to determine sample sizes and the number of weeks of data needed to measure household food purchasing with adequate precision. Methods: Four weeks of food purchase receipt data were collected from 260 low-income households in the Minneapolis-St. Paul metropolitan area. The proportion of receipt line items that could not be coded into one of 11 food categories (unidentified) was calculated, and a zero-inflated negative binomial regression was used to evaluate the association between unidentified receipt items and participant characteristics and store type. Within- and between-household coefficients of variation were calculated for total food expenditures and several food categories. Results: A low proportion of receipt line items (1.6%) could not be coded into a food category and the incidence of unidentified items did not appreciably vary by participant characteristics. Weekly expenditures on foods high in added sugar had higher within- and between-household coefficients of variation than weekly fruit and vegetable expenditures. To estimate mean weekly food expenditures within 20% of the group's usual ("true") expenditures, 72 households were required. Nine weeks of data were required to achieve an r = 0.90 between observed and usual weekly food expenditures. Conclusions: The simple annotated receipt method may be a feasible tool for use in assessing food expenditures of low-income, diverse populations. Within- and between-household coefficients of variation suggest that the number of weeks of data or group sizes required to precisely estimate usual household expenditures is higher for foods high in added sugar compared to fruits and vegetables.

Participant Satisfaction with a Food Benefit Program with Restrictions and Incentives.

BACKGROUND: Policy makers are considering changes to the Supplemental Nutrition Assistance Program (SNAP). Proposed changes include financially incentivizing the purchase of healthier foods and prohibiting the use of funds for purchasing foods high in added sugars. SNAP participant perspectives may be useful in understanding the consequences of these proposed changes. OBJECTIVE: To determine whether food restrictions and/or incentives are acceptable to food benefit program participants. DESIGN: Data were collected as part of an experimental trial in which lower-income adults were randomly assigned to one of four financial food benefit conditions: (1) Incentive: 30% financial incentive on eligible fruits and vegetables purchased using food benefits; (2) Restriction: not allowed to buy sugar-sweetened beverages, sweet baked goods, or candies with food benefits; (3) Incentive plus Restriction; or (4) Control: no incentive/restriction. Participants completed closed- and open-ended questions about their perceptions on completion of the 12-week program. PARTICIPANTS/SETTING: Adults eligible or nearly eligible for SNAP were recruited between 2013 and 2015 by means of events or flyers in the Minneapolis/St Paul, MN, metropolitan area. Of the 279 individuals who completed baseline measures, 265 completed follow-up measures and are included in these analyses. STATISTICAL ANALYSIS: χ2 analyses were conducted to assess differences in program satisfaction. Responses to open-ended questions were qualitatively analyzed using principles of content analysis. RESULTS: There were no statistically significant or meaningful differences between experimental groups in satisfaction with the program elements evaluated in the study. Most participants in all conditions found the food program helpful in buying nutritious foods (94.1% to 98.5%) and in buying the kinds of foods they wanted (85.9% to 95.6%). Qualitative data suggested that most were supportive of restrictions, although a few were dissatisfied. Participants were uniformly supportive of incentives. CONCLUSIONS: Findings suggest a food benefit program that includes incentives for purchasing fruits and vegetables and/or restrictions on the use of program funds for purchasing foods high in added sugars appears to be acceptable to most participants.

Effects of Subsidies and Prohibitions on Nutrition in a Food Benefit Program: A Randomized Clinical Trial.

