Editorial--Avoiding Unethical Helicobacter pylori Clinical Trials: Susceptibility-Based Studies and Probiotics as Adjuvants.

PubMed

Graham, David Y

2015-10-01

As a general rule, any clinical study where the result is already known or when the investigator(s) compares an assigned treatment against another assigned treatment known to be ineffective in the study population (e.g., in a population with known clarithromycin resistance) is unethical. As susceptibility-based therapy will always be superior to empiric therapy in any population with a prevalence of antimicrobial resistance >0%, any trial that randomizes susceptibility-based therapy with empiric therapy would be unethical. The journal Helicobacter welcomes susceptibility or culture-guided studies, studies of new therapies, and studies of adjuvants and probiotics. However, the journal will not accept for review any study we judge to be lacking clinical equipoise or which assign subjects to a treatment known to be ineffective, such as a susceptibility-based clinical trial with an empiric therapy comparator. To assist authors, we provide examples and suggestions regarding trial design for comparative studies, for susceptibility-based studies, and for studies testing adjuvants or probiotics. © 2015 John Wiley & Sons Ltd.

Editorial - Avoiding unethical Helicobacter pylori clinical trials: Susceptibility-based studies and probiotics as adjuvants

PubMed Central

Graham, David Y.

2016-01-01

As a general rule, any clinical study where the result is already known or when the investigator(s) compares an assigned treatment against another assigned treatment known to be ineffective in the study population (e.g. in a population with known clarithromycin resistance) is unethical. Since susceptibility-based therapy will always be superior to empiric therapy in any population with a prevalence of antimicrobial resistance greater than 0%, any trial that randomizes susceptibility-based therapy with empiric therapy would be unethical. The journal Helicobacter welcomes susceptibility or culture-guided studies, studies of new therapies and of adjuvants and probiotics. However, the Journal will not accept for review any study we judge to be lacking clinical equipoise or which assign subjects to a treatment known to be ineffective, such as a susceptibility-based clinical trial with an empiric therapy comparator. To assist authors we provide examples and suggestion regarding trial design for comparative studies, for susceptibility-based studies, and for studies testing adjuvants or probiotics. PMID:26123529

Beyond genome-wide association studies: genetic heterogeneity and individual predisposition to cancer

PubMed Central

Galvan, Antonella; Ioannidis, John P.A.; Dragani, Tommaso A.

2010-01-01

Genome-wide association studies (GWAS) using population-based designs have identified many genetic loci associated with risk of a range of complex diseases including cancer; however, each locus exerts a very small effect and most heritability remains unexplained. Family-based pedigree studies have also suggested tentative loci linked to increased cancer risk, often characterized by pedigree-specificity. However, a comparison between the results of population-and those of family-based studies shows little concordance. Explanations for this unidentified genetic ‘dark matter’ of cancer include phenotype ascertainment issues, limited power, gene-gene and gene-environment interactions, population heterogeneity, parent-of-origin-specific effects, rare and unexplored variants. Many of these reasons converge towards the concept of genetic heterogeneity that might implicate hundreds of genetic variants in regulating cancer risk. Dissecting the dark matter is a challenging task. Further insights can be gained from both population association and pedigree studies. PMID:20106545

Feasibility of Population Health Analytics and Data Visualization for Decision Support in the Infectious Diseases Domain

PubMed Central

Del Fiol, Guilherme; Butler, Jorie; Livnat, Yarden; Mayer, Jeanmarie; Samore, Matthew; Jones, Makoto; Weir, Charlene

2016-01-01

Summary Objective Big data or population-based information has the potential to reduce uncertainty in medicine by informing clinicians about individual patient care. The objectives of this study were: 1) to explore the feasibility of extracting and displaying population-based information from an actual clinical population’s database records, 2) to explore specific design features for improving population display, 3) to explore perceptions of population information displays, and 4) to explore the impact of population information display on cognitive outcomes. Methods We used the Veteran’s Affairs (VA) database to identify similar complex patients based on a similar complex patient case. Study outcomes measures were 1) preferences for population information display 2) time looking at the population display, 3) time to read the chart, and 4) appropriateness of plans with pre- and post-presentation of population data. Finally, we redesigned the population information display based on our findings from this study. Results The qualitative data analysis for preferences of population information display resulted in four themes: 1) trusting the big/population data can be an issue, 2) embedded analytics is necessary to explore patient similarities, 3) need for tools to control the view (overview, zoom and filter), and 4) different presentations of the population display can be beneficial to improve the display. We found that appropriateness of plans was at 60% for both groups (t9=-1.9; p=0.08), and overall time looking at the population information display was 2.3 minutes versus 3.6 minutes with experts processing information faster than non-experts (t8= -2.3, p=0.04). Conclusion A population database has great potential for reducing complexity and uncertainty in medicine to improve clinical care. The preferences identified for the population information display will guide future health information technology system designers for better and more intuitive display. PMID:27437065

Does Marital Status Predict the Odds of Suicidal Death in Taiwan? A Seven-Year Population-Based Study

ERIC Educational Resources Information Center

Yeh, Jui-Yuan; Xirasagar, Sudha; Liu, Tsai-Ching; Li, Chong-Yi; Lin, Herng-Ching

2008-01-01

Using nationwide, 7-year population-based data for 1997-2003, we examined marital status to see if it predicted suicide among the ethnic Chinese population of Taiwan. Using cause of death data, with a case-control design, two groups--total adult suicide deaths, n = 17,850, the study group, and adult deaths other than suicide, n = 71,400 (randomly…

Recruitment Strategies and Costs Associated with Community-Based Research in a Mexican-Origin Population

ERIC Educational Resources Information Center

Mendez-Luck, Carolyn A.; Trejo, Laura; Miranda, Jeanne; Jimenez, Elizabeth; Quiter, Elaine S.; Mangione, Carol M.

2011-01-01

Purpose: We describe the recruitment strategies and personnel and materials costs associated with two community-based research studies in a Mexican-origin population. We also highlight the role that academic-community partnerships played in the outreach and recruitment process for our studies. We reviewed study documents using case study…

Prevalence of Tourette Syndrome and Chronic Tics in the Population-Based Avon Longitudinal Study of Parents and Children Cohort

ERIC Educational Resources Information Center

Scharf, Jeremiah M.; Miller, Laura L.; Mathews, Carol A.; Ben-Shlomo, Yoav

2012-01-01

Objective: Recent epidemiologic studies have demonstrated that Tourette syndrome (TS) and chronic tic disorder (CT) are more common than previously recognized. However, few population-based studies have examined the prevalence of co-occurring neuropsychiatric conditions such as obsessive-compulsive disorder (OCD) and…

Asthma and Attention-Deficit/Hyperactivity Disorder: A Nationwide Population-Based Prospective Cohort Study

ERIC Educational Resources Information Center

Chen, Mu-Hong; Su, Tung-Ping; Chen, Ying-Sheue; Hsu, Ju-Wei; Huang, Kai-Lin; Chang, Wen-Han; Chen, Tzeng-Ji; Bai, Ya-Mei

2013-01-01

Background: Previous cross-sectional studies have suggested an association between asthma and attention-deficit/hyperactivity disorder (ADHD), but the temporal relationship was not determined. Using a nationwide population-based prospective case-control cohort study (1:4, age-/gender-matched), we hypothesized that asthma in infanthood or early…

POPULATION-BASED EXPOSURE MEASUREMENTS IN ARIZONA: A PHASE FIELD STUDY IN SUPPORT OF THE NATIONAL HUMAN EXPOSURE ASSESSMENT SURVEY

EPA Science Inventory

The objectives of this field study are to determine the distributions of total human exposures to multi-media pollutants in the classes of metals, pesticides, and volatile organic compounds (VOCs) by studying a proportionate-based sample of the total population (with a nested des...

Predictors of Disordered Eating in Adolescence and Young Adulthood: A Population-Based, Longitudinal Study of Females and Males in Norway

ERIC Educational Resources Information Center

Abebe, Dawit Shawel; Torgersen, Leila; Lien, Lars; Hafstad, Gertrud S.; von Soest, Tilmann

2014-01-01

We investigated longitudinal predictors for disordered eating from early adolescence to young adulthood (12-34 years) across gender and different developmental phases among Norwegian young people. Survey data from a population-based sample were collected at four time points (T) over a 13-year time span. A population-based sample of 5,679 females…

Brief Report: Prevalence of Self-Injurious Behaviors among Children with Autism Spectrum Disorder--A Population-Based Study

ERIC Educational Resources Information Center

Soke, Gnakub N.; Rosenberg, Steven A.; Hamman, Richard F.; Fingerlin, Tasha; Robinson, Cordelia; Carpenter, Laura; Giarelli, Ellen; Lee, Li-Ching; Wiggins, Lisa D.; Durkin, Maureen S.; DiGuiseppi, Carolyn

2016-01-01

Self-injurious behaviors (SIB) have been reported in more than 30% of children with an autism spectrum disorder (ASD) in clinic-based studies. This study estimated the prevalence of SIB in a large population-based sample of children with ASD in the United States. A total of 8,065 children who met the surveillance case definition for ASD in the…

Mean population salt intake estimated from 24-h urine samples and spot urine samples: a systematic review and meta-analysis.

PubMed

Huang, Liping; Crino, Michelle; Wu, Jason H Y; Woodward, Mark; Barzi, Federica; Land, Mary-Anne; McLean, Rachael; Webster, Jacqui; Enkhtungalag, Batsaikhan; Neal, Bruce

2016-02-01

Estimating equations based on spot urine samples have been identified as a possible alternative approach to 24-h urine collections for determining mean population salt intake. This review compares estimates of mean population salt intake based upon spot and 24-h urine samples. We systematically searched for all studies that reported estimates of daily salt intake based upon both spot and 24-h urine samples for the same population. The associations between the two were quantified and compared overall and in subsets of studies. A total of 538 records were identified, 108 were assessed as full text and 29 were included. The included studies involved 10,414 participants from 34 countries and made 71 comparisons available for the primary analysis. Overall average population salt intake estimated from 24-h urine samples was 9.3 g/day compared with 9.0 g/day estimated from the spot urine samples. Estimates based upon spot urine samples had excellent sensitivity (97%) and specificity (100%) at classifying mean population salt intake as above or below the World Health Organization maximum target of 5 g/day. Compared with the 24-h samples, estimates based upon spot urine overestimated intake at lower levels of consumption and underestimated intake at higher levels of consumption. Estimates of mean population salt intake based upon spot urine samples can provide countries with a good indication of mean population salt intake and whether action on salt consumption is required. Published by Oxford University Press on behalf of the International Epidemiological Association 2015. This work is written by US Government employees and is in the public domain in the US.

Cannibalism in discrete-time predator-prey systems.

PubMed

Chow, Yunshyong; Jang, Sophia R-J

2012-01-01

In this study, we propose and investigate a two-stage population model with cannibalism. It is shown that cannibalism can destabilize and lower the magnitude of the interior steady state. However, it is proved that cannibalism has no effect on the persistence of the population. Based on this model, we study two systems of predator-prey interactions where the prey population is cannibalistic. A sufficient condition based on the nontrivial boundary steady state for which both populations can coexist is derived. It is found via numerical simulations that introduction of the predator population may either stabilize or destabilize the prey dynamics, depending on cannibalism coefficients and other vital parameters.

Violence Reported by the Immigrant Population Is High as Compared with the Native Population in Southeast Spain

ERIC Educational Resources Information Center

Colorado-Yohar, S.; Tormo, M. J.; Salmeron, D.; Dios, S.; Ballesta, M.; Navarro, C.

2012-01-01

Immigrants constitute a population vulnerable to the problem of violence. This study sought to ascertain the prevalence of violence reported by the immigrant population in the Murcian Region of Spain and characterize the related factors, taking the country population as reference. A cross-sectional study was carried out based on a representative…

Predictors of Word-Reading Ability in 7-Year-Olds: Analysis of Data from a U.K. Cohort Study

ERIC Educational Resources Information Center

Russell, Ginny; Ukoumunne, Obioha C.; Ryder, Denise; Golding, Jean; Norwich, Brahm

2018-01-01

Previous U.K. population-based studies have found associations amongst early speech and language difficulties, socioeconomic disadvantage and children's word-reading ability later on. We examine the strength of these associations in a recent U.K. population-based birth cohort. Analyses were based on 13,680 participants. Linear regression models…

Computer-aided system of evaluation for population-based all-in-one service screening (CASE-PASS): from study design to outcome analysis with bias adjustment.

PubMed

Chen, Li-Sheng; Yen, Amy Ming-Fang; Duffy, Stephen W; Tabar, Laszlo; Lin, Wen-Chou; Chen, Hsiu-Hsi

2010-10-01

Population-based routine service screening has gained popularity following an era of randomized controlled trials. The evaluation of these service screening programs is subject to study design, data availability, and the precise data analysis for adjusting bias. We developed a computer-aided system that allows the evaluation of population-based service screening to unify these aspects and facilitate and guide the program assessor to efficiently perform an evaluation. This system underpins two experimental designs: the posttest-only non-equivalent design and the one-group pretest-posttest design and demonstrates the type of data required at both the population and individual levels. Three major analyses were developed that included a cumulative mortality analysis, survival analysis with lead-time adjustment, and self-selection bias adjustment. We used SAS AF software to develop a graphic interface system with a pull-down menu style. We demonstrate the application of this system with data obtained from a Swedish population-based service screen and a population-based randomized controlled trial for the screening of breast, colorectal, and prostate cancer, and one service screening program for cervical cancer with Pap smears. The system provided automated descriptive results based on the various sources of available data and cumulative mortality curves corresponding to the study designs. The comparison of cumulative survival between clinically and screen-detected cases without a lead-time adjustment are also demonstrated. The intention-to-treat and noncompliance analysis with self-selection bias adjustments are also shown to assess the effectiveness of the population-based service screening program. Model validation was composed of a comparison between our adjusted self-selection bias estimates and the empirical results on effectiveness reported in the literature. We demonstrate a computer-aided system allowing the evaluation of population-based service screening programs with an adjustment for self-selection and lead-time bias. This is achieved by providing a tutorial guide from the study design to the data analysis, with bias adjustment. Copyright © 2010 Elsevier Inc. All rights reserved.

