How to ensure that national radon survey results are useful for public health practice

Exposure to radon gas increases the risk of lung cancer. Preliminary national survey data collected by Health Canada indicate that approximately 10% of households exceed the recommended federal long-term guideline of 200 Bq/m3. However, results to date have been reported for large geographic areas in broad measurement categories. Given that Health Canada recommends the most rapid remediation for buildings with the highest concentrations, such reporting makes it challenging for public health authorities to target interventions to communities at the highest risk. Here we use data from a survey in British Columbia to illustrate how improved spatial resolution and more refined concentration categories would be valuable for prioritizing the use of limited public health resources. We encourage Health Canada in future to provide more specific, community-level information that can be used to inform local policy and to engage building owners in radon testing and remediation.     

Strength and comprehensiveness of district school wellness policies predict policy implementation at the school level

BACKGROUND: In 2006, all local education agencies in the United States participating in federal school meal programs were required to establish school wellness policies. This study documented the strength and comprehensiveness of 1 state's written district policies using a coding tool, and tested whether these traits predicted school‐level implementation and practices. METHODS: School wellness policies from 151 Connecticut districts were evaluated. School principal surveys were collected before and after the writing and expected implementation of wellness policies. Sociodemographic variables were assessed for each district, including enrollment, population density, political climate, racial composition, and socioeconomic status. Changes in school‐level policy implementation before and after the federal wellness policy mandate were compared across districts by wellness policy strength; policies were compared based on district‐level demographics. RESULTS: Statewide, more complete implementation of nutrition and physical activity policies at the school level was reported after adoption of written policies. Districts with stronger, more comprehensive policies were more successful in implementing them at the school level. Some sociodemographic characteristics predicted the strength of wellness policies. CONCLUSIONS: Written school wellness policies have the potential to promote significant improvements in the school environment. Future regulation of school wellness policies should focus on the importance of writing strong and comprehensive policies.     

Estimated global mortality attributable to smoke from landscape fires

Background: Forest, grass, and peat fires release approximately 2 petagrams of carbon into the atmosphere each year, influencing weather, climate, and air quality.Objective: We estimated the annual global mortality attributable to landscape fire smoke (LFS).Methods: Daily and annual exposure to particulate matter ≤ 2.5 μm in aerodynamic diameter (PM_2.5) from fire emissions was estimated globally for 1997 through 2006 by combining outputs from a chemical transport model with satellite-based observations of aerosol optical depth. In World Health Organization (WHO) subregions classified as sporadically affected, the daily burden of mortality was estimated using previously published concentration–response coefficients for the association between short-term elevations in PM_2.5 from LFS (contrasted with 0 μg/m³ from LFS) and all-cause mortality. In subregions classified as chronically affected, the annual burden of mortality was estimated using the American Cancer Society study coefficient for the association between long-term PM_2.5 exposure and all-cause mortality. The annual average PM_2.5 estimates were contrasted with theoretical minimum (counterfactual) concentrations in each chronically affected subregion. Sensitivity of mortality estimates to different exposure assessments, counterfactual estimates, and concentration–response functions was evaluated. Strong La Niña and El Niño years were compared to assess the influence of interannual climatic variability.Results: Our principal estimate for the average mortality attributable to LFS exposure was 339,000 deaths annually. In sensitivity analyses the interquartile range of all tested estimates was 260,000–600,000. The regions most affected were sub-Saharan Africa (157,000) and Southeast Asia (110,000). Estimated annual mortality during La Niña was 262,000, compared with 532,000 during El Niño.Conclusions: Fire emissions are an important contributor to global mortality. Adverse health outcomes associated with LFS could be substantially reduced by curtailing burning of tropical rainforests, which rarely burn naturally. The large estimated influence of El Niño suggests a relationship between climate and the burden of mortality attributable to LFS.     

