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Lung cancer is the most common malignancy in the United States and is ranked second only to bladder cancer in the proportion of cases thought to be due to occupational exposures. We review the epidemiology of occupational lung cancer, focusing on agents identified as pulmonary carcinogens by the International Agency for Research on Cancer. We derive estimates of overall relative risks from the major studies of these lung carcinogens, and we also provide estimates of the number of exposed workers. Using our data as well as estimates from other authors, we estimate that approximately 9,000–10,000 men and 900–1,900 women develop lung cancer annually in the United States due to past exposure to occupational carcinogens. More than half of these lung cancers are due to asbestos. This estimate is likely conservative, in that we have restricted our analysis to confirmed lung carcinogens and have ignored occupations with documented excess risk but for which the specific agents are unknown. Also, our estimate of the proportion of workers exposed in the past is probably too low. Our estimate should be viewed only as a broad approximation. Nevertheless, it is in line with other estimates by authors using different methods. The current number of cases estimated to be due to occupational exposures reflects past high exposures and is likely to drop in the future, unless other occupational lung carcinogens are confirmed or new carcinogens are introduced into the workplace. (This article is a US Government work and, as such, is in the public domain in the United States of America.) © 1996 Wiley‐Liss, Inc.

Abstract. Many previous studies have suggested a link between alcohol outlets and assaultive violence. In this paper, we evaluate the impact of the "1992 Civil Unrest" in Los Angeles (which followed the "Rodney King incident"), in which many alcohol outlets were damaged leading to a decrease in alcohol outlet density, on crime. We leverage the natural experiment created by the closure of alcohol outlets in certain areas and not others to explore the effects of alcohol availability on assault crimes at the census tract level. We develop a hierarchical model that controls for important covariates (such as race and socio-economic status) and accounts for unexplained spatial and temporal variability. While our model is somewhat complex, its hierarchical Bayesian analysis is accessible via the WinBUGS software. Our results show that, keeping other effects fixed, the reduction in alcohol availability within a census tract was associated with a drop in the assaultive violence rate at the census tract level. Comparing several dual candidate changepoint models using the Deviance Information Criterion, the drop in assaultive violence rate is best seen as having occurred one year after the reduction in alcohol availability, with the effect lasting roughly five years. We also create maps of the fitted assault rates in Los Angeles, as well as spatial residual maps that suggest various spatially-varying covariates are still missing from our model.

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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 modeling, few have explored the impact of group size < 5. Methods In a simulated analysis of real data, we examined the impact of group size < 5 on both a continuous and dichotomous outcome in a simple two-level multilevel model. Models with group sizes 1 to 5 were compared to 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. We further evaluated 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 1 individual per tract and even when an aggregated group -level covariate was examined. As the number of groups decreased, the standard error estimates of both fixed and random effects were inflated. Furthermore, group-level variance estimates were more affected than were fixed components. Conclusions Datasets where there are a small to moderate number of groups with the majority 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 under-powered to detect fixed effects.

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.

A 14-site randomized trial tested the effectiveness of social norms marketing (SNM) campaigns, which present accurate student survey data in order to correct misperceptions of subjective drinking norms and thereby drive down alcohol use. Cross-sectional student surveys were conducted by mail at baseline and at posttest 3 years later. Hierarchical linear modeling was applied to examine multiple drinking outcomes, taking into account the nonindependence of students grouped in the same college. Controlling for other predictors, having a SNM campaign was not significantly associated with lower perceptions of student drinking levels or lower self-reported alcohol consumption. This study failed to replicate a previous multisite randomized trial of SNM campaigns, which showed that students attending institutions with a SNM campaign had a lower relative risk of alcohol consumption than students attending control group institutions (W. DeJong et al. J Stud Alcohol. 2006;67:868-879). Additional research is needed to explore whether SNM campaigns are less effective in campus communities with relatively high alcohol retail outlet density.

The fatty acid content of adipose tissue in postmenopausal breast cancer cases and controls from five European countries in the European Community Multicenter Study on Antioxidants, Myocardial Infarction, and Cancer (EURAMIC) breast cancer study (1991 -1992) was used to explore the hypothesis that fatty acids of the omega-3 family inhibit breast cancer and that the degree of inhibition depends on background levels of omega-6 polyunsaturates. Considered in isolation, the level of omega-3 or omega-6 fat in adipose tissue displayed little consistent association with breast cancer across study centers. The ratio of long-chain omega-3 fatty acids to total omega-6 fat showed an inverse association with breast cancer in four of five centers. In Malaga, Spain, the odds ratio for the highest tertile relative to the lowest reached 0.32 (95% confidence interval 0.13-0.82). In this center, total omega-6 fatty acid was strongly associated with breast cancer. With all centers pooled, the odds ratio for long-chain omega-3 to total omega-6 reached 0.80 for the second tertile and 0.65 for the third tertile, a downward trend bordering on statistical significance (p for trend = 0.055). While not definitive, these results provide evidence for the hypothesis that the balance between omega-3 and omega-6 fat may play a role in breast cancer. Am J Epidemiol 1998;147:342-52. adipose tissue; breast neoplasms; fatty acids; fatty acids, omega-3Breast cancer rates vary greatly across industrialized nations. The incidence rate in the United States is nearly five times that of Japan. In the neighboring countries of Spain and France, annual female breast cancer incidences differ by 50 percent (86 and 129 per 100,000, respectively) (1). Despite clear associations of hormonal, reproductive, and genetic factors with breast cancer risk, most of the variation in occurrence across populations does not appear to be attributable to