Population-based age group specific annual incidence rates of symptomatic age-related macular degeneration.

PubMed

Saari, Jukka M

2014-01-01

To study the population-based annual incidence rates of exudative, dry and all cases of symptomatic age-related macular degeneration (AMD) in different age and sex groups. This is a one year, prospective, population-based study on all consecutive new patients with AMD in the hospital district of Central Finland. The diagnosis was confirmed in all patients with slit lamp biomicroscopy, optical coherence tomography (OCT) using a Spectralis HRA + OCT device, and the Heidelberg Eye Explorer 1.6.2.0 program. Fluorescein angiograms were taken when needed. The population-based annual incidence rates of all cases of symptomatic AMD increased from 0.03% (95% CI, 0.01-0.05%) in the age group 50-59 years to 0.82% (95% CI, 0.55-1.09%) in the age group 85-89 years and were 0.2% (95% CI, 0.17-0.24%) in exudative, 0.11% (95% CI, 0.09-0.14%) in dry, and 0.32% (95% CI, 0.28-0.36%) in all cases of AMD in the age group 60 years and older. During the next 20 years in Central Finland the population-based annual incidence rates can be estimated to increase to 0.27% (95% CI, 0.24-0.30%) in exudative, to 0.13% (95% CI, 0.11-0.15%) in dry, and to 0.41% (95% CI, 0.37-0.45%) in all cases of AMD in the age group 60 years and older. The population-based annual incidence of AMD did not show statistically significant differences between males and females (p>0.1). The population-based age-group specific annual incidence rates of symptomatic AMD of this study may help to plan health care provision for patients of AMD.

Use of Mobile Device Data To Better Estimate Dynamic Population Size for Wastewater-Based Epidemiology.

PubMed

Thomas, Kevin V; Amador, Arturo; Baz-Lomba, Jose Antonio; Reid, Malcolm

2017-10-03

Wastewater-based epidemiology is an established approach for quantifying community drug use and has recently been applied to estimate population exposure to contaminants such as pesticides and phthalate plasticizers. A major source of uncertainty in the population weighted biomarker loads generated is related to estimating the number of people present in a sewer catchment at the time of sample collection. Here, the population quantified from mobile device-based population activity patterns was used to provide dynamic population normalized loads of illicit drugs and pharmaceuticals during a known period of high net fluctuation in the catchment population. Mobile device-based population activity patterns have for the first time quantified the high degree of intraday, week, and month variability within a specific sewer catchment. Dynamic population normalization showed that per capita pharmaceutical use remained unchanged during the period when static normalization would have indicated an average reduction of up to 31%. Per capita illicit drug use increased significantly during the monitoring period, an observation that was only possible to measure using dynamic population normalization. The study quantitatively confirms previous assessments that population estimates can account for uncertainties of up to 55% in static normalized data. Mobile device-based population activity patterns allow for dynamic normalization that yields much improved temporal and spatial trend analysis.

On estimation of time-dependent attributable fraction from population-based case-control studies.

PubMed

Zhao, Wei; Chen, Ying Qing; Hsu, Li

2017-09-01

Population attributable fraction (PAF) is widely used to quantify the disease burden associated with a modifiable exposure in a population. It has been extended to a time-varying measure that provides additional information on when and how the exposure's impact varies over time for cohort studies. However, there is no estimation procedure for PAF using data that are collected from population-based case-control studies, which, because of time and cost efficiency, are commonly used for studying genetic and environmental risk factors of disease incidences. In this article, we show that time-varying PAF is identifiable from a case-control study and develop a novel estimator of PAF. Our estimator combines odds ratio estimates from logistic regression models and density estimates of the risk factor distribution conditional on failure times in cases from a kernel smoother. The proposed estimator is shown to be consistent and asymptotically normal with asymptotic variance that can be estimated empirically from the data. Simulation studies demonstrate that the proposed estimator performs well in finite sample sizes. Finally, the method is illustrated by a population-based case-control study of colorectal cancer. © 2017, The International Biometric Society.

Aspects of Quality of Life in Adults Diagnosed with Autism in Childhood: A Population-Based Study

ERIC Educational Resources Information Center

Billstedt, Eva; Gillberg, I. Carina; Gillberg, Christopher

2011-01-01

The present study is a long-term prospective follow-up study of a population-based cohort of 120 individuals diagnosed with autism in childhood, followed into late adolescence/early adulthood. Specific aims of the study were to attempt to measure and study social aspects/quality of life in those 108 individuals with autism alive and available for…

Seroprevalence of Toxocariasis in Children with Urticaria: A Population-based Study.

PubMed

Matos Fialho, Paula Mayara; Correa, Carlos Roberto Silveira; Lescano, Susana Zevallos

2017-10-01

This study described the prevalence of IgG class antibodies against Toxocara spp. and their association with urticaria in 2- to 12-year-old children. This population-based cross-sectional study was conducted between May 2012 and September 2014. The study sample comprised 168 children. Blood samples were collected to verify the presence of toxocariasis by using ELISA to detect IgG antibodies. The guardians of the children were interviewed to characterize the presence or absence of other diseases, such as urticaria. The presence of urticaria was observed in 38% of participants. The seroprevalence of toxocariasis in this population was 16%. This study confirmed a positive association between urticaria and positive serology for Toxocara and a negative independent association with canine contact and the number of household residents. There are no previous reports in the literature of a population-based study that correlates the presence of urticaria with serology for toxocariasis. © The Author [2017]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Linking population viability, habitat suitability, and landscape simulation models for conservation planning

Treesearch

Michael A. Larson; Frank R., III Thompson; Joshua J. Millspaugh; William D. Dijak; Stephen R. Shifley

2004-01-01

Methods for habitat modeling based on landscape simulations and population viability modeling based on habitat quality are well developed, but no published study of which we are aware has effectively joined them in a single, comprehensive analysis. We demonstrate the application of a population viability model for ovenbirds (Seiurus aurocapillus)...

Minor Self-Harm and Psychiatric Disorder: A Population-Based Study

ERIC Educational Resources Information Center

Skegg, Keren; Nada-Raja, Shyamala; Moffit, Terrie E.

2004-01-01

Little is known about the extent to which minor self-harm in the general population is associated with psychiatric disorder. A population-based sample of 980 young adults was interviewed independently about past-year suicidal and self-harm behavior and thoughts, and psychiatric disorders. Self-harm included self-harmful behaviors such as…

Dementia Research: Populations, Progress, Problems, and Predictions.

PubMed

Hunter, Sally; Smailagic, Nadja; Brayne, Carol

2018-05-16

Alzheimer's disease (AD) is a clinicopathologically defined syndrome leading to cognitive impairment. Following the recent failures of amyloid-based randomized controlled trials to change the course of AD, there are growing calls for a re-evaluation of basic AD research. Epidemiology offers one approach to integrating the available evidence. Here we examine relationships between evidence from population-based, clinicopathological studies of brain aging and a range of hypotheses from all areas of AD research. We identify various problems, including a lack of systematic approach to measurement of clinical and neuropathological factors associated with dementia in experimental and clinical settings, poor understanding of the strengths and weaknesses of different observational and experimental designs, a lack of clarity in relation to disease definitions from the clinical, neuropathological, and molecular perspectives, inadequate characterization of brain aging in the human population, difficulties in translation between laboratory-based and population-based evidence bases, and a lack of communication between different sections of the dementia research community. Population studies highlight complexity and predict that therapeutic approaches based on single disease features will not be successful. Better characterization of brain aging in the human population is urgently required to select biomarkers and therapeutic targets that are meaningful to human disease. The generation of detailed and reliable evidence must be addressed before progress toward therapeutic interventions can be made.

Population-based medical and disease management: an evaluation of cost and quality.

PubMed

Wise, Christopher G; Bahl, Vinita; Mitchell, Rita; West, Brady T; Carli, Thomas

2006-02-01

Reports by the Institute of Medicine and the Health Care Financing Administration have emphasized that the integration of medical care delivery, evidence-based medicine, and chronic care disease management may play a significant role in improving the quality of care and reducing medical care costs. The specific aim of this project is to assess the impact of an integrated set of care coordination tools and chronic disease management interventions on utilization, cost, and quality of care for a population of beneficiaries who have complementary health coverage through a plan designed to apply proactive medical and disease management processes. The utilization of health care services by the study population was compared to another population from the same geographic service area and covered by a traditional fee-for-service indemnity insurance plan that provided few medical or disease management services. Evaluation of the difference in utilization was based on the difference in the cost per-member-per-month (PMPM) in a 1-year measurement period, after adjusting for differences in fee schedules, case-mix and healthcare benefit design. After adjustments for both case-mix and benefit differences, the study group is $63 PMPM less costly than the comparison population for all members. Cost differences are largest in the 55-64 and 65 and above age groups. The study group is $115 PMPM lower than the comparison population for the age category of 65 years and older, after adjustments for case-mix and benefits. Health Plan Employer and Data Information Set (HEDIS)-based quality outcomes are near the 90th percentile for most indications. The cost outcomes of a population served by proactive, population-based disease management and complex care management, compared to an unmanaged population, demonstrates the potential of coordinated medical and disease management programs. Further studies utilizing appropriate methodologies would be beneficial.

A Population-Based Longitudinal Study of Depression in Children with Developmental Disabilities in Manitoba

ERIC Educational Resources Information Center

Shooshtari, Shahin; Brownell, Marni; Dik, Natalia; Chateau, Dan; Yu, C. T.; Mills, Rosemary S. L.; Burchill, Charles A.; Wetzel, Monika

2014-01-01

In this population-based study, prevalence of depression was estimated and compared between children with and without developmental disability (DD). Twelve years of administrative data were linked to identify a cohort of children with DD living in the Canadian province of Manitoba. Children in the study cohort were matched with children without DD…

A Population-Based Study of Preschoolers' Food Neophobia and Its Associations with Food Preferences

ERIC Educational Resources Information Center

Russell, Catherine Georgina; Worsley, Anthony

2008-01-01

Objective: This cross-sectional study was designed to investigate the relationships between food preferences, food neophobia, and children's characteristics among a population-based sample of preschoolers. Design: A parent-report questionnaire. Setting: Child-care centers, kindergartens, playgroups, day nurseries, and swimming centers. Subjects:…

[Genetic differentiation of Isaria farinosa populations in Anhui Province of East China].

PubMed

Sun, Zhao-Hong; Luan, Feng-Gang; Zhang, Da-Min; Chen, Ming-Jun; Wang, Bin; Li, Zeng-Zhi

2011-11-01

Isaria farinosa is an important entomopathogenic fungus. By using ISSR, this paper studied the genetic heterogeneity of six I. farinosa populations at different localities of Anhui Province, East China. A total of 98.5% polymorphic loci were amplified with ten polymorphic primers, but the polymorphism at population level varied greatly, within the range of 59.6%-93.2%. The genetic differentiation index (G(st)) between the populations based on Nei's genetic heterogenesis analysis was 0.3365, and the gene flow (N(m)) was 0.4931. The genetic differentiation between the populations was lower than that within the populations, suggesting that the genetic variation of I. farinosa mainly come from the interior of the populations. The UPGMA clustering based on the genetic similarities between the isolates revealed that the Xishan population was monophylectic, while the other five populations were polyphylectic, with the Yaoluoping population being the most heterogenic and the Langyashan population being the least heterogenic. No correlations were observed between the geographic distance and the genetic distance of the populations. According to the UPGMA clustering based on the genetic distance between the populations, the six populations were classified into three groups, and this classification was accorded with the clustering based on geographic environment, suggesting the effects of environmental heterogeneity on the population heterogeneity.

A systematic review of economic evaluations of population-based sodium reduction interventions

PubMed Central

Hope, Silvia F.; Webster, Jacqui; Trieu, Kathy; Pillay, Arti; Ieremia, Merina; Bell, Colin; Snowdon, Wendy; Neal, Bruce; Moodie, Marj

2017-01-01

Objective To summarise evidence describing the cost-effectiveness of population-based interventions targeting sodium reduction. Methods A systematic search of published and grey literature databases and websites was conducted using specified key words. Characteristics of identified economic evaluations were recorded, and included studies were appraised for reporting quality using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklist. Results Twenty studies met the study inclusion criteria and received a full paper review. Fourteen studies were identified as full economic evaluations in that they included both costs and benefits associated with an intervention measured against a comparator. Most studies were modelling exercises based on scenarios for achieving salt reduction and assumed effects on health outcomes. All 14 studies concluded that their specified intervention(s) targeting reductions in population sodium consumption were cost-effective, and in the majority of cases, were cost saving. Just over half the studies (8/14) were assessed as being of ‘excellent’ reporting quality, five studies fell into the ‘very good’ quality category and one into the ‘good’ category. All of the identified evaluations were based on modelling, whereby inputs for all the key parameters including the effect size were either drawn from published datasets, existing literature or based on expert advice. Conclusion Despite a clear increase in evaluations of salt reduction programs in recent years, this review identified relatively few economic evaluations of population salt reduction interventions. None of the studies were based on actual implementation of intervention(s) and the associated collection of new empirical data. The studies universally showed that population-based salt reduction strategies are likely to be cost effective or cost saving. However, given the reliance on modelling, there is a need for the effectiveness of new interventions to be evaluated in the field using strong study designs and parallel economic evaluations. PMID:28355231

Prostate-Specific Antigen (PSA)–Based Population Screening for Prostate Cancer: An Economic Analysis

PubMed Central

Tawfik, A

2015-01-01

Background The prostate-specific antigen (PSA) blood test has become widely used in Canada to test for prostate cancer (PC), the most common cancer among Canadian men. Data suggest that population-based PSA screening may not improve overall survival. Objectives This analysis aimed to review existing economic evaluations of population-based PSA screening, determine current spending on opportunistic PSA screening in Ontario, and estimate the cost of introducing a population-based PSA screening program in the province. Methods A systematic literature search was performed to identify economic evaluations of population-based PSA screening strategies published from 1998 to 2013. Studies were assessed for their methodological quality and applicability to the Ontario setting. An original cost analysis was also performed, using data from Ontario administrative sources and from the published literature. One-year costs were estimated for 4 strategies: no screening, current (opportunistic) screening of men aged 40 years and older, current (opportunistic) screening of men aged 50 to 74 years, and population-based screening of men aged 50 to 74 years. The analysis was conducted from the payer perspective. Results The literature review demonstrated that, overall, population-based PSA screening is costly and cost-ineffective but may be cost-effective in specific populations. Only 1 Canadian study, published 15 years ago, was identified. Approximately $119.2 million is being spent annually on PSA screening of men aged 40 years and older in Ontario, including close to $22 million to screen men younger than 50 and older than 74 years of age (i.e., outside the target age range for a population-based program). A population-based screening program in Ontario would cost approximately $149.4 million in the first year. Limitations Estimates were based on the synthesis of data from a variety of sources, requiring several assumptions and causing uncertainty in the results. For example, where Ontario-specific data were unavailable, data from the United States were used. Conclusions PSA screening is associated with significant costs to the health care system when the cost of the PSA test itself is considered in addition to the costs of diagnosis, staging, and treatment of screen-detected PCs. PMID:26366237

An agent-based computational model for tuberculosis spreading on age-structured populations

NASA Astrophysics Data System (ADS)

Graciani Rodrigues, C. C.; Espíndola, Aquino L.; Penna, T. J. P.