Shifts in Mortality During a Hot Weather Event in Vancouver,British Columbia: Rapid Assessment With Case-Only Analysis

Objectives. We assessed shifts in patterns of mortality during a hot weather event in greater Vancouver, British Columbia.Methods. We used a case-only analysis to compare characteristics of individuals who died during the hottest week of 2009 with those who died (1) during earlier summer weeks in 2009 and (2) during the same calendar weeks in the summers of 2001 through 2008.Results. Compared with the 8 previous weeks of 2009, odds of mortality during the summer’s hottest week were highest in the 65 to 74 years age category, compared with the 85 years and older category (odds ratio [OR] = 1.47; 95% confidence interval [CI] = 1.06, 2.03). The number of deaths at home increased over deaths in hospitals or institutions (OR = 1.43; 95% CI = 1.10, 1.86). Densely populated administrative health areas were more affected.Conclusions. A shift toward deaths at home suggests that in-home–based protective measures should be part of planning for hot weather events in greater Vancouver. Targeting should be considered for those aged 65 to 74 years. The case-only approach is quick and easy to apply and can provide useful information about localized, time-limited events.Climate change has heightened public health interest in the epidemiology of death associated with very high temperatures. Although recent heat waves affecting Chicago, Illinois,1,2 and Paris, France,3,4 have been studied, other hot weather events have passed largely unreported.5,6 In this article, we show that rapid assessment of impacts and risk factors can be facilitated by methods that use easily accessed administrative health data to compare groups of decedents.Case-only analyses were originally used to study gene–environment interactions7,8 but have recently been applied to assess the effects of weather and air pollution on mortality.9 Case-only analyses have been used to examine sensitivity to extreme temperatures across multiple cities over lengthy study periods10,11 but have not been applied to specific hot weather events in defined geographic regions. Benefits of the case-only design include simplification of data analysis and reduction in model complexity.9During summer 2009, Vancouver, British Columbia, and its surrounding suburban and semirural areas (i.e., greater Vancouver) experienced an atypically hot weather event. The maximum (and minimum) temperatures at Vancouver International Airport were 30.9°C (19.6°C) on July 28, 34.0°C (20.2°C) on July 29, and 34.4°C (22.4°C) on July 30, all under clear skies with an average relative humidity of 57%. By comparison, the 10-year (1999–2008) average of maximum (and minimum) daily temperature for July 28 to 30 was 21.9°C (14.1°C), with an average relative humidity of 68%. Within days of the onset of the hot weather event, British Columbia’s rapid mortality surveillance system indicated that deaths among residents of greater Vancouver had increased by around 40% for the period through August 2. The objective of this case-only analysis was to examine whether patterns of mortality in greater Vancouver shifted during this hot weather event by comparing characteristics of the individuals who died during the hottest calendar week with those of the individuals who died during 3 comparison periods.     

Design of a Randomized Controlled Trial of a Web-Based Intervention to Reduce Cardiovascular Disease Risk Factors Among Remote Reservation–Dwelling American Indian Adults with Type 2 Diabetes

We describe a randomized controlled trial, the Lakota Oyate Wicozani Pi Kte (LOWPK) trial, which was designed to determine whether a Web-based diabetes and nutritional intervention can improve risk factors related to cardiovascular disease (CVD) among a group of remote reservation?Cdwelling adult American Indian men and women with type 2 diabetes who are at high risk for CVD. Enrollment on a rolling basis of 180 planned participants began during 2009; an average 18-month follow-up was completed by June 2011. The primary outcome variable is change in glycosylated hemoglobin level after an average 18-month follow-up period. Secondary outcome variables include changes in low-density lipoprotein cholesterol, systolic blood pressure, body mass index, and smoking status, as well as an evaluation of intervention cost-effectiveness. If effective, the LOWPK trial may serve as a guide for future chronic disease intervention trials in remote, technologically challenged settings.     

Mapping social processes at work in nursing knowledge development

In this paper, we suggest a blueprint for combining bibliometrics and critical analysis as a way to review published scientific works in nursing. This new approach is neither a systematic review nor meta‐analysis. Instead, it is a way for researchers and clinicians to understand how and why current nursing knowledge developed as it did. Our approach will enable consumers and producers of nursing knowledge to recognize and take into account the social processes involved in the development, evaluation, and utilization of new nursing knowledge. We offer a rationale and a strategy for examining the socially‐sanctioned actions by which nurse scientists signal to readers the boundaries of their thinking about a problem, the roots of their ideas, and the significance of their work. These actions – based on social processes of authority, credibility, and prestige – have bearing on the careers of nurse scientists and on the ways the knowledge they create enters into the everyday world of nurse clinicians and determines their actions at the bedside, as well as their opportunities for advancement.