Importance: Strategies to improve the nutritional status of those participating in the Supplemental Nutrition Assistance Program (SNAP) are of interest to policymakers. Objective: To evaluate whether the proposed policy of incentivizing the purchase of fruits and vegetables and prohibiting the purchase of less nutritious foods in a food benefit program improves the nutritional quality of participants' diets. Design, Setting, and Participants: Lower income participants (n = 279) not currently enrolled in SNAP were randomized to 1 of 4 experimental financial food benefit conditions: (1) incentive (30% financial incentive for fruits and vegetables purchased using food benefits); (2) restriction (not allowed to buy sugar sweetened beverages, sweet baked goods, or candies with food benefits); (3) incentive plus restriction (30% financial incentive on fruits and vegetables and restriction of purchase of sugar sweetened beverages, sweet baked goods, or candy with food benefits); or (4) control (no incentive or restrictions on foods purchased with food benefits). Participants in all conditions were given a study-specific debit card where funds were added every 4 weeks for a 12-week period. Outcome measures were collected at baseline and in the final 4 weeks of the experimental period. Main Outcomes and Measures: Primary outcomes (from 24-hour dietary recalls) included intake of energy, discretionary calories, and overall diet quality. Results: A number of favorable changes were observed in the incentive plus restriction condition that were significantly different from changes in the control condition. These included (1) reduced intake of energy (-96 kcal/d, standard error [SE], 59.9); (2) reduced intake of discretionary calories (-64 kcal/d, SE 26.3); (3) reduced intake of sugar sweetened beverages, sweet baked goods, and candies (-0.6 servings/d, SE 0.2); (4) increased intake of solid fruit (0.2 servings/d, SE 0.1); and (5) improved Healthy Eating Index score (4.1 points, SE 1.4). Fewer improvements were observed in the incentive only and restriction only arms. Conclusions and Relevance: A food benefit program that pairs incentives for purchasing more fruits and vegetables with restrictions on the purchase of less nutritious foods may reduce energy intake and improve the nutritional quality of the diet of participants compared with a program that does not include incentives or restrictions. Clinical Trial Registration: clinicaltrials.gov Identifier: NCT02643576.

Examining the Impact of Maternal Health, Race, and Socioeconomic Status on Daughter's Self-Rated Health Over Three Decades.

This study examines the role of mother's health and socioeconomic status on daughter's self-rated health using data spanning three decades from the National Longitudinal Surveys of Mature Women and Young Women (N = 1,848 matched mother-daughter pairs; 1,201 White and 647 African American). Using nested growth curve models, we investigated whether mother's self-rated health affected the daughter's self-rated health and whether socioeconomic status mediated this relationship. Mother's health significantly influenced daughters' self-rated health, but the findings were mediated by mother's socioeconomic status. African American daughters reported lower self-rated health and experienced more decline over time compared with White daughters, accounting for mother's and daughter's covariates. Our findings reveal maternal health and resources as a significant predictor of daughters' self-rated health and confirm the role of socioeconomic status and racial disparities over time.

Using administrative health care system records to recruit a community-based sample for population research.

PURPOSE: Epidemiologists often seek a representative sample of particular persons from geographically bounded areas. However, it has become increasingly difficult to identify a sample frame that truly represents the underlying target population. We assessed the degree to which a clinic-based sample represents a target community. METHODS: Our sample frame is from a large health care provider from the Minneapolis-Saint Paul, Minnesota, metropolitan area. We used U.S. Census data to examine the sociodemographic and geospatial distribution of the sampling frame and among those who did and did not respond. RESULTS: Our study's overall response rate was 57%. The most impoverished areas of the target population were under-represented in our sample frame, but this under-representation was similar for both respondents and nonrespondents. In addition, our sampled population was slightly older compared to the target population. Using ecological-level census-derived markers of sociodemographic characteristics, members of the sample frame were similar to that of the target population except for being somewhat more highly educated. However, the distributions of available individual-level data such as race and education were different between respondents and the target population. CONCLUSIONS: Although the use of health care administrative records for identifying a sampling frame that represents a target population has limitations, our findings suggest that this method had strengths. More comparisons of methods for identifying and recruiting target populations are needed.

Twenty Years of Neighborhood Effect Research: An Assessment.

This paper reviews the magnitude and empirical findings of social epidemiological neighborhood effects research. An electronic keyword literature search identified 1369 empirical and methodological neighborhood effects papers published in 112 relevant journals between 1990 and 2014. Analyses of temporal trends were conducted by focus, journal type (e.g., epidemiology, public health, or social science), and specific epidemiologic journal. Select papers were then critically reviewed. Results show an ever-increasing number of papers published, notably since the year 2000, with the majority published in public health journals. The variety of health outcomes analyzed is extensive, ranging from infectious disease to obesity to criminal behavior. Papers relying on data from experimental designs are thought to yield the most credible results, but such studies are few and findings are inconsistent. Papers relying on data from observational designs and multilevel models typically show small statistically significant effects, but most fail to appreciate fundamental identification problems. Ultimately, of the 1170 empirically focused neighborhood effects papers published in the last 24 years, only a handful have clearly advanced our understanding of the phenomena. The independent impact of neighborhood contexts on health remains unclear. It is time to expand the social epidemiological imagination.