2015-06-01

In this work we present an agent-based computational model to study the spreading of the tuberculosis (TB) disease on age-structured populations. The model proposed is a merge of two previous models: an agent-based computational model for the spreading of tuberculosis and a bit-string model for biological aging. The combination of TB with the population aging, reproduces the coexistence of health states, as seen in real populations. In addition, the universal exponential behavior of mortalities curves is still preserved. Finally, the population distribution as function of age shows the prevalence of TB mostly in elders, for high efficacy treatments.

Locating helicopter emergency medical service bases to optimise population coverage versus average response time.

PubMed

Garner, Alan A; van den Berg, Pieter L

2017-10-16

New South Wales (NSW), Australia has a network of multirole retrieval physician staffed helicopter emergency medical services (HEMS) with seven bases servicing a jurisdiction with population concentrated along the eastern seaboard. The aim of this study was to estimate optimal HEMS base locations within NSW using advanced mathematical modelling techniques. We used high resolution census population data for NSW from 2011 which divides the state into areas containing 200-800 people. Optimal HEMS base locations were estimated using the maximal covering location problem facility location optimization model and the average response time model, exploring the number of bases needed to cover various fractions of the population for a 45 min response time threshold or minimizing the overall average response time to all persons, both in green field scenarios and conditioning on the current base structure. We also developed a hybrid mathematical model where average response time was optimised based on minimum population coverage thresholds. Seven bases could cover 98% of the population within 45mins when optimised for coverage or reach the entire population of the state within an average of 21mins if optimised for response time. Given the existing bases, adding two bases could either increase the 45 min coverage from 91% to 97% or decrease the average response time from 21mins to 19mins. Adding a single specialist prehospital rapid response HEMS to the area of greatest population concentration decreased the average state wide response time by 4mins. The optimum seven base hybrid model that was able to cover 97.75% of the population within 45mins, and all of the population in an average response time of 18 mins included the rapid response HEMS model. HEMS base locations can be optimised based on either percentage of the population covered, or average response time to the entire population. We have also demonstrated a hybrid technique that optimizes response time for a given number of bases and minimum defined threshold of population coverage. Addition of specialized rapid response HEMS services to a system of multirole retrieval HEMS may reduce overall average response times by improving access in large urban areas.

Hippocampal atrophy in people with memory deficits: results from the population-based IPREA study.

PubMed

Ferrarini, Luca; van Lew, Baldur; Reiber, Johan H C; Gandin, Claudia; Galluzzo, Lucia; Scafato, Emanuele; Frisoni, Giovanni B; Milles, Julien; Pievani, Michela

2014-07-01

Clinical studies have shown that hippocampal atrophy is present before dementia in people with memory deficits and can predict dementia development. The question remains whether this association holds in the general population. This is of interest for the possible use of hippocampal atrophy to screen population for preventive interventions. The aim of this study was to assess hippocampal volume and shape abnormalities in elderly adults with memory deficits in a cross-sectional population-based study. We included individuals participating in the Italian Project on the Epidemiology of Alzheimer Disease (IPREA) study: 75 cognitively normal individuals (HC), 31 individuals with memory deficits (MEM), and 31 individuals with memory deficits not otherwise specified (MEMnos). Hippocampal volumes and shape were extracted through manual tracing and the growing and adaptive meshes (GAMEs) shape-modeling algorithm. We investigated between-group differences in hippocampal volume and shape, and correlations with memory deficits. In MEM participants, hippocampal volumes were significantly smaller than in HC and were mildly associated with worse memory scores. Memory-associated shape changes mapped to the anterior hippocampus. Shape-based analysis detected no significant difference between MEM and HC, while MEMnos showed shape changes in the posterior hippocampus compared with HC and MEM groups. These findings support the discriminant validity of hippocampal volumetry as a biomarker of memory impairment in the general population. The detection of shape changes in MEMnos but not in MEM participants suggests that shape-based biomarkers might lack sensitivity to detect Alzheimer's-like pathology in the general population.

What interventions increase commuter cycling? A systematic review.

PubMed

Stewart, Glenn; Anokye, Nana Kwame; Pokhrel, Subhash

2015-08-14

To identify interventions that will increase commuter cycling. All settings where commuter cycling might take place. Adults (aged 18+) in any country. Individual, group or environmental interventions including policies and infrastructure. A wide range of 'changes in commuter cycling' indicators, including frequency of cycling, change in workforce commuting mode, change in commuting population transport mode, use of infrastructure by defined populations and population modal shift. 12 studies from 6 countries (6 from the UK, 2 from Australia, 1 each from Sweden, Ireland, New Zealand and the USA) met the inclusion criteria. Of those, 2 studies were randomised control trials and the remainder preintervention and postintervention studies. The majority of studies (n=7) evaluated individual-based or group-based interventions and the rest environmental interventions. Individual-based or group-based interventions in 6/7 studies were found to increase commuter cycling of which the effect was significant in only 3/6 studies. Environmental interventions, however, had small but positive effects in much larger but more difficult to define populations. Almost all studies had substantial loss to follow-up. Despite commuter cycling prevalence varying widely between countries, robust evidence of what interventions will increase commuter cycling in low cycling prevalence nations is sparse. Wider environmental interventions that make cycling conducive appear to reach out to hard to define but larger populations. This could mean that environmental interventions, despite their small positive effects, have greater public health significance than individual-based or group-based measures because those interventions encourage a larger number of people to integrate physical activity into their everyday lives. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Prevalence and causes of hearing impairment in Africa.

PubMed

Mulwafu, W; Kuper, H; Ensink, R J H

2016-02-01

To systematically assess the data on the prevalence and causes of hearing impairment in Africa. Systematic review on the prevalence and causes of hearing loss in Africa. We undertook a literature search of seven electronic databases (EMBASE, PubMed, Medline, Global Health, Web of Knowledge, Academic Search Complete and Africa Wide Information) and manually searched bibliographies of included articles. The search was restricted to population-based studies on hearing impairment in Africa. Data were extracted using a standard protocol. We identified 232 articles and included 28 articles in the final analysis. The most common cut-offs used for hearing impairment were 25 and 30 dB HL, but this ranged between 15 and 40 dB HL. For a cut-off of 25 dB, the median was 7.7% for the children- or school-based studies and 17% for population-based studies. For a cut-off of 30 dB HL, the median was 6.6% for the children or school-based studies and 31% for population-based studies. In schools for the deaf, the most common cause of hearing impairment was cryptogenic deafness (50%) followed by infectious causes (43%). In mainstream schools and general population, the most common cause of hearing impairment was middle ear disease (36%), followed by undetermined causes (35%) and cerumen impaction (24%). There are very few population-based studies available to estimate the prevalence of hearing impairment in Africa. Those studies that are available use different cut-offs, making comparison difficult. However, the evidence suggests that the prevalence of hearing impairment is high and that much of it is avoidable or treatable. © 2015 John Wiley & Sons Ltd.

Self-reported indications for antidepressant use in a population-based cohort of middle-aged and elderly.

PubMed

Aarts, Nikkie; Noordam, Raymond; Hofman, Albert; Tiemeier, Henning; Stricker, Bruno H; Visser, Loes E

2016-10-01

Background Population-based studies investigating indications for antidepressant prescribing mostly rely on diagnoses from general practitioners. However, diagnostic codes might be incomplete and drugs may be prescribed 'off-label' for indications not investigated in clinical trials. Objective We aimed to study indications for antidepressant use based on self-report. Also, we studied the presence of depressive symptoms associated with the self-reported indications. Setting Our study population of antidepressant users was selected based on interview data between 1997 and 2013 from the prospective population-based Rotterdam Study cohort (age >45 years). Method Antidepressant use, self-reported indication for use, and presence of depressive symptoms (Center for Epidemiological Studies Depression Scale) were based on interview. Self-reported indications were categorized by the researchers into officially approved, clinically-accepted and commonly mentioned off-label indications. Main outcome measures A score of 16 and higher on the Center for Epidemiological Studies Depression Scale was considered as indicator for clinically-relevant depressive symptoms. Results The majority of 914 antidepressant users reported 'depression' (52.4 %) as indication for treatment. Furthermore, anxiety, stress and sleep disorders were reported in selective serotonin reuptake inhibitor and other antidepressant users (ranging from 5.9 to 13.3 %). The indication 'pain' was commonly mentioned by tricyclic antidepressant users (19.0 %). Indications were statistically significantly associated with higher depressive symptom scores when compared to non-users (n = 10,979). Conclusions Depression was the main indication for antidepressant treatment. However, our findings suggest that antidepressants are also used for off-label indications, subthreshold disorders and complex situations, which were all associated with clinically-relevant depressive symptoms in the middle-aged and elderly population.

What interventions increase commuter cycling? A systematic review

PubMed Central

Stewart, Glenn; Anokye, Nana Kwame; Pokhrel, Subhash

2015-01-01

Objective To identify interventions that will increase commuter cycling. Setting All settings where commuter cycling might take place. Participants Adults (aged 18+) in any country. Interventions Individual, group or environmental interventions including policies and infrastructure. Primary and secondary outcome measures A wide range of ‘changes in commuter cycling’ indicators, including frequency of cycling, change in workforce commuting mode, change in commuting population transport mode, use of infrastructure by defined populations and population modal shift. Results 12 studies from 6 countries (6 from the UK, 2 from Australia, 1 each from Sweden, Ireland, New Zealand and the USA) met the inclusion criteria. Of those, 2 studies were randomised control trials and the remainder preintervention and postintervention studies. The majority of studies (n=7) evaluated individual-based or group-based interventions and the rest environmental interventions. Individual-based or group-based interventions in 6/7 studies were found to increase commuter cycling of which the effect was significant in only 3/6 studies. Environmental interventions, however, had small but positive effects in much larger but more difficult to define populations. Almost all studies had substantial loss to follow-up. Conclusions Despite commuter cycling prevalence varying widely between countries, robust evidence of what interventions will increase commuter cycling in low cycling prevalence nations is sparse. Wider environmental interventions that make cycling conducive appear to reach out to hard to define but larger populations. This could mean that environmental interventions, despite their small positive effects, have greater public health significance than individual-based or group-based measures because those interventions encourage a larger number of people to integrate physical activity into their everyday lives. PMID:26275902

Acute myeloid leukemia in the real world: why population-based registries are needed

PubMed Central

Lazarevic, Vladimir; Hörstedt, Ann-Sofi; Hagberg, Oskar; Höglund, Martin

2012-01-01

Population-based registries may provide data complementary to that from basic science and clinical intervention studies, all of which are essential for establishing recommendations for the management of patients in the real world. The same quality criteria apply for the evidence-based label, and both high representation and good data quality are crucial in registry studies. Registries with high coverage of the target population reduce the impact of selection on outcome and the subsequent problem with extrapolating data to nonstudied populations. Thus, data useful for clinical decision in situations not well covered by clinical studies can be provided. The potential clinical impact of data from population-based studies is exemplified with analyses from the Swedish Acute Leukemia Registry containing more than 3300 acute myeloid leukemia (AML) patients diagnosed between 1997 and 2006 with a median follow-up of 6.2 years on (1) the role of intensive combination chemotherapy for older patients with AML, (2) the impact of allogeneic stem cell transplantation on survival of younger patients with AML, and (3) the continuing problem with early deaths in acute promyelocytic leukemia. We also present the first Web-based dynamic graph showing the complex interaction between age, performance status, the proportion of patients given intensive treatment, early death rate, complete remission rate, use of allogeneic transplants, and overall survival in AML (non-AML). PMID:22383796

Acute myeloid leukemia in the real world: why population-based registries are needed.

