Geocoding Large Population‐level Administrative Datasets at Highly Resolved Spatial Scales

Using geographic information systems to link administrative databases with demographic, social, and environmental data allows researchers to use spatial approaches to explore relationships between exposures and health. Traditionally, spatial analysis in public health has focused on the county, ZIP code, or tract level because of limitations to geocoding at highly resolved scales. Using 2005 birth and death data from North Carolina, we examine our ability to geocode population‐level datasets at three spatial resolutions – zip code, street, and parcel. We achieve high geocoding rates at all three resolutions, with statewide street geocoding rates of 88.0% for births and 93.2% for deaths. We observe differences in geocoding rates across demographics and health outcomes, with lower geocoding rates in disadvantaged populations and the most dramatic differences occurring across the urban‐rural spectrum. Our results suggest that highly resolved spatial data architectures for population‐level datasets are viable through geocoding individual street addresses. We recommend routinely geocoding administrative datasets to the highest spatial resolution feasible, allowing public health researchers to choose the spatial resolution used in analysis based on an understanding of the spatial dimensions of the health outcomes and exposures being investigated. Such research, however, must acknowledge how disparate geocoding success across subpopulations may affect findings.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108258/1/tgis12052.pd

Making the Environmental Justice Grade: The Relative Burden of Air Pollution Exposure in the United States

This paper assesses whether the Clean Air Act and its Amendments have been equally successful in ensuring the right to healthful air quality in both advantaged and disadvantaged communities in the United States. Using a method to rank air quality established by the American Lung Association in its 2009 State of the Air report along with EPA air quality data, we assess the environmental justice dimensions of air pollution exposure and access to air quality information in the United States. We focus on the race, age, and poverty demographics of communities with differing levels of ozone and particulate matter exposure, as well as communities with and without air quality information. Focusing on PM2.5 and ozone, we find that within areas covered by the monitoring networks, non-Hispanic blacks are consistently overrepresented in communities with the poorest air quality. The results for older and younger age as well as poverty vary by the pollution metric under consideration. Rural areas are typically outside the bounds of air quality monitoring networks leaving large segments of the population without information about their ambient air quality. These results suggest that substantial areas of the United States lack monitoring data, and among areas where monitoring data are available, low income and minority communities tend to experience higher ambient pollution levels

How informed is declared altruism in clinical trials? A qualitative interview study of patient decision-making about the QUEST trials (Quality of Life after Mastectomy and Breast Reconstruction)

Background Randomised controlled trials (RCTs) often fail to recruit sufficient participants, despite altruism being cited as their motivation. Previous investigations of factors influencing participation decisions have been methodologically limited. This study evaluated how women weigh up different motivations after initially expressing altruism, and explored their understanding of a trial and its alternatives. The trial was the 'Quality of Life after Mastectomy and Breast Reconstruction' (QUEST) trial.Methods Thirty-nine women participated in qualitative interviews 1 month post-surgery. Twenty-seven women (10 trial decliners and 17 acceptors) who spontaneously mentioned 'altruism' were selected for thematic analysis. Verbatim transcripts were coded independently by two researchers. Participants' motivations to accept or decline randomisation were cross-referenced with their understanding of the QUEST trials and the process of randomisation.Results The seven emerging themes were: (1) altruism expressed by acceptors and decliners; (2) overriding personal needs in decliners; (3) pure altruism in acceptors; (4) 'hypothetical altruism' amongst acceptors; (5) weak altruism amongst acceptors; (6) conditional altruism amongst acceptors; and (7) sense of duty to participate. Poor understanding of the trial rationale and its implications was also evident.Conclusions Altruism was a motivating factor for participation in the QUEST randomised controlled trials where the main outcomes comprised quality of life and allocated treatments comprised established surgical procedures. Women's decisions were influenced by their understanding of the trial. Both acceptors and decliners of the trial expressed 'altruism', but most acceptors lacked an obvious treatment preference, hoped for personal benefits regarding a treatment allocation, or did not articulate complete understanding of the trial.Trial registration QUEST A, ISRCTN38846532 ; Date assigned 6 January 2010. QUEST B, ISRCTN92581226 ; Date assigned 6 January 2010

Lake sedimentary DNA accurately records 20th Century introductions of exotic conifers in Scotland

Summary:Sedimentary DNA (sedDNA) has recently emerged as a new proxy for reconstructing past vegetation, but its taphonomy, source area and representation biases need better assessment. We investigated how sedDNA in recent sediments of two small Scottish lakes reflects a major vegetation change, using well-documented 20th Century plantations of exotic conifers as an experimental system. We used next-generation sequencing to barcode sedDNA retrieved from subrecent lake sediments. For comparison, pollen was analysed from the same samples. The sedDNA record contains 73 taxa (mainly genus or species), all but one of which are present in the study area. Pollen and sedDNA shared 35% of taxa, which partly reflects a difference in source area. More aquatic taxa were recorded in sedDNA, whereas taxa assumed to be of regional rather than local origin were recorded only as pollen. The chronology of the sediments and planting records are well aligned, and sedDNA of exotic conifers appears in high quantities with the establishment of plantations around the lakes. SedDNA recorded other changes in local vegetation that accompanied afforestation. There were no signs of DNA leaching in the sediments or DNA originating from pollen

Diversity from genes to ecosystems : a unifying framework to study variation across biological metrics and scales