Estimation of geographic variation in human papillomavirus vaccine uptake in men and women: an online survey using facebook recruitment.

BACKGROUND: Federally funded surveys of human papillomavirus (HPV) vaccine uptake are important for pinpointing geographically based health disparities. Although national and state level data are available, local (ie, county and postal code level) data are not due to small sample sizes, confidentiality concerns, and cost. Local level HPV vaccine uptake data may be feasible to obtain by targeting specific geographic areas through social media advertising and recruitment strategies, in combination with online surveys. OBJECTIVE: Our goal was to use Facebook-based recruitment and online surveys to estimate local variation in HPV vaccine uptake among young men and women in Minnesota. METHODS: From November 2012 to January 2013, men and women were recruited via a targeted Facebook advertisement campaign to complete an online survey about HPV vaccination practices. The Facebook advertisements were targeted to recruit men and women by location (25 mile radius of Minneapolis, Minnesota, United States), age (18-30 years), and language (English). RESULTS: Of the 2079 men and women who responded to the Facebook advertisements and visited the study website, 1003 (48.2%) enrolled in the study and completed the survey. The average advertising cost per completed survey was US $1.36. Among those who reported their postal code, 90.6% (881/972) of the participants lived within the previously defined geographic study area. Receipt of 1 dose or more of HPV vaccine was reported by 65.6% women (351/535), and 13.0% (45/347) of men. These results differ from previously reported Minnesota state level estimates (53.8% for young women and 20.8% for young men) and from national estimates (34.5% for women and 2.3% for men). CONCLUSIONS: This study shows that recruiting a representative sample of young men and women based on county and postal code location to complete a survey on HPV vaccination uptake via the Internet is a cost-effective and feasible strategy. This study also highlights the need for local estimates to assess the variation in HPV vaccine uptake, as these estimates differ considerably from those obtained using survey data that are aggregated to the state or federal level.

Invited commentary: repeated measures, selection bias, and effect identification in neighborhood effect studies.

Research on neighborhood effects faces enormous methodological challenges, with selection bias being near the top of the list. In this issue of the Journal (Am J Epidemiol. 2014;180(8):776-784), Professor Jokela addresses this issue with novel repeated measures data and models that decompose putative effects into those within and between persons. His contribution shows that within-person neighborhood effects are quite modest and that there is evidence of selection bias between persons. Like all research, the work rests on assumptions. Unfortunately, such assumptions are difficult to substantiate or validate in this context. A consequentialist epidemiologic perspective compels further innovation and a larger social epidemiologic imagination.

Food prices and food shopping decisions of black women.

Identifying food pricing strategies to encourage purchases of lower-calorie food products may be particularly important for black Americans. Black children and adults have higher than average obesity prevalence and disproportionate exposure to food marketing environments in which high calorie foods are readily available and heavily promoted. The main objective of this study was to characterize effects of price on food purchases of black female household shoppers in conjunction with other key decision attributes (calorie content/healthfulness, package size, and convenience). Factorial discrete choice experiments were conducted with 65 low- and middle-/higher-income black women. The within-subject study design assessed responses to hypothetical scenarios for purchasing frozen vegetables, bread, chips, soda, fruit drinks, chicken, and cheese. Linear models were used to estimate the effects of price, calorie level (or healthfulness for bread), package size, and convenience on the propensity to purchase items. Moderating effects of demographic and personal characteristics were assessed. Compared with a price that was 35% lower, the regular price was associated with a lesser propensity to purchase foods in all categories (ß = -0.33 to -0.82 points on a 1 to 5 scale). Other attributes, primarily calorie content/healthfulness, were more influential than price for four of seven foods. The moderating variable most often associated with propensity to pay the regular versus lower price was the reported use of nutrition labels. Price reductions alone may increase purchases of certain lower-calorie or more healthful foods by black female shoppers. In other cases, effects may depend on combining price changes with nutrition education or improvements in other valued attributes.

Invited commentary: Paths and pathologies of social epidemiology.

The article by professors Galea and Link in this issue of the Journal (Am J Epidemiol. 2013;178(6):843-849) is an important contribution to the field of social epidemiology. Their 6 paths provide ample fodder for reflection, debate, and advancement. Although I agree with the thrust and spirit of their recommendations, I argue that if social epidemiology is to advance and become not just more popular but also more useful, we social epidemiologists need to first address our disciplinary pathologies. Among other things, we must embrace macro-to-micro transitions, understand and act on the principles of effect identification, conduct many more experiments, and train students to be not researchers but scientists.