PubMed

Juliusson, Gunnar; Lazarevic, Vladimir; Hörstedt, Ann-Sofi; Hagberg, Oskar; Höglund, Martin

2012-04-26

Population-based registries may provide data complementary to that from basic science and clinical intervention studies, all of which are essential for establishing recommendations for the management of patients in the real world. The same quality criteria apply for the evidence-based label, and both high representation and good data quality are crucial in registry studies. Registries with high coverage of the target population reduce the impact of selection on outcome and the subsequent problem with extrapolating data to nonstudied populations. Thus, data useful for clinical decision in situations not well covered by clinical studies can be provided. The potential clinical impact of data from population-based studies is exemplified with analyses from the Swedish Acute Leukemia Registry containing more than 3300 acute myeloid leukemia (AML) patients diagnosed between 1997 and 2006 with a median follow-up of 6.2 years on (1) the role of intensive combination chemotherapy for older patients with AML, (2) the impact of allogeneic stem cell transplantation on survival of younger patients with AML, and (3) the continuing problem with early deaths in acute promyelocytic leukemia. We also present the first Web-based dynamic graph showing the complex interaction between age, performance status, the proportion of patients given intensive treatment, early death rate, complete remission rate, use of allogeneic transplants, and overall survival in AML (non-AML).

[Frailty in Germany: status and perspectives : Results from a workshop of the German Society for Epidemiology].

PubMed

Fuchs, Judith; Scheidt-Nave, Christa; Gaertner, Beate; Dapp, Ulrike; von Renteln-Kruse, Wolfgang; Saum, Kai-Uwe; Thorand, Barbara; Strobl, Ralf; Grill, Eva

2016-12-01

A standardized, valid and comparable operationalization and assessment of frailty in population-based studies is essential in order to describe the prevalence and determinants of frailty in the population. After an introduction to the subject the main goal of a workshop at the 9th annual meeting of the German Society for Epidemiology (DGEpi) was to present approaches and results from four different studies in Germany. The following four population-based studies were used to describe frailty in Germany: the German health interview and examination survey for adults (DEGS1), the epidemiological study on the chances of prevention, early recognition and optimized treatment of chronic diseases in the older population (ESTHER), the cooperative health research in the region Augsburg (KORA Age) study and the longitudinal urban cohort ageing study (LUCAS) in Hamburg. The four studies consistently showed that frailty is widespread in older and oldest-old persons in Germany. It is obvious that frailty represents a relevant concept in Germany even if there is currently no uniform basis for operationalization. Concepts and instruments for the collation of frailty should be included in future population-based studies in order to make a better assessment of older people's health situation and to describe the unused potential for prevention in an aging society.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kostova, T; Carlsen, T

We present a study, based on simulations with SERDYCA, a spatially-explicit individual based model of rodent dynamics, on the connection between population persistence and the presence of inhomogeneities in the habitat. We are specifically interested on the effect that inhomogeneities that do not fragment the environment, have on population persistence. Our results suggest that a certain percentage of inhomogeneities can increase the average time to extinction of the population. Inhomogeneities decrease the population density and can increase the ratio of juveniles in the population thus providing a better chance for the population to restore itself after a severe period withmore » critically low population density. We call this the ''inhomogeneity localization effect''.« less

Epilepsy Among Children and Adolescents with Autism Spectrum Disorders: A Population-Based Study

ERIC Educational Resources Information Center

Jokiranta, Elina; Sourander, Andre; Suominen, Auli; Timonen-Soivio, Laura; Brown, Alan S.; Sillanpää, Matti

2014-01-01

The present population-based study examines associations between epilepsy and autism spectrum disorders (ASD). The cohort includes register data of 4,705 children born between 1987 and 2005 and diagnosed as cases of childhood autism, Asperger's syndrome or pervasive developmental disorders--not otherwise specified. Each case was matched to four…

Analysis of population structure and genetic history of cattle breeds based on high-density SNP data

USDA-ARS?s Scientific Manuscript database

Advances in single nucleotide polymorphism (SNP) genotyping microarrays have facilitated a new understanding of population structure and evolutionary history for several species. Most existing studies in livestock were based on low density SNP arrays. The first wave of low density SNP studies on cat...

Sexual Orientation and School Discipline: New Evidence from a Population-Based Sample

ERIC Educational Resources Information Center

Mittleman, Joel

2018-01-01

Sexual minorities' risk for exclusionary discipline is a commonly cited indicator of the challenges that these students face. The current study addresses this issue by introducing a new data source for research on sexual minority students: the Fragile Families and Childhood Wellbeing Study. In this geographically diverse, population-based sample,…

Sooner Versus Later: Factors Associated with Temporal Sequencing of Suicide

ERIC Educational Resources Information Center

Kaplan, Mark S.; McFarland, Bentson H.; Huguet, Nathalie; Newsom, Jason T.

2006-01-01

There are few (if any) population-based prospective studies that provide information on factors associated with temporal sequencing of suicide. In this prospective population-based study, the National Health Interview Survey (NHIS), 1986-1994, was linked to the National Death Index (NDI), 1986-1997, to assess factors that predict recent (within 12…

RELIANCE ON GEOCODED MATERNAL RESIDENCE: IMPACT ON A POPULATION-BASED CASE-CONTROL STUDY OF AIR QUALITY AND BIRTH DEFECTS

EPA Science Inventory

Introduction: Unbiased geocoding of maternal residence is critical to the success of an ongoing population-based case-control study of exposure to five criteria air pollutants and the risk of selected birth defects in seven Texas counties between 1997 and 2000. The geocoded res...

Accuracy of Predicted Genomic Breeding Values in Purebred and Crossbred Pigs.

PubMed

Hidalgo, André M; Bastiaansen, John W M; Lopes, Marcos S; Harlizius, Barbara; Groenen, Martien A M; de Koning, Dirk-Jan

2015-05-26

Genomic selection has been widely implemented in dairy cattle breeding when the aim is to improve performance of purebred animals. In pigs, however, the final product is a crossbred animal. This may affect the efficiency of methods that are currently implemented for dairy cattle. Therefore, the objective of this study was to determine the accuracy of predicted breeding values in crossbred pigs using purebred genomic and phenotypic data. A second objective was to compare the predictive ability of SNPs when training is done in either single or multiple populations for four traits: age at first insemination (AFI); total number of piglets born (TNB); litter birth weight (LBW); and litter variation (LVR). We performed marker-based and pedigree-based predictions. Within-population predictions for the four traits ranged from 0.21 to 0.72. Multi-population prediction yielded accuracies ranging from 0.18 to 0.67. Predictions across purebred populations as well as predicting genetic merit of crossbreds from their purebred parental lines for AFI performed poorly (not significantly different from zero). In contrast, accuracies of across-population predictions and accuracies of purebred to crossbred predictions for LBW and LVR ranged from 0.08 to 0.31 and 0.11 to 0.31, respectively. Accuracy for TNB was zero for across-population prediction, whereas for purebred to crossbred prediction it ranged from 0.08 to 0.22. In general, marker-based outperformed pedigree-based prediction across populations and traits. However, in some cases pedigree-based prediction performed similarly or outperformed marker-based prediction. There was predictive ability when purebred populations were used to predict crossbred genetic merit using an additive model in the populations studied. AFI was the only exception, indicating that predictive ability depends largely on the genetic correlation between PB and CB performance, which was 0.31 for AFI. Multi-population prediction was no better than within-population prediction for the purebred validation set. Accuracy of prediction was very trait-dependent. Copyright © 2015 Hidalgo et al.

The association between ALS and population density: A population based study.

PubMed

Scott, Kirsten M; Abhinav, Kumar; Wijesekera, Lokesh; Ganesalingam, Jeban; Goldstein, Laura H; Janssen, Anna; Dougherty, Andrew; Willey, Emma; Stanton, Biba R; Turner, Martin R; Ampong, Mary-Ann; Sakel, Mohammed; Orrell, Richard; Howard, Robin; Shaw, Christopher E; Nigel Leigh, P; Al-Chalabi, Ammar

2010-10-01

We aimed to assess whether rural residence is associated with amyotrophic lateral sclerosis in the south-east of England using a population based register. Previous studies in different populations have produced contradictory findings. Residence defined by London borough or non-metropolitan district at time of diagnosis was recorded for each incident case in the South-East England ALS Register between 1995 and 2005. Each of the 26 boroughs or districts of the catchment area of the register was classified according to population density. Age- and sex-adjusted incidence of ALS was calculated for each region and the relationship with population density tested by linear regression, thereby controlling for the underlying population structure. We found that population density in region of residence at diagnosis explained 25% of the variance in ALS rates (r = 0.5, p < 0.01). Thus, in this cohort in the south-east of England, people with ALS were more likely to be resident in areas of high population density at diagnosis.

The association between ALS and population density: A population based study

PubMed Central

SCOTT, KIRSTEN M.; ABHINAV, KUMAR; WIJESEKERA, LOKESH; GANESALINGAM, JEBAN; GOLDSTEIN, LAURA H.; JANSSEN, ANNA; DOUGHERTY, ANDREW; WILLEY, EMMA; STANTON, BIBA R.; TURNER, MARTIN R.; AMPONG, MARY-ANN; SAKEL, MOHAMMED; ORRELL, RICHARD; HOWARD, ROBIN; SHAW, CHRISTOPHER E.; LEIGH, P. NIGEL; AL-CHALABI, AMMAR

2011-01-01

We aimed to assess whether rural residence is associated with amyotrophic lateral sclerosis in the south-east of England using a population based register. Previous studies in different populations have produced contradictory findings. Residence defined by London borough or non-metropolitan district at time of diagnosis was recorded for each incident case in the South-East England ALS Register between 1995 and 2005. Each of the 26 boroughs or districts of the catchment area of the register was classified according to population density. Age- and sex-adjusted incidence of ALS was calculated for each region and the relationship with population density tested by linear regression, thereby controlling for the underlying population structure. We found that population density in region of residence at diagnosis explained 25% of the variance in ALS rates (r = 0.5, p < 0.01). Thus, in this cohort in the south-east of England, people with ALS were more likely to be resident in areas of high population density at diagnosis. PMID:20429684

Caste- and ethnicity-based inequalities in HIV/AIDS-related knowledge gap: a case of Nepal.

PubMed

Atteraya, Madhu; Kimm, HeeJin; Song, In Han

2015-05-01

Caste- and ethnicity-based inequalities are major obstacles to achieving health equity. The authors investigated whether there is any association between caste- and ethnicity-based inequalities and HIV-related knowledge within caste and ethnic populations. They used the 2011 Nepal Demographic and Health Survey, a nationally represented cross-sectional study data set. The study sample consisted of 11,273 women between 15 and 49 years of age. Univariate and logistic regression models were used to examine the relationship between caste- and ethnicity-based inequalities and HIV-related knowledge. The study sample was divided into high Hindu caste (47.9 percent), "untouchable" caste (18.4 percent), and indigenous populations (33.7 percent). Within the study sample, the high-caste population was found to have the greatest knowledge of the means by which HIV is prevented and transmitted. After controlling for socioeconomic and demographic characteristics, untouchables were the least knowledgeable. The odds ratio for incomplete knowledge about transmission among indigenous populations was 1.27 times higher than that for high Hindu castes, but there was no significant difference in knowledge of preventive measures. The findings suggest the existence of a prevailing HIV knowledge gap. This in turn suggests that appropriate steps need to be implemented to convey complete knowledge to underprivileged populations.

Comparison between Flow Cytometry and Traditional Culture Methods for Efficacy Assessment of Six Disinfectant Agents against Nosocomial Bacterial Species

PubMed Central

Massicotte, Richard; Mafu, Akier A.; Ahmad, Darakhshan; Deshaies, Francis; Pichette, Gilbert; Belhumeur, Pierre

2017-01-01

The present study was undertaken to compare the use of flow cytometry (FCM) and traditional culture methods for efficacy assessment of six disinfectants used in Quebec hospitals including: two quaternary ammonium-based, two activated hydrogen peroxide-based, one phenol-based, and one sodium hypochlorite-based. Four nosocomial bacterial species, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Vancomycin-resistant Enterococci faecalis, were exposed to minimum lethal concentrations (MLCs) and sublethal concentrations (1/2 MLCs) of disinfectants under study. The results showed a strong correlation between the two techniques for the presence of dead and live cell populations, as well as, evidence of injured populations with the FCM. The only exception was observed with sodium hypochlorite at higher concentrations where fluorescence was diminished and underestimating dead cell population. The results also showed that FCM can replace traditional microbiological methods to study disinfectant efficacy on bacteria. Furthermore, FCM profiles for E. coli and E. faecalis cells exposed to sublethal concentrations exhibited distinct populations of injured cells, opening a new aspect for future research and investigation to elucidate the role of injured, cultural/noncuturable/resuscitable cell populations in infection control. PMID:28217115

Methods for estimating population density in data-limited areas: evaluating regression and tree-based models in Peru.

PubMed

Anderson, Weston; Guikema, Seth; Zaitchik, Ben; Pan, William

2014-01-01

Obtaining accurate small area estimates of population is essential for policy and health planning but is often difficult in countries with limited data. In lieu of available population data, small area estimate models draw information from previous time periods or from similar areas. This study focuses on model-based methods for estimating population when no direct samples are available in the area of interest. To explore the efficacy of tree-based models for estimating population density, we compare six different model structures including Random Forest and Bayesian Additive Regression Trees. Results demonstrate that without information from prior time periods, non-parametric tree-based models produced more accurate predictions than did conventional regression methods. Improving estimates of population density in non-sampled areas is important for regions with incomplete census data and has implications for economic, health and development policies.

Methods for Estimating Population Density in Data-Limited Areas: Evaluating Regression and Tree-Based Models in Peru

PubMed Central

Anderson, Weston; Guikema, Seth; Zaitchik, Ben; Pan, William

2014-01-01

Obtaining accurate small area estimates of population is essential for policy and health planning but is often difficult in countries with limited data. In lieu of available population data, small area estimate models draw information from previous time periods or from similar areas. This study focuses on model-based methods for estimating population when no direct samples are available in the area of interest. To explore the efficacy of tree-based models for estimating population density, we compare six different model structures including Random Forest and Bayesian Additive Regression Trees. Results demonstrate that without information from prior time periods, non-parametric tree-based models produced more accurate predictions than did conventional regression methods. Improving estimates of population density in non-sampled areas is important for regions with incomplete census data and has implications for economic, health and development policies. PMID:24992657

Genetic affinities of north and northeastern populations of India: inference from HLA-based study.