This work was assisted through participation in “Next Generation Genetic Monitoring” Investigative Workshop at the National Institute for Mathematical and Biological Synthesis, sponsored by the National Science Foundation through NSF Award #DBI-1300426, with additional support from The University of Tennessee, Knoxville. Hawaiian fish community data were provided by the NOAA Pacific Islands Fisheries Science Center's Coral Reef Ecosystem Division (CRED) with funding from NOAA Coral Reef Conservation Program. O.E.G. was supported by the Marine Alliance for Science and Technology for Scotland (MASTS). A. C. and C. H. C. were supported by the Ministry of Science and Technology, Taiwan. P.P.-N. was supported by a Canada Research Chair in Spatial Modelling and Biodiversity. K.A.S. was supported by National Science Foundation (BioOCE Award Number 1260169) and the National Center for Ecological Analysis and Synthesis. All data used in this manuscript are available in DRYAD (https://doi.org/dx.doi.org/10.5061/dryad.qm288) and BCO-DMO (http://www.bco-dmo.org/project/552879).Biological diversity is a key concept in the life sciences and plays a fundamental role in many ecological and evolutionary processes. Although biodiversity is inherently a hierarchical concept covering different levels of organisation (genes, population, species, ecological communities and ecosystems), a diversity index that behaves consistently across these different levels has so far been lacking, hindering the development of truly integrative biodiversity studies. To fill this important knowledge gap we present a unifying framework for the measurement of biodiversity across hierarchical levels of organisation. Our weighted, information-based decomposition framework is based on a Hill number of order q = 1, which weights all elements in proportion to their frequency and leads to diversity measures based on Shannon’s entropy. We investigated the numerical behaviour of our approach with simulations and showed that it can accurately describe complex spatial hierarchical structures. To demonstrate the intuitive and straightforward interpretation of our diversity measures in terms of effective number of components (alleles, species, etc.) we applied the framework to a real dataset on coral reef biodiversity. We expect our framework will have multiple applications covering the fields of conservation biology, community genetics, and eco-evolutionary dynamics.Publisher PDFPeer reviewe

Cadmium levels in a North Carolina cohort: Identifying risk factors for elevated levels during pregnancy

The objectives of this study were to examine cadmium (Cd) levels and relationships to demographics in an observational, prospective pregnancy cohort study in Durham County, North Carolina. Multivariable models were used to compare blood Cd levels across demographic characteristics. The relative risk of having a blood Cd level that exceeds the US national median (0.32 μg/l) was estimated. Overall, >60% of the women had an elevated (>0.32 μg/l) blood Cd level. Controlling for confounding variables, smoking was associated with 21% (95% CI: 15–28%) increased risk for an elevated blood Cd level. High Cd levels were also observed in non-smokers and motivated smoking status-stratified models. Race, age, education, relationship status, insurance status and cotinine level were not associated with risk of elevated Cd levels among smokers; however, older age and higher cotinine levels were associated with elevated Cd levels among non-smokers. Taken together, more than half of pregnant women in this cohort had elevated blood Cd levels. Additionally, among non-smokers, 53% of the women had elevated levels of Cd, highlighting other potential sources of exposure. This study expands on the limited data describing Cd levels in pregnant populations and highlights the importance of understanding Cd exposures among non-smokers. Given the latent health risks of both smoking and Cd exposure, this study further highlights the need to biomonitor for exposure to toxic metals during pregnancy among all women of child-bearing age

Real-world comparison of two molecular methods for detection of respiratory viruses

Background: Molecular polymerase chain reaction (PCR) based assays are increasingly used to diagnose viral respiratory infections and conduct epidemiology studies. Molecular assays have generally been evaluated by comparing them to conventional direct fluorescent antibody (DFA) or viral culture techniques, with few published direct comparisons between molecular methods or between institutions. We sought to perform a real-world comparison of two molecular respiratory viral diagnostic methods between two experienced respiratory virus research laboratories.Methods: We tested nasal and throat swab specimens obtained from 225 infants with respiratory illness for 11 common respiratory viruses using both a multiplex assay (Respiratory MultiCode-PLx Assay [RMA]) and individual real-time RT-PCR (RT-rtPCR).Results: Both assays detected viruses in more than 70% of specimens, but there was discordance. The RMA assay detected significantly more human metapneumovirus (HMPV) and respiratory syncytial virus (RSV), while RT-rtPCR detected significantly more influenza A. We speculated that primer differences accounted for these discrepancies and redesigned the primers and probes for influenza A in the RMA assay, and for HMPV and RSV in the RT-rtPCR assay. The tests were then repeated and again compared. The new primers led to improved detection of HMPV and RSV by RT-rtPCR assay, but the RMA assay remained similar in terms of influenza detection.Conclusions: Given the absence of a gold standard, clinical and research laboratories should regularly correlate the results of molecular assays with other PCR based assays, other laboratories, and with standard virologic methods to ensure consistency and accuracy

Cohort Profile: The Study of Respiratory Pathogens in Andean Children

We investigated respiratory pathogens in a prospective cohort study of young children living in the Peruvian Andes. In the study we assessed viral respiratory infections among young children, and explored interactions of viruses with common respiratory bacteria, especially Streptococcus pneumoniae. Through weekly household visits, data were collected on the signs and symptoms of acute respiratory illness (ARI), nasal samples were collected to test for viruses during episodes of ARI, and nasopharyngeal samples were collected on a monthly basis to monitor bacterial colonisation. We also collected data on vaccination coverage, patterns of social mixing, geographic information, and environmental and socio-demographic variables. Understanding the interaction of respiratory viruses with bacteria and its impact on the burden and severity of ARIs in rural areas of developing countries is critical to designing strategies for preventing such infections. Investigators interested in more details about this study or in accessing these resources should contact Dr. Carlos G. Grijalva at Vanderbilt University ([email protected]