Accelerometer test-retest reliability by data processing algorithms: results from the Twin Cities Walking Study.

BACKGROUND: The purpose of this study was to determine 1) the test-retest reliability of adult accelerometer-measured physical activity, and 2) how data processing decisions affect physical activity levels and test-retest reliability. METHODS: 143 people wore the ActiGraph accelerometer for 2 7-day periods, 1 to 4 weeks apart. Five algorithms, varying nonwear criteria (20 vs. 60 min of 0 counts) and minimum wear requirements (6 vs. 10 hrs/day for ≥ 4 days) and a separate algorithm requiring ≥ 3 counts per min and ≥ 2 hours per day, were used to process the accelerometer data. RESULTS: Processing the accelerometer data with different algorithms resulted in different levels of counts per day, sedentary, and moderate-to-vigorous physical activity. Reliability correlations were very good to excellent (ICC = 0.70-0.90) for almost all algorithms and there were no significant differences between physical activity measures at Time 1 and Time 2. CONCLUSIONS: This paper presents the first assessment of test-retest reliability of the Actigraph over separate administrations in free-living subjects. The ActiGraph was highly reliable in measuring activity over a 7-day period in natural settings but data were sensitive to the algorithms used to process them.

Effects of socioeconomic and racial residential segregation on preterm birth: a cautionary tale of structural confounding.

Confounding associated with social stratification or other selection processes has been called structural confounding. In the presence of structural confounding, certain covariate strata will contain only subjects who could never be exposed, a violation of the positivity or experimental treatment effect assumption. Thus, structural confounding can prohibit the exchangeability necessary for meaningful causal contrasts across levels of exposure. The authors explored the presence and magnitude of structural confounding by estimating the independent effects of neighborhood deprivation and neighborhood racial composition (segregation) on rates of preterm birth in Wake and Durham counties, North Carolina (1999-2001). Tabular analyses and random-intercept fixed-slope multilevel logistic models portrayed different structural realities in these counties. The multilevel modeling results suggested some nonsignificant effect of residence in tracts with high levels of socioeconomic deprivation or racial residential segregation on adjusted odds of preterm birth for white and black women living in these counties, and the confidence limit ratios indicated fairly consistent levels of precision around the estimates. The results of the tabular analysis, however, suggested that many of these regression modeling findings were off-support and based on no actual data. The implications for statistical and public health inference, in the presence of no data, are considered.

Providing calorie information on fast-food restaurant menu boards: consumer views.

PURPOSE: To gather consumer input about approaches to providing energy composition information for foods on fast-food restaurant menus. DESIGN: We asked a subset of individuals (n = 150) in an experimental study about the influence of nutrition labeling on fast-food meal choices to evaluate calorie information on mock fast-food menus in various formats. SETTING: Three community sites in the Minneapolis-St. Paul, Minnesota, metropolitan area. SUBJECTS: Adolescents and adults who ate fast food at least once per week were recruited. MEASURES: Via a series of open- and close-ended questions, participants gave feedback about several formats for providing energy composition information for foods on fast-food restaurant menus. ANALYSIS: Means and frequencies were calculated, and chi2 tests were conducted. RESULTS: When asked to compare a menu that provided calorie information for each menu item with a menu that provided the number of minutes of running that would be required to burn the calories contained in each menu item, 71.0% of participants preferred the calorie information over the physical activity information. Participants also compared two approaches to providing caloric reference information on the menu (average daily calorie needs per day vs. per meal), and 61.3% preferred the calorie needs-per-meal format. CONCLUSION: Our results may be useful in designing approaches to providing energy composition information for foods on fast-food restaurant menus.

Area-level variation in adolescent smoking.