PubMed

Agrawal, S; Srivastava, S K; Borkar, M; Chaudhuri, T K

2008-08-01

India is like a microcosm of the world in terms of its diversity; religion, climate and ethnicity which leads to genetic variations in the populations. As a highly polymorphic marker, the human leukocyte antigen (HLA) system plays an important role in the genetic differentiation studies. To assess the genetic diversity of HLA class II loci, we studied a total of 1336 individuals from north India using DNA-based techniques. The study included four endogamous castes (Kayastha, Mathurs, Rastogies and Vaishyas), two inbreeding Muslim populations (Shias and Sunnis) from north India and three northeast Indian populations (Lachung, Mech and Rajbanshi). A total of 36 alleles were observed at DRB1 locus in both Hindu castes and Muslims from north, while 21 alleles were seen in northeast Indians. At the DQA1 locus, the number of alleles ranged from 11 to 17 in the studied populations. The total number of alleles at DQB1 was 19, 12 and 20 in the studied castes, Muslims and northeastern populations, respectively. The most frequent haplotypes observed in all the studied populations were DRB1*0701-DQA1*0201-DQB1*0201 and DRB1*1501-DQA1*0103-DQB1*0601. Upon comparing our results with other world populations, we observed the presence of Caucasoid element in north Indian population. However, differential admixturing among Sunnis and Shias with the other north Indians was evident. Northeastern populations showed genetic affinity with Mongoloids from southeast Asia. When genetic distances were calculated, we found the north Indians and northeastern populations to be markedly unrelated.

Emergence of cytotoxic resistance in cancer cell populations: Single-cell mechanisms and population-level consequences

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lorenzi, Tommaso; Chisholm, Rebecca H.; Lorz, Alexander

We formulate an individual-based model and a population model of phenotypic evolution, under cytotoxic drugs, in a cancer cell population structured by the expression levels of survival-potential and proliferation-potential. We apply these models to a recently studied experimental system. Our results suggest that mechanisms based on fundamental laws of biology can reversibly push an actively-proliferating, and drug-sensitive, cell population to transition into a weakly-proliferative and drug-tolerant state, which will eventually facilitate the emergence of more potent, proliferating and drug-tolerant cells.

Comparing population and incident data for optimal air ambulance base locations in Norway.

PubMed

Røislien, Jo; van den Berg, Pieter L; Lindner, Thomas; Zakariassen, Erik; Uleberg, Oddvar; Aardal, Karen; van Essen, J Theresia

2018-05-24

Helicopter emergency medical services are important in many health care systems. Norway has a nationwide physician manned air ambulance service servicing a country with large geographical variations in population density and incident frequencies. The aim of the study was to compare optimal air ambulance base locations using both population and incident data. We used municipality population and incident data for Norway from 2015. The 428 municipalities had a median (5-95 percentile) of 4675 (940-36,264) inhabitants and 10 (2-38) incidents. Optimal helicopter base locations were estimated using the Maximal Covering Location Problem (MCLP) optimization model, exploring the number and location of bases needed to cover various fractions of the population for time thresholds 30 and 45 min, in green field scenarios and conditioned on the existing base structure. The existing bases covered 96.90% of the population and 91.86% of the incidents for time threshold 45 min. Correlation between municipality population and incident frequencies was -0.0027, and optimal base locations varied markedly between the two data types, particularly when lowering the target time. The optimal solution using population density data put focus on the greater Oslo area, where one third of Norwegians live, while using incident data put focus on low population high incident areas, such as northern Norway and winter sport resorts. Using population density data as a proxy for incident frequency is not recommended, as the two data types lead to different optimal base locations. Lowering the target time increases the sensitivity to choice of data.

Variation in the cranial base orientation and facial skeleton in dry skulls sampled from three major populations.

PubMed

Kuroe, Kazuto; Rosas, Antonio; Molleson, Theya

2004-04-01

The aim of this study was to analyse the effects of cranial base orientation on the morphology of the craniofacial system in human populations. Three geographically distant populations from Europe (72), Africa (48) and Asia (24) were chosen. Five angular and two linear variables from the cranial base component and six angular and six linear variables from the facial component based on two reference lines of the vertical posterior maxillary and Frankfort horizontal planes were measured. The European sample presented dolichofacial individuals with a larger face height and a smaller face depth derived from a raised cranial base and facial cranium orientation which tended to be similar to the Asian sample. The African sample presented brachyfacial individuals with a reduced face height and a larger face depth as a result of a lowered cranial base and facial cranium orientation. The Asian sample presented dolichofacial individuals with a larger face height and depth due to a raised cranial base and facial cranium orientation. The findings of this study suggest that cranial base orientation and posterior cranial base length appear to be valid discriminating factors between different human populations.

Combination of graph heuristics in producing initial solution of curriculum based course timetabling problem

NASA Astrophysics Data System (ADS)

Wahid, Juliana; Hussin, Naimah Mohd

2016-08-01

The construction of population of initial solution is a crucial task in population-based metaheuristic approach for solving curriculum-based university course timetabling problem because it can affect the convergence speed and also the quality of the final solution. This paper presents an exploration on combination of graph heuristics in construction approach in curriculum based course timetabling problem to produce a population of initial solutions. The graph heuristics were set as single and combination of two heuristics. In addition, several ways of assigning courses into room and timeslot are implemented. All settings of heuristics are then tested on the same curriculum based course timetabling problem instances and are compared with each other in terms of number of population produced. The result shows that combination of saturation degree followed by largest degree heuristic produce the highest number of population of initial solutions. The results from this study can be used in the improvement phase of algorithm that uses population of initial solutions.

Agent-based modeling of the spread of the 1918-1919 flu in three Canadian fur trading communities.

PubMed

O'Neil, Caroline A; Sattenspiel, Lisa

2010-01-01

Previous attempts to study the 1918-1919 flu in three small communities in central Manitoba have used both three-community population-based and single-community agent-based models. These studies identified critical factors influencing epidemic spread, but they also left important questions unanswered. The objective of this project was to design a more realistic agent-based model that would overcome limitations of earlier models and provide new insights into these outstanding questions. The new model extends the previous agent-based model to three communities so that results can be compared to those from the population-based model. Sensitivity testing was conducted, and the new model was used to investigate the influence of seasonal settlement and mobility patterns, the geographic heterogeneity of the observed 1918-1919 epidemic in Manitoba, and other questions addressed previously. Results confirm outcomes from the population-based model that suggest that (a) social organization and mobility strongly influence the timing and severity of epidemics and (b) the impact of the epidemic would have been greater if it had arrived in the summer rather than the winter. New insights from the model suggest that the observed heterogeneity among communities in epidemic impact was not unusual and would have been the expected outcome given settlement structure and levels of interaction among communities. Application of an agent-based computer simulation has helped to better explain observed patterns of spread of the 1918-1919 flu epidemic in central Manitoba. Contrasts between agent-based and population-based models illustrate the advantages of agent-based models for the study of small populations. © 2010 Wiley-Liss, Inc.

The Case for Diabetes Population Health Improvement: Evidence-Based Programming for Population Outcomes in Diabetes.

PubMed

Golden, Sherita Hill; Maruthur, Nisa; Mathioudakis, Nestoras; Spanakis, Elias; Rubin, Daniel; Zilbermint, Mihail; Hill-Briggs, Felicia

2017-07-01

The goal of this review is to describe diabetes within a population health improvement framework and to review the evidence for a diabetes population health continuum of intervention approaches, including diabetes prevention and chronic and acute diabetes management, to improve clinical and economic outcomes. Recent studies have shown that compared to usual care, lifestyle interventions in prediabetes lower diabetes risk at the population-level and that group-based programs have low incremental medial cost effectiveness ratio for health systems. Effective outpatient interventions that improve diabetes control and process outcomes are multi-level, targeting the patient, provider, and healthcare system simultaneously and integrate community health workers as a liaison between the patient and community-based healthcare resources. A multi-faceted approach to diabetes management is also effective in the inpatient setting. Interventions shown to promote safe and effective glycemic control and use of evidence-based glucose management practices include provider reminder and clinical decision support systems, automated computer order entry, provider education, and organizational change. Future studies should examine the cost-effectiveness of multi-faceted outpatient and inpatient diabetes management programs to determine the best financial models for incorporating them into diabetes population health strategies.

Generalization and dilution of association results from European GWAS in populations of non-European ancestry: the PAGE study.

PubMed

Carlson, Christopher S; Matise, Tara C; North, Kari E; Haiman, Christopher A; Fesinmeyer, Megan D; Buyske, Steven; Schumacher, Fredrick R; Peters, Ulrike; Franceschini, Nora; Ritchie, Marylyn D; Duggan, David J; Spencer, Kylee L; Dumitrescu, Logan; Eaton, Charles B; Thomas, Fridtjof; Young, Alicia; Carty, Cara; Heiss, Gerardo; Le Marchand, Loic; Crawford, Dana C; Hindorff, Lucia A; Kooperberg, Charles L

2013-09-01

The vast majority of genome-wide association study (GWAS) findings reported to date are from populations with European Ancestry (EA), and it is not yet clear how broadly the genetic associations described will generalize to populations of diverse ancestry. The Population Architecture Using Genomics and Epidemiology (PAGE) study is a consortium of multi-ancestry, population-based studies formed with the objective of refining our understanding of the genetic architecture of common traits emerging from GWAS. In the present analysis of five common diseases and traits, including body mass index, type 2 diabetes, and lipid levels, we compare direction and magnitude of effects for GWAS-identified variants in multiple non-EA populations against EA findings. We demonstrate that, in all populations analyzed, a significant majority of GWAS-identified variants have allelic associations in the same direction as in EA, with none showing a statistically significant effect in the opposite direction, after adjustment for multiple testing. However, 25% of tagSNPs identified in EA GWAS have significantly different effect sizes in at least one non-EA population, and these differential effects were most frequent in African Americans where all differential effects were diluted toward the null. We demonstrate that differential LD between tagSNPs and functional variants within populations contributes significantly to dilute effect sizes in this population. Although most variants identified from GWAS in EA populations generalize to all non-EA populations assessed, genetic models derived from GWAS findings in EA may generate spurious results in non-EA populations due to differential effect sizes. Regardless of the origin of the differential effects, caution should be exercised in applying any genetic risk prediction model based on tagSNPs outside of the ancestry group in which it was derived. Models based directly on functional variation may generalize more robustly, but the identification of functional variants remains challenging.

Generalization and Dilution of Association Results from European GWAS in Populations of Non-European Ancestry: The PAGE Study

PubMed Central

Carlson, Christopher S.; Matise, Tara C.; North, Kari E.; Haiman, Christopher A.; Fesinmeyer, Megan D.; Buyske, Steven; Schumacher, Fredrick R.; Peters, Ulrike; Franceschini, Nora; Ritchie, Marylyn D.; Duggan, David J.; Spencer, Kylee L.; Dumitrescu, Logan; Eaton, Charles B.; Thomas, Fridtjof; Young, Alicia; Carty, Cara; Heiss, Gerardo; Le Marchand, Loic; Crawford, Dana C.; Hindorff, Lucia A.; Kooperberg, Charles L.

2013-01-01

The vast majority of genome-wide association study (GWAS) findings reported to date are from populations with European Ancestry (EA), and it is not yet clear how broadly the genetic associations described will generalize to populations of diverse ancestry. The Population Architecture Using Genomics and Epidemiology (PAGE) study is a consortium of multi-ancestry, population-based studies formed with the objective of refining our understanding of the genetic architecture of common traits emerging from GWAS. In the present analysis of five common diseases and traits, including body mass index, type 2 diabetes, and lipid levels, we compare direction and magnitude of effects for GWAS-identified variants in multiple non-EA populations against EA findings. We demonstrate that, in all populations analyzed, a significant majority of GWAS-identified variants have allelic associations in the same direction as in EA, with none showing a statistically significant effect in the opposite direction, after adjustment for multiple testing. However, 25% of tagSNPs identified in EA GWAS have significantly different effect sizes in at least one non-EA population, and these differential effects were most frequent in African Americans where all differential effects were diluted toward the null. We demonstrate that differential LD between tagSNPs and functional variants within populations contributes significantly to dilute effect sizes in this population. Although most variants identified from GWAS in EA populations generalize to all non-EA populations assessed, genetic models derived from GWAS findings in EA may generate spurious results in non-EA populations due to differential effect sizes. Regardless of the origin of the differential effects, caution should be exercised in applying any genetic risk prediction model based on tagSNPs outside of the ancestry group in which it was derived. Models based directly on functional variation may generalize more robustly, but the identification of functional variants remains challenging. PMID:24068893

Challenges to be overcome using population-based sampling methods to recruit veterans for a study of post-traumatic stress disorder and traumatic brain injury.

