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Objective: To test whether a frequently used cohort-nested case-control study design exaggerated exposure-response relationships because of unrecognized study design bias. Our aim was to evaluate empirically the performance of this complex study design., Methods: We applied the design from one such study to a closely related cohort using randomly selected probands as cases. Values for average exposures were assigned to probands equal to, greater than, and less than those assigned to controls (matches)., Results: Under certain lag scenarios, the nested study design produced higher average exposure in probands compared with their matches, even when this was clearly not the case., Conclusions: Empirical evaluation demonstrated that the study design produced a biased case-control lagged exposure difference under the null hypothesis and could not distinguish qualitatively between null and alternate hypotheses. Empirical evaluation provided a useful check on results generated from a complex study design. It gave useful insight into the behavior of the index study design that was not otherwise readily deducible.

Objective: Our aim was to reanalyze a nested case-control study of beryllium and lung cancer because we identified analysis and study design issues that could have led to the elevated odds ratios obtained in the study., Methods: We reanalyzed the data using nontransformed exposure metrics instead of log-transformed metrics used in the publication. We identified and examined effects on estimated odds ratios of imbalances between cases and controls caused by the control selection method., Results: This reanalysis found no elevated odds ratios for any exposure variable., Conclusion: : Our conclusions differ from the authors' interpretation that the findings are due to a causal relationship between beryllium exposure and lung cancer. Our alternative explanation is that they may be due to methodological problems that could have been controlled by closer matching of controls to cases., Clinical Significance: This study challenges conclusions made from a large case-control study concerning beryllium-lung cancer associations. Occupational medicine practitioners may want to integrate findings from this study into advice they give beryllium-exposed workers concerned about lung cancer.

Background: During the 2004-2005 influenza season, the United States faced a sudden shortage of influenza vaccine. In response, the Centers for Disease Control and Prevention (CDC) and the Advisory Committee on Immunization Practices (ACIP) recommended prioritizing vaccination for persons aged 65 and older and others at high risk. To monitor subsequent vaccination coverage, several questions about influenza vaccination were added to the ongoing Behavioral Risk Factor Surveillance System (BRFSS). This study provided real-time county-level estimates of influenza vaccination coverage from the BRFSS each month from October 2004 through January 2005., Method: The methods used a variation of small area estimation procedures suitable for situations in which most small areas have few or no survey respondents, and rapid assessment is essential. Both model-based methods and nonparametric spatial-smoothing methods were used in a three-step procedure., Results: The highest vaccination rates during the 2004-2005 influenza season were seen in the upper Midwest and the Southeast. Areas with the lowest vaccination rates were the intermountain West, southern California, portions of Washington and Oregon, and various areas across the Eastern United States, often coinciding with urban areas. Intrastate variations were especially pronounced in the Eastern United States, particularly in Georgia, Florida, Tennessee, Kentucky, North Carolina, Virginia, and New York. These states all had areas with low immunization rates as well as areas with high rates., Conclusions: The results showed that vaccination coverage varied significantly across states and substate regions. Our findings show that this methodology can provide estimates with reasonable reliability for planning during public health emergencies.

Background: The goal of the National Smallpox Vaccination Program was to vaccinate a cadre of healthcare workers and first responders who could care for smallpox patients in the event of an attack., Methods: Using a convenience sample of health departments (n=49) and hospitals (n=60) in five states, we conducted a telephone interview between July 2003 and April 2004 of healthcare workers and first responders who chose not to receive smallpox vaccination. (Data were analyzed in 2004 and 2005.), Results: The response rate was 63%. Of 1895 respondents, 723 (38.2%) reported having a contraindication, 280 (14.8%) reported being contraindicated because of a household member's condition, and 892 (47.0%) reported having no contraindication to smallpox vaccination. Among respondents with no contraindication, the leading reasons for nonvaccination were concerns about side effects (20.6%) and not feeling that the risk of outbreak was high enough (19.5%). More than half (54.8%) were somewhat or very concerned about having an adverse reaction to the vaccine; Hispanics, blacks, and Asians were significantly more likely than whites to be somewhat or very concerned about side effects. Less than one fifth (17.9%) reported that there was a policy to financially compensate employees who developed side effects from vaccination, and 40.7% reported that there was a policy to provide liability coverage to employees who transmitted vaccinia to a patient., Conclusions: Many people who chose not to receive smallpox vaccine perceived their personal risk-benefit balance as not favoring vaccination. The success of future smallpox vaccination efforts or vaccination against other bioterrorist health threats depends on addressing potential barriers to participation including compensation and liability issues, in addition to clearly communicating risks and benefits.