INTRODUCTION: The purpose of this study is to 1) examine the variability in the prevalence of adolescent smoking in 60 geographic areas of Minnesota and 2) assess how variability in area-level smoking prevalence is associated with area-level sociodemographic characteristics. METHODS: Smoking data were collected from 3,636 adolescents residing in 60 areas of the state of Minnesota. Area-level characteristics were obtained from the 2000 US Census. Coefficient of variation was calculated to assess variability in smoking prevalence across areas, and mean smoking prevalence was compared above and below the median for each area-level characteristic. RESULTS: Substantial variation was found in adolescent smoking prevalence rates. Across the 60 areas, the percentage of adolescents that ever smoked varied from 13% to 53%, and the percentage of adolescents that smoked in the past 30 days ranged from 3% to 19%. Mean lifetime smoking prevalence was higher in areas with a higher percentage of residents with less than a high school education, a lower percentage of residents living in an urban area, lower median housing value and a lower median household income, a higher percentage of residents aged 16 years or older who were unemployed, and a higher percentage of residents with an income-to-poverty ratio less than 1.5. Similar results were found for past 30-day smoking prevalence among girls; however, no area-level characteristics were significantly associated with past 30-day smoking prevalence among boys. CONCLUSION: Results suggest that area-level characteristics may play an important role in adolescent smoking, particularly for girls.

Effects of calorie labeling and value size pricing on fast food meal choices: results from an experimental trial.

BACKGROUND: Although point-of-purchase calorie labeling at restaurants has been proposed as a strategy for improving consumer food choices, a limited number of studies have evaluated this approach. Likewise, little research has been conducted to evaluate the influence of value size pricing on restaurant meal choices. METHODS: To examine the effect of point-of-purchase calorie information and value size pricing on fast food meal choices a randomized 2 x 2 factorial experiment was conducted in which participants ordered a fast food meal from one of four menus that varied with respect to whether calorie information was provided and whether value size pricing was used. Study participants included 594 adolescents and adults who regularly ate at fast food restaurants. Study staff recorded the foods ordered and consumed by each participant. Participants also completed surveys to assess attitudes, beliefs and practices related to fast food and nutrition. RESULTS: No significant differences in the energy composition of meals ordered or eaten were found between menu conditions. The average energy content of meals ordered by those randomized to a menu that included calorie information and did not include value size pricing was 842 kcals compared with 827 kcals for those who ordered their meal from a menu that did not include calorie information but had value size pricing (control menu). Results were similar in most analyses conducted stratified by factors such as age, race and education level. CONCLUSION: Additional research is needed to better evaluate the effects of calorie labeling and value size pricing on fast food meal choices. Studies in which participants are repeatedly exposed to these factors are needed since long term exposure may be required for behavior change.

Why eat at fast-food restaurants: reported reasons among frequent consumers.

A convenience sample of adolescents and adults who regularly eat at fast-food restaurants were recruited to participate in an experimental trial to examine the effect of nutrition labeling on meal choices. As part of this study, participants were asked to indicate how strongly they agreed or disagreed with 11 statements to assess reasons for eating at fast-food restaurants. Logistic regression was conducted to examine whether responses differed by demographic factors. The most frequently reported reasons for eating at fast-food restaurants were: fast food is quick (92%), restaurants are easy to get to (80%), and food tastes good (69%). The least frequently reported reasons were: eating fast food is a way of socializing with family and friends (33%), restaurants have nutritious foods to offer (21%), and restaurants are fun and entertaining (12%). Some differences were found with respect to the demographic factors examined. It appears that in order to reduce fast-food consumption, food and nutrition professionals need to identify alternative quick and convenient food sources. As motivation for eating at fast-food restaurants appears to differ somewhat by age, sex, education, employment status, and household size, tailored interventions could be considered.

The effect of racial residential segregation on black infant mortality.

Economic differences and proximal risk factors do not fully explain the persistent high infant mortality rates of African Americans (blacks). The authors hypothesized that racial residential segregation plays an independent role in high black infant mortality rates. Segregation restricts social and economic advantage and imposes negative environmental exposures that black women and infants experience. The study sample was obtained from the 2000-2002 US Linked Birth/Infant Death records and included 677,777 black infants residing in 64 cities with 250,000 or more residents. Outcomes were rates of all-cause infant mortality, postneonatal mortality, and external causes of death. Segregation was measured by using the isolation index (dichotomized at 0.60) from the 2000 US Census Housing Patterns. Propensity score matching methods were used. After matching on propensity scores, no independent effect of segregation on black infant mortality rates was found. Results show little statistical evidence that segregation plays an independent role in black infant mortality. However, a key finding is that it is difficult to disentangle contextual effects from the characteristics of individuals.