PubMed

Bayley, Peter J; Kong, Jennifer Y; Helmer, Drew A; Schneiderman, Aaron; Roselli, Lauren A; Rosse, Stephanie M; Jackson, Jordan A; Baldwin, Janet; Isaac, Linda; Nolasco, Michael; Blackman, Marc R; Reinhard, Matthew J; Ashford, John Wesson; Chapman, Julie C

2014-04-08

Many investigators are interested in recruiting veterans from recent conflicts in Afghanistan and Iraq with Traumatic Brain Injury (TBI) and/or Post Traumatic Stress Disorder (PTSD). Researchers pursuing such studies may experience problems in recruiting sufficient numbers unless effective strategies are used. Currently, there is very little information on recruitment strategies for individuals with TBI and/or PTSD. It is known that groups of patients with medical conditions may be less likely to volunteer for clinical research. This study investigated the feasibility of recruiting veterans returning from recent military conflicts--Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF)--using a population-based sampling method. Individuals were sampled from a previous epidemiological study. Three study sites focused on recruiting survey respondents (n = 445) who lived within a 60 mile radius of one of the sites. Overall, the successful recruitment of veterans using a population-based sampling method was dependent on the ability to contact potential participants following mass mailing. Study enrollment of participants with probable TBI and/or PTSD had a recruitment yield (enrolled/total identified) of 5.4%. We were able to contact 146 individuals, representing a contact rate of 33%. Sixty-six of the individuals contacted were screened. The major reasons for not screening included a stated lack of interest in the study (n = 37), a failure to answer screening calls after initial contact (n = 30), and an unwillingness or inability to travel to a study site (n = 10). Based on the phone screening, 36 veterans were eligible for the study. Twenty-four veterans were enrolled, (recruitment yield = 5.4%) and twelve were not enrolled for a variety of reasons. Our experience with a population-based sampling method for recruitment of recent combat veterans illustrates the challenges encountered, particularly contacting and screening potential participants. The screening and enrollment data will help guide recruitment for future studies using population-based methods.

Breast and ovarian cancer risks to carriers of the BRCA1 5382insC and 185delAG and BRCA2 6174delT mutations: a combined analysis of 22 population based studies

PubMed Central

Antoniou, A; Pharoah, P; Narod, S; Risch, H; Eyfjord, J; Hopper, J; Olsson, H; Johannsson, O; Borg, A; Pasini, B; Radice, P; Manoukian, S; Eccles, D; Tang, N; Olah, E; Anton-Culver, H; Warner, E; Lubinski, J; Gronwald, J; Gorski, B; Tulinius, H; Thorlacius, S; Eerola, H; Nevanlinna, H; Syrjakoski, K; Kallioniemi, O; Thompson, D; Evans, C; Peto, J; Lalloo, F; Evans, D; Easton, D

2005-01-01

A recent report estimated the breast cancer risks in carriers of the three Ashkenazi founder mutations to be higher than previously published estimates derived from population based studies. In an attempt to confirm this, the breast and ovarian cancer risks associated with the three Ashkenazi founder mutations were estimated using families included in a previous meta-analysis of populatrion based studies. The estimated breast cancer risks for each of the founder BRCA1 and BRCA2 mutations were similar to the corresponding estimates based on all BRCA1 or BRCA2 mutations in the meta-analysis. These estimates appear to be consistent with the observed prevalence of the mutations in the Ashkenazi Jewish population. PMID:15994883

An introduction to medical statistics for health care professionals: Hypothesis tests and estimation.

PubMed

Thomas, Elaine

2005-01-01

This article is the second in a series of three that will give health care professionals (HCPs) a sound introduction to medical statistics (Thomas, 2004). The objective of research is to find out about the population at large. However, it is generally not possible to study the whole of the population and research questions are addressed in an appropriate study sample. The next crucial step is then to use the information from the sample of individuals to make statements about the wider population of like individuals. This procedure of drawing conclusions about the population, based on study data, is known as inferential statistics. The findings from the study give us the best estimate of what is true for the relevant population, given the sample is representative of the population. It is important to consider how accurate this best estimate is, based on a single sample, when compared to the unknown population figure. Any difference between the observed sample result and the population characteristic is termed the sampling error. This article will cover the two main forms of statistical inference (hypothesis tests and estimation) along with issues that need to be addressed when considering the implications of the study results. Copyright (c) 2005 Whurr Publishers Ltd.

Psychological Abuse between Parents: Associations with Child Maltreatment from a Population-Based Sample

ERIC Educational Resources Information Center

Chang, Jen Jen; Theodore, Adrea D.; Martin, Sandra L.; Runyan, Desmond K.

2008-01-01

Objective: This study examined the association between partner psychological abuse and child maltreatment perpetration. Methods: This cross-sectional study examined a population-based sample of mothers with children aged 0-17 years in North and South Carolina (n = 1,149). Mothers were asked about the occurrence of potentially neglectful or abusive…

Association of Family Structure to Later Criminality: A Population-Based Follow-Up Study of Adolescent Psychiatric Inpatients in Northern Finland

ERIC Educational Resources Information Center

Ikaheimo, Olli; Laukkanen, Matti; Hakko, Helina; Rasanen, Pirkko

2013-01-01

The influence of family structure on criminality in adolescents is well acknowledged in population based studies of delinquents, but not regarding adolescent psychiatric inpatients. The association of family structure to criminality was examined among 508 adolescents receiving psychiatric inpatient treatment between 2001 and 2006. Family structure…

Reoperation Rates After Anterior Cervical Discectomy and Fusion for Cervical Spondylotic Radiculopathy and Myelopathy: A National Population-based Study.

PubMed

Park, Moon Soo; Ju, Young-Su; Moon, Seong-Hwan; Kim, Tae-Hwan; Oh, Jae Keun; Makhni, Melvin C; Riew, K Daniel

2016-10-15

National population-based cohort study. To compare the reoperation rates between cervical spondylotic radiculopathy and myelopathy in a national population of patients. There is an inherently low incidence of reoperation after surgery for cervical degenerative disease. Therefore, it is difficult to sufficiently power studies to detect differences between reoperation rates of different cervical diagnoses. National population-based databases provide large, longitudinally followed cohorts that may help overcome this challenge. We used the Korean Health Insurance Review and Assessment Service national database to select our study population. We included patients with the diagnosis of cervical spondylotic radiculopathy or myelopathy who underwent anterior cervical discectomy and fusion from January 2009 to June 2014. We separated patients into two groups based on diagnosis codes: cervical spondylotic radiculopathy or cervical spondylotic myelopathy. Age, sex, presence of diabetes, osteoporosis, associated comorbidities, number of operated cervical disc levels, and hospital types were considered potential confounding factors. The overall reoperation rate was 2.45%. The reoperation rate was significantly higher in patients with cervical spondylotic myelopathy than in patients with cervical radiculopathy (myelopathy: P = 0.0293, hazard ratio = 1.433, 95% confidence interval 1.037-1.981). Male sex, presence of diabetes or associated comorbidities, and hospital type were noted to be risk factors for reoperation. The reoperation rate after anterior cervical discectomy and fusion was higher for cervical spondylotic myelopathy than for cervical spondylotic radiculopathy in a national population of patients. 3.

The Implications of Ecologically Based Assessment for Primary Prevention with Indigenous Youth Populations

PubMed Central

Okamoto, Scott K.; LeCroy, Craig Winston; Tann, Sheila S.; Rayle, Andrea Dixon; Kulis, Stephen; Dustman, Patricia; Berceli, David

2011-01-01

This paper describes a five-stage approach toward conducting an ecologically based assessment with Indigenous youth populations, and the implications of this approach for the development and implementation of culturally grounded prevention interventions. A description of a pilot study funded by the National Institutes of Health/National Institute on Drug Abuse (NIH/NIDA) focused on drug use and American Indian youth is presented as one model for operationalizing ecologically based assessment with Indigenous youth populations, and issues related to translating the pilot study into a prevention intervention are discussed. This paper suggests that ecologically based assessment can serve as a foundation for culturally grounded prevention interventions, promoting the social and ecological validity of those interventions. PMID:16534658

The relative effects of habitat loss and fragmentation on population genetic variation in the red-cockaded woodpecker (Picoides borealis).

PubMed

Bruggeman, Douglas J; Wiegand, Thorsten; Fernández, Néstor

2010-09-01

The relative influence of habitat loss, fragmentation and matrix heterogeneity on the viability of populations is a critical area of conservation research that remains unresolved. Using simulation modelling, we provide an analysis of the influence both patch size and patch isolation have on abundance, effective population size (N(e)) and F(ST). An individual-based, spatially explicit population model based on 15 years of field work on the red-cockaded woodpecker (Picoides borealis) was applied to different landscape configurations. The variation in landscape patterns was summarized using spatial statistics based on O-ring statistics. By regressing demographic and genetics attributes that emerged across the landscape treatments against proportion of total habitat and O-ring statistics, we show that O-ring statistics provide an explicit link between population processes, habitat area, and critical thresholds of fragmentation that affect those processes. Spatial distances among land cover classes that affect biological processes translated into critical scales at which the measures of landscape structure correlated best with genetic indices. Therefore our study infers pattern from process, which contrasts with past studies of landscape genetics. We found that population genetic structure was more strongly affected by fragmentation than population size, which suggests that examining only population size may limit recognition of fragmentation effects that erode genetic variation. If effective population size is used to set recovery goals for endangered species, then habitat fragmentation effects may be sufficiently strong to prevent evaluation of recovery based on the ratio of census:effective population size alone.

Advancing Methods for U.S. Transgender Health Research

PubMed Central

Reisner, Sari L.; Deutsch, Madeline B.; Bhasin, Shalender; Bockting, Walter; Brown, George R.; Feldman, Jamie; Garofalo, Rob; Kreukels, Baudewijntje; Radix, Asa; Safer, Joshua D.; Tangpricha, Vin; T’Sjoen, Guy; Goodman, Michael

2016-01-01

Purpose of Review To describe methodological challenges, gaps, and opportunities in U.S. transgender health research. Recent Findings Lack of large prospective observational studies and intervention trials, limited data on risks and benefits of gender affirmation (e.g., hormones and surgical interventions), and inconsistent use of definitions across studies hinder evidence-based care for transgender people. Systematic high-quality observational and intervention-testing studies may be carried out using several approaches, including general population-based, health systems-based, clinic-based, venue-based, and hybrid designs. Each of these approaches has its strength and limitations; however, harmonization of research efforts is needed. Ongoing development of evidence-based clinical recommendations will benefit from a series of observational and intervention studies aimed at identification, recruitment, and follow-up of transgender people of different ages, from different racial, ethnic, and socioeconomic backgrounds and with diverse gender identities. Summary Transgender health research faces challenges that include standardization of lexicon, agreed-upon population definitions, study design, sampling, measurement, outcome ascertainment, and sample size. Application of existing and new methods is needed to fill existing gaps, increase the scientific rigor and reach of transgender health research, and inform evidence-based prevention and care for this underserved population. PMID:26845331

Venous Thromboembolism and Cerebrovascular Events in Patients with Giant Cell Arteritis: A Population-Based Retrospective Cohort Study

PubMed Central

Crowson, Cynthia S.; Makol, Ashima; Ytterberg, Steven R.; Saitta, Antonino; Salvarani, Carlo; Matteson, Eric L.; Warrington, Kenneth J.

2016-01-01

Objective To investigate the incidence of venous thromboembolism (VTE) and cerebrovascular events in a community-based incidence cohort of patients with giant cell arteritis (GCA) compared to the general population. Methods A population-based inception cohort of patients with incident GCA between January 1, 1950 and December 31, 2009 in Olmsted County, Minnesota and a cohort of non-GCA subjects from the same population were assembled and followed until December 31, 2013. Confirmed VTE and cerebrovascular events were identified through direct medical record review. Results The study population included 244 patients with GCA with a mean ± SD age at diagnosis of 76.2 ± 8.2 years (79% women) and an average length of follow-up of 10.2 ± 6.8 years. Compared to non-GCA subjects of similar age and sex, patients diagnosed with GCA had a higher incidence (%) of amaurosis fugax (cumulative incidence ± SE: 2.1 ± 0.9 versus 0, respectively; p = 0.014) but similar rates of stroke, transient ischemic attack (TIA), and VTE. Among patients with GCA, neither baseline characteristics nor laboratory parameters at diagnosis reliably predicted risk of VTE or cerebrovascular events. Conclusion In this population-based study, the incidence of VTE, stroke and TIA was similar in patients with GCA compared to non-GCA subjects. PMID:26901431

Multi-population Genomic Relationships for Estimating Current Genetic Variances Within and Genetic Correlations Between Populations.

PubMed

Wientjes, Yvonne C J; Bijma, Piter; Vandenplas, Jérémie; Calus, Mario P L

2017-10-01

Different methods are available to calculate multi-population genomic relationship matrices. Since those matrices differ in base population, it is anticipated that the method used to calculate genomic relationships affects the estimate of genetic variances, covariances, and correlations. The aim of this article is to define the multi-population genomic relationship matrix to estimate current genetic variances within and genetic correlations between populations. The genomic relationship matrix containing two populations consists of four blocks, one block for population 1, one block for population 2, and two blocks for relationships between the populations. It is known, based on literature, that by using current allele frequencies to calculate genomic relationships within a population, current genetic variances are estimated. In this article, we theoretically derived the properties of the genomic relationship matrix to estimate genetic correlations between populations and validated it using simulations. When the scaling factor of across-population genomic relationships is equal to the product of the square roots of the scaling factors for within-population genomic relationships, the genetic correlation is estimated unbiasedly even though estimated genetic variances do not necessarily refer to the current population. When this property is not met, the correlation based on estimated variances should be multiplied by a correction factor based on the scaling factors. In this study, we present a genomic relationship matrix which directly estimates current genetic variances as well as genetic correlations between populations. Copyright © 2017 by the Genetics Society of America.

Genetics of the Shimokita macaque population suggest an ancient bottleneck.

PubMed

Kawamoto, Yoshi; Tomari, Ken-ichiro; Kawai, Shizuka; Kawamoto, Sakie

2008-01-01

The macaque population of the Shimokita Peninsula represents the northernmost distribution of this species and is isolated from other populations in the Tohoku region of Japan. A previous protein-based study revealed a high level of genetic variability in this population and considerable differentiation from other populations. In order to reassess the genetic features of the Shimokita macaques, we examined 11 autosomal microsatellite loci and three Y chromosomal microsatellite loci. We observed considerable differentiation from other Japanese populations of macaques, but in contrast to the previous results, we observed significantly lower genetic variability in this population. There was a weak indication of a population bottleneck, suggesting a decay over time from an excess of heterozygotes that might be expected in the initial stages of a bottleneck. This may indicate that an ancient bottleneck occurred during the warm period after the last glacial period rather than a recent bottleneck due to hunting in modern times. The frequencies of private alleles were exceptionally high in the Shimokita population, suggesting that the difference in variability as determined in various studies was due to accidental sampling of marker loci with low power to resolve genetic variations in the protein-based studies. The assessments of interpopulation differentiation as determined using autosomal and Y chromosomal markers were highly correlated, and using both types of markers the Shimokita population was found to be the most differentiated of the study populations, probably due to infrequent gene flow with surrounding populations.

The Prevalence of Amblyopia and Its Determinants in a Population-based Study.

PubMed

Faghihi, Mohammad; Hashemi, Hassan; Nabovati, Payam; Saatchi, Mohammad; Yekta, Abbasali; Rafati, Shokoofeh; Ostadimoghaddam, Hadi; Khabazkhoob, Mehdi

2017-12-01

To determine the prevalence of amblyopia and its determinants in a population-based study in Mashhad County, Iran. This cross-sectional, population-based study was conducted on the population of Mashhad County aged >1 year using randomized stratified cluster sampling. Examinations were performed after selection of the participants and their free transportation to the sampling site. The examinations included the measurement of uncorrected and corrected visual acuity, cycloplegic and non-cycloplegic refraction, cover testing, slit-lamp biomicroscopy, and ophthalmoscopy. In this study, amblyopia was defined as best corrected visual acuity (BCVA) of 20/30 or less or 2-line interocular optotype acuity differences with no pathology. After considering the exclusion criteria, the data of 2739 individuals, 65.6% of whom were women, were analyzed. The mean age of the participants was 29.5±17.5 years. The prevalence of amblyopia was 4.6% (95% CI: 3.77%-5.43%) in the total population. The lowest prevalence was 2.24% in the age group 5-15 years (95% CI: 0.99%-3.48%) and the highest prevalence was 7.14% in the age group 55-65 years (95% CI: 2.64%-11.56%). Anisometropic amblyopia was observed in 45.24% of the amblyopic participants. Isometropic, mixed (strabismic/anisometropic), and strabismic amblyopia were other common causes of amblyopia, with a prevalence of 24.6%, 16.67%, and 13.49% in amblyopic patients, respectively. The odds ratio (OR) of having amblyopia for each 1-year increase in age was 1.02 (95% CI: 1.01-1.03). Amblyopia was less common in people with better socioeconomic status. This study showed the prevalence of amblyopia in all age groups in a population-based study for the first time. The findings of this study regarding the relatively high prevalence of amblyopia in the older population and its lower prevalence in young people indicate attention to amblyopia in recent years.

Genetic variation and structure in remnant population of critically endangered Melicope zahlbruckneri

USGS Publications Warehouse

Raji, J. A.; Atkinson, Carter T.

2016-01-01

The distribution and amount of genetic variation within and between populations of plant species are important for their adaptability to future habitat changes and also critical for their restoration and overall management. This study was initiated to assess the genetic status of the remnant population of Melicope zahlbruckneri–a critically endangered species in Hawaii, and determine the extent of genetic variation and diversity in order to propose valuable conservation approaches. Estimated genetic structure of individuals based on molecular marker allele frequencies identified genetic groups with low overall differentiation but identified the most genetically diverse individuals within the population. Analysis of Amplified Fragment Length Polymorphic (AFLP) marker loci in the population based on Bayesian model and multivariate statistics classified the population into four subgroups. We inferred a mixed species population structure based on Bayesian clustering and frequency of unique alleles. The percentage of Polymorphic Fragment (PPF) ranged from 18.8 to 64.6% for all marker loci with an average of 54.9% within the population. Inclusion of all surviving M. zahlbruckneri trees in future restorative planting at new sites are suggested, and approaches for longer term maintenance of genetic variability are discussed. To our knowledge, this study represents the first report of molecular genetic analysis of the remaining population of M. zahlbruckneri and also illustrates the importance of genetic variability for conservation of a small endangered population.

Risk of erectile dysfunction in transfusion-naive thalassemia men: a nationwide population-based retrospective cohort study.

PubMed

Chen, Yu-Guang; Lin, Te-Yu; Lin, Cheng-Li; Dai, Ming-Shen; Ho, Ching-Liang; Kao, Chia-Hung

2015-04-01

Based on the mechanism of pathophysiology, thalassemia major or transfusion-dependent thalassemia patients may have an increased risk of developing organic erectile dysfunction resulting from hypogonadism. However, there have been few studies investigating the association between erectile dysfunction and transfusion-naive thalassemia populations. We constructed a population-based cohort study to elucidate the association between transfusion-naive thalassemia populations and organic erectile dysfunction. This nationwide population-based cohort study involved analyzing data from 1998 to 2010 obtained from the Taiwanese National Health Insurance Research Database, with a follow-up period extending to the end of 2011. We identified men with transfusion-naive thalassemia and selected a comparison cohort that was frequency-matched with these according to age, and year of diagnosis thalassemia at a ratio of 1 thalassemia man to 4 control men. We analyzed the risks for transfusion-naive thalassemia men and organic erectile dysfunction by using Cox proportional hazards regression models. In this study, 588 transfusion-naive thalassemia men and 2337 controls were included. Total 12 patients were identified within the thalassaemia group and 10 within the control group. The overall risks for developing organic erectile dysfunction were 4.56-fold in patients with transfusion-naive thalassemia men compared with the comparison cohort after we adjusted for age and comorbidities. Our long-term cohort study results showed that in transfusion-naive thalassemia men, there was a higher risk for the development of organic erectile dysfunction, particularly in those patients with comorbidities.

Assessing population exposure for landslide risk analysis using dasymetric cartography

NASA Astrophysics Data System (ADS)

Garcia, Ricardo A. C.; Oliveira, Sergio C.; Zezere, Jose L.

2015-04-01

Exposed Population is a major topic that needs to be taken into account in a full landslide risk analysis. Usually, risk analysis is based on an accounting of inhabitants number or inhabitants density, applied over statistical or administrative terrain units, such as NUTS or parishes. However, this kind of approach may skew the obtained results underestimating the importance of population, mainly in territorial units with predominance of rural occupation. Furthermore, the landslide susceptibility scores calculated for each terrain unit are frequently more detailed and accurate than the location of the exposed population inside each territorial unit based on Census data. These drawbacks are not the ideal setting when landslide risk analysis is performed for urban management and emergency planning. Dasymetric cartography, which uses a parameter or set of parameters to restrict the spatial distribution of a particular phenomenon, is a methodology that may help to enhance the resolution of Census data and therefore to give a more realistic representation of the population distribution. Therefore, this work aims to map and to compare the population distribution based on a traditional approach (population per administrative terrain units) and based on dasymetric cartography (population by building). The study is developed in the Region North of Lisbon using 2011 population data and following three main steps: i) the landslide susceptibility assessment based on statistical models independently validated; ii) the evaluation of population distribution (absolute and density) for different administrative territorial units (Parishes and BGRI - the basic statistical unit in the Portuguese Census); and iii) the dasymetric population's cartography based on building areal weighting. Preliminary results show that in sparsely populated administrative units, population density differs more than two times depending on the application of the traditional approach or the dasymetric cartography. This work was supported by the FCT - Portuguese Foundation for Science and Technology.

The Italian Hub of Population Biobanks as a Potential Tool for Improving Public Health Stewardship

PubMed Central

Napolitano, Mariarosaria; Santoro, Filippo; Belardelli, Filippo; Federici, Antonio

2013-01-01

In Italy, a country that is experiencing the decentralization of health services from central to regional level of government, the Minister of Health is proposing stewardship as a model of governance for the public health system. Stewardship favors efficiency in the policy decision-making process, based on reciprocal trust, and tends to be more ethical. The embryonic proposal to test stewardship in the field of population-based research was advanced during the launching conference Challenges and Opportunities of the Italian Hub of Population Biobanks (HIBP) held in 2012 in Rome. Resources collected by population biobanks (i.e., blood and its derivatives, and/or DNA isolated from any type of biological samples and relative associated data) have, in fact, a recognized scientific value for the investigation of links between genetics, health and life style, and epidemiological outcomes through population biobank-based studies, and are essential to planning effective and qualified interventions for public health. The current economic crisis requires a strong push to rationalize investment in health policies. In particular, population biobank-based studies require financial commitment, often of long duration, for the realization of their goals. Thus, innovative solutions to allow fast integration of scientific knowledge into political health strategy are required. During the conference in Rome, it was proposed to test the stewardship model by its application to the inter-relationship between population biobank-based studies and disease prevention. Stewardship minimizes barriers to innovation and uses information more effectively to better develop new strategies for prevention and/or treatment. In the months following the conference, the proposal was defined more clearly, and the HIBP network became a potential tool for testing and implementing this model in the Italian Public Health prevention system. PMID:23840926

Improved imputation accuracy of rare and low-frequency variants using population-specific high-coverage WGS-based imputation reference panel.

PubMed

Mitt, Mario; Kals, Mart; Pärn, Kalle; Gabriel, Stacey B; Lander, Eric S; Palotie, Aarno; Ripatti, Samuli; Morris, Andrew P; Metspalu, Andres; Esko, Tõnu; Mägi, Reedik; Palta, Priit

2017-06-01

Genetic imputation is a cost-efficient way to improve the power and resolution of genome-wide association (GWA) studies. Current publicly accessible imputation reference panels accurately predict genotypes for common variants with minor allele frequency (MAF)≥5% and low-frequency variants (0.5≤MAF<5%) across diverse populations, but the imputation of rare variation (MAF<0.5%) is still rather limited. In the current study, we evaluate imputation accuracy achieved with reference panels from diverse populations with a population-specific high-coverage (30 ×) whole-genome sequencing (WGS) based reference panel, comprising of 2244 Estonian individuals (0.25% of adult Estonians). Although the Estonian-specific panel contains fewer haplotypes and variants, the imputation confidence and accuracy of imputed low-frequency and rare variants was significantly higher. The results indicate the utility of population-specific reference panels for human genetic studies.

Improved imputation accuracy of rare and low-frequency variants using population-specific high-coverage WGS-based imputation reference panel

PubMed Central

Mitt, Mario; Kals, Mart; Pärn, Kalle; Gabriel, Stacey B; Lander, Eric S; Palotie, Aarno; Ripatti, Samuli; Morris, Andrew P; Metspalu, Andres; Esko, Tõnu; Mägi, Reedik; Palta, Priit

2017-01-01

Genetic imputation is a cost-efficient way to improve the power and resolution of genome-wide association (GWA) studies. Current publicly accessible imputation reference panels accurately predict genotypes for common variants with minor allele frequency (MAF)≥5% and low-frequency variants (0.5≤MAF<5%) across diverse populations, but the imputation of rare variation (MAF<0.5%) is still rather limited. In the current study, we evaluate imputation accuracy achieved with reference panels from diverse populations with a population-specific high-coverage (30 ×) whole-genome sequencing (WGS) based reference panel, comprising of 2244 Estonian individuals (0.25% of adult Estonians). Although the Estonian-specific panel contains fewer haplotypes and variants, the imputation confidence and accuracy of imputed low-frequency and rare variants was significantly higher. The results indicate the utility of population-specific reference panels for human genetic studies. PMID:28401899

Prevalence of autosomal dominant polycystic kidney disease in the European Union.

PubMed

Willey, Cynthia J; Blais, Jaime D; Hall, Anthony K; Krasa, Holly B; Makin, Andrew J; Czerwiec, Frank S

2017-08-01

Autosomal dominant polycystic kidney disease (ADPKD) is a leading cause of end-stage renal disease, but estimates of its prevalence vary by >10-fold. The objective of this study was to examine the public health impact of ADPKD in the European Union (EU) by estimating minimum prevalence (point prevalence of known cases) and screening prevalence (minimum prevalence plus cases expected after population-based screening). A review of the epidemiology literature from January 1980 to February 2015 identified population-based studies that met criteria for methodological quality. These examined large German and British populations, providing direct estimates of minimum prevalence and screening prevalence. In a second approach, patients from the 2012 European Renal Association‒European Dialysis and Transplant Association (ERA-EDTA) Registry and literature-based inflation factors that adjust for disease severity and screening yield were used to estimate prevalence across 19 EU countries (N = 407 million). Population-based studies yielded minimum prevalences of 2.41 and 3.89/10 000, respectively, and corresponding estimates of screening prevalences of 3.3 and 4.6/10 000. A close correspondence existed between estimates in countries where both direct and registry-derived methods were compared, which supports the validity of the registry-based approach. Using the registry-derived method, the minimum prevalence was 3.29/10 000 (95% confidence interval 3.27-3.30), and if ADPKD screening was implemented in all countries, the expected prevalence was 3.96/10 000 (3.94-3.98). ERA-EDTA-based prevalence estimates and application of a uniform definition of prevalence to population-based studies consistently indicate that the ADPKD point prevalence is <5/10 000, the threshold for rare disease in the EU. © The Author 2016. Published by Oxford University Press on behalf of ERA-EDTA.

Changes in Patterns of Age-Related Visual Impairment in the Netherlands: A Comparison of Two Cohorts of Patients Referred to Rehabilitation Programs 10 Years Apart

ERIC Educational Resources Information Center

van Rens, Ger H. M. B.; Lens, Judith A.; de Boer, Michael R.

2006-01-01

Most of the studies of the causes of visual impairment have been population-based studies. These population-based studies provide important information on the incidence and prevalence of "theoretical" eye problems in a community. However, not all those who are visually impaired, from a theoretical point of view, consider themselves as…

Does Universally Accessible Child Care Protect Children from Late Talking? Results from a Norwegian Population-Based Prospective Study

ERIC Educational Resources Information Center

Lekhal, Ratib; Zachrisson, Henrik Daae; Wang, Mari Vaage; Schjolberg, Synnve; von Soest, Tilmann

2011-01-01

This study examines the association between type of child care arrangement at age 1, 1.5 and 3 years and late talking (LT). The data were from 19,919 children in the population-based prospective Norwegian Mother and Child Cohort Study (MoBa) and included information about child care arrangement, LT and a variety of covariates. Attendance at…

The prevalence of ADHD in a population-based sample

PubMed Central

Rowland, Andrew S.; Skipper, Betty J.; Umbach, David M.; Rabiner, David L.; Campbell, Richard A.; Naftel, A. Jack; Sandler, Dale P.

2014-01-01

Objective Few studies of ADHD prevalence have used population-based samples, multiple informants, and DSM-IV criteria. In addition, children who are asymptomatic while receiving ADHD mediction often have been misclassified. Therefore, we conducted a population-based study to estimate the prevalence of ADHD in elementary school children using DSM-IV critera. Methods We screened 7587 children for ADHD. Teachers of 81% of the children completed a DSM-IV checklist. We then interviewed parents using a structured interview (DISC). Of these, 72% participated. Parent and teacher ratings were combined to determine ADHD status. We also estimated the proportion of cases attributable to other conditions. Results Overall, 15.5% of our sample (95% confidence interval (C.I.) 14.6%-16.4%) met DSM-IV-TR criteria for ADHD. Over 40% of cases reported no previous diagnosis. With additional information, other conditions explained about 9% of cases. Conclusions The prevalence of ADHD in this population-based sample was higher than the 3-7% commonly reported. To compare study results, the methods used to implement the DSM criteria need to be standardized. PMID:24336124

[New population curves in spanish extremely preterm neonates].

PubMed

García-Muñoz Rodrigo, F; García-Alix Pérez, A; Figueras Aloy, J; Saavedra Santana, P

2014-08-01

Most anthropometric reference data for extremely preterm infants used in Spain are outdated and based on non-Spanish populations, or are derived from small hospital-based samples that failed to include neonates of borderline viability. To develop gender-specific, population-based curves for birth weight, length, and head circumference in extremely preterm Caucasian infants, using a large contemporary sample size of Spanish singletons. Anthropometric data from neonates ≤ 28 weeks of gestational age were collected between January 2002 and December 2010 using the Spanish database SEN1500. Gestational age was estimated according to obstetric data (early pregnancy ultrasound). The data were analyzed with the SPSS.20 package, and centile tables were created for males and females using the Cole and Green LMS method. This study presents the first population-based growth curves for extremely preterm infants, including those of borderline viability, in Spain. A sexual dimorphism is evident for all of the studied parameters, starting at early gestation. These new gender-specific and population-based data could be useful for the improvement of growth assessments of extremely preterm infants in our country, for the development of epidemiological studies, for the evaluation of temporal trends, and for clinical or public health interventions seeking to optimize fetal growth. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

Genome-wide analysis of signatures of selection in populations of African honey bees (Apis mellifera) using new web-based tools.

PubMed

Fuller, Zachary L; Niño, Elina L; Patch, Harland M; Bedoya-Reina, Oscar C; Baumgarten, Tracey; Muli, Elliud; Mumoki, Fiona; Ratan, Aakrosh; McGraw, John; Frazier, Maryann; Masiga, Daniel; Schuster, Stephen; Grozinger, Christina M; Miller, Webb

2015-07-10

With the development of inexpensive, high-throughput sequencing technologies, it has become feasible to examine questions related to population genetics and molecular evolution of non-model species in their ecological contexts on a genome-wide scale. Here, we employed a newly developed suite of integrated, web-based programs to examine population dynamics and signatures of selection across the genome using several well-established tests, including F ST, pN/pS, and McDonald-Kreitman. We applied these techniques to study populations of honey bees (Apis mellifera) in East Africa. In Kenya, there are several described A. mellifera subspecies, which are thought to be localized to distinct ecological regions. We performed whole genome sequencing of 11 worker honey bees from apiaries distributed throughout Kenya and identified 3.6 million putative single-nucleotide polymorphisms. The dense coverage allowed us to apply several computational procedures to study population structure and the evolutionary relationships among the populations, and to detect signs of adaptive evolution across the genome. While there is considerable gene flow among the sampled populations, there are clear distinctions between populations from the northern desert region and those from the temperate, savannah region. We identified several genes showing population genetic patterns consistent with positive selection within African bee populations, and between these populations and European A. mellifera or Asian Apis florea. These results lay the groundwork for future studies of adaptive ecological evolution in honey bees, and demonstrate the use of new, freely available web-based tools and workflows ( http://usegalaxy.org/r/kenyanbee ) that can be applied to any model system with genomic information.

Comprehensive Challenges for the Well Being of Young Children: A Population-Based Study of Publicly Monitored Risks in a Large Urban Center

ERIC Educational Resources Information Center

Rouse, Heather L.; Fantuzzo, John W.; LeBoeuf, Whitney

2011-01-01

This population-based study investigated the unique and cumulative relations between risks that are monitored by public surveillance systems and academic and behavioral outcomes for an entire cohort of third graders in a large, urban public school system. Using integrated, administrative records from child welfare, public health, housing, and…

Methods of Suicide among Cancer Patients: A Nationwide Population-Based Study

ERIC Educational Resources Information Center

Chung, Kuo-Hsuan; Lin, Herng-Ching

2010-01-01

A 3-year nationwide population-based data set was used to explore methods of suicide (violent vs. nonviolent) and possible contributing factors among cancer patients in Taiwan. A total of 1,065 cancer inpatients who committed suicide were included as our study sample. The regression shows that those who had genitourinary cancer were 0.55 times (p…

Relation of Infant Motor Development with Nonverbal Intelligence, Language Comprehension and Neuropsychological Functioning in Childhood: A Population-Based Study

ERIC Educational Resources Information Center

Serdarevic, Fadila; van Batenburg-Eddes, Tamara; Mous, Sabine E.; White, Tonya; Hofman, Albert; Jaddoe, Vincent W. V.; Verhulst, Frank C.; Ghassabian, Akhgar; Tiemeier, Henning

2016-01-01

Within a population-based study of 3356 children, we investigated whether infant neuromotor development was associated with cognition in early childhood. Neuromotor development was examined with an adapted version of Touwen's Neurodevelopmental Examination between 9 and 20 weeks. Parents rated their children's executive functioning at 4 years. At…

Additive influence of genetic predisposition and conventional risk factors in the incidence of coronary heart disease: a population-based study in Greece

USDA-ARS?s Scientific Manuscript database

An additive genetic risk score (GRS) for coronary heart disease (CHD) has previously been associated with incident CHD in the population-based Greek European Prospective Investigation into Cancer and nutrition (EPIC) cohort. In this study, we explore GRS-‘environment’ joint actions on CHD for severa...

Long-Term Benefits of Full-Day Kindergarten: A Longitudinal Population-Based Study

ERIC Educational Resources Information Center

Brownell, M. D.; Nickel, N. C.; Chateau, D.; Martens, P. J.; Taylor, C.; Crockett, L.; Katz, A.; Sarkar, J.; Burland, E.; Goh, C. Y.

2015-01-01

In the first longitudinal, population-based study of full-day kindergarten (FDK) outcomes beyond primary school in Canada, we used linked administrative data to follow 15 kindergarten cohorts (n ranging from 112 to 736) up to grade 9. Provincial assessments conducted in grades 3, 7, and 8 and course marks and credits earned in grade 9 were…

Conduct of a personal radiofrequency electromagnetic field measurement study: proposed study protocol.

PubMed

Röösli, Martin; Frei, Patrizia; Bolte, John; Neubauer, Georg; Cardis, Elisabeth; Feychting, Maria; Gajsek, Peter; Heinrich, Sabine; Joseph, Wout; Mann, Simon; Martens, Luc; Mohler, Evelyn; Parslow, Roger C; Poulsen, Aslak Harbo; Radon, Katja; Schüz, Joachim; Thuroczy, György; Viel, Jean-François; Vrijheid, Martine

2010-05-20

The development of new wireless communication technologies that emit radio frequency electromagnetic fields (RF-EMF) is ongoing, but little is known about the RF-EMF exposure distribution in the general population. Previous attempts to measure personal exposure to RF-EMF have used different measurement protocols and analysis methods making comparisons between exposure situations across different study populations very difficult. As a result, observed differences in exposure levels between study populations may not reflect real exposure differences but may be in part, or wholly due to methodological differences. The aim of this paper is to develop a study protocol for future personal RF-EMF exposure studies based on experience drawn from previous research. Using the current knowledge base, we propose procedures for the measurement of personal exposure to RF-EMF, data collection, data management and analysis, and methods for the selection and instruction of study participants. We have identified two basic types of personal RF-EMF measurement studies: population surveys and microenvironmental measurements. In the case of a population survey, the unit of observation is the individual and a randomly selected representative sample of the population is needed to obtain reliable results. For microenvironmental measurements, study participants are selected in order to represent typical behaviours in different microenvironments. These two study types require different methods and procedures. Applying our proposed common core procedures in future personal measurement studies will allow direct comparisons of personal RF-EMF exposures in different populations and study areas.

Conduct of a personal radiofrequency electromagnetic field measurement study: proposed study protocol

PubMed Central

2010-01-01

Background The development of new wireless communication technologies that emit radio frequency electromagnetic fields (RF-EMF) is ongoing, but little is known about the RF-EMF exposure distribution in the general population. Previous attempts to measure personal exposure to RF-EMF have used different measurement protocols and analysis methods making comparisons between exposure situations across different study populations very difficult. As a result, observed differences in exposure levels between study populations may not reflect real exposure differences but may be in part, or wholly due to methodological differences. Methods The aim of this paper is to develop a study protocol for future personal RF-EMF exposure studies based on experience drawn from previous research. Using the current knowledge base, we propose procedures for the measurement of personal exposure to RF-EMF, data collection, data management and analysis, and methods for the selection and instruction of study participants. Results We have identified two basic types of personal RF-EMF measurement studies: population surveys and microenvironmental measurements. In the case of a population survey, the unit of observation is the individual and a randomly selected representative sample of the population is needed to obtain reliable results. For microenvironmental measurements, study participants are selected in order to represent typical behaviours in different microenvironments. These two study types require different methods and procedures. Conclusion Applying our proposed common core procedures in future personal measurement studies will allow direct comparisons of personal RF-EMF exposures in different populations and study areas. PMID:20487532

Genetic diversity based on 28S rDNA sequences among populations of Culex quinquefasciatus collected at different locations in Tamil Nadu, India.

PubMed

Sakthivelkumar, S; Ramaraj, P; Veeramani, V; Janarthanan, S

2015-09-01

The basis of the present study was to distinguish the existence of any genetic variability among populations of Culex quinquefasciatus which would be a valuable tool in the management of mosquito control programmes. In the present study, population of Cx. quinquefasciatus collected at different locations in Tamil Nadu were analyzed for their genetic variation based on 28S rDNA D2 region nucleotide sequences. A high degree of genetic polymorphism was detected in the sequences of D2 region of 28S rDNA on the predicted secondary structures in spite of high nucleotide sequence similarity. The findings based on secondary structure using rDNA sequences suggested the existence of a complex genotypic diversity of Cx. quinquefasciatus population collected at different locations of Tamil Nadu, India. This complexity in genetic diversity in a single mosquito population collected at different locations is considered an important issue towards their influence and nature of vector potential of these mosquitoes.

The HealthNuts population-based study of paediatric food allergy: validity, safety and acceptability.

PubMed

Osborne, N J; Koplin, J J; Martin, P E; Gurrin, L C; Thiele, L; Tang, M L; Ponsonby, A-L; Dharmage, S C; Allen, K J

2010-10-01

The incidence of hospital admissions for food allergy-related anaphylaxis in Australia has increased, in line with world-wide trends. However, a valid measure of food allergy prevalence and risk factor data from a population-based study is still lacking. To describe the study design and methods used to recruit infants from a population for skin prick testing and oral food challenges, and the use of preliminary data to investigate the extent to which the study sample is representative of the target population. The study sampling frame design comprises 12-month-old infants presenting for routine scheduled vaccination at immunization clinics in Melbourne, Australia. We compared demographic features of participating families to population summary statistics from the Victorian Perinatal census database, and administered a survey to those non-responders who chose not to participate in the study. Study design proved acceptable to the community with good uptake (response rate 73.4%), with 2171 participants recruited. Demographic information on the study population mirrored the Victorian population with most the population parameters measured falling within our confidence intervals (CI). Use of a non-responder questionnaire revealed that a higher proportion of infants who declined to participate (non-responders) were already eating and tolerating peanuts, than those agreeing to participate (54.4%; 95% CI 50.8, 58.0 vs. 27.4%; 95% CI 25.5, 29.3 among participants). A high proportion of individuals approached in a community setting participated in a food allergy study. The study population differed from the eligible sample in relation to family history of allergy and prior consumption and peanut tolerance, providing some insights into the internal validity of the sample. The study exhibited external validity on general demographics to all births in Victoria. © 2010 Blackwell Publishing Ltd.

Genetic variation and forensic characteristic analysis of 25 STRs of a novel fluorescence co-amplification system in Chinese Southern Shaanxi Han population.

PubMed

Liu, Yao-Shun; Chen, Jian-Gang; Mei, Ting; Guo, Yu-Xin; Meng, Hao-Tian; Li, Jian-Fei; Wei, Yuan-Yuan; Jin, Xiao-Ye; Zhu, Bo-Feng; Zhang, Li-Ping

2017-08-15

We analyzed the genetic polymorphisms of 15 autosomal and 10 Y-chromosomal STR loci in 214 individuals of Han population from Southern Shaanxi of China and studied the genetic relationships between Southern Shaanxi Han and other populations. We observed a total of 150 alleles at 15 autosomal STR loci with the corresponding allelic frequencies ranging from 0.0023 to 0.5210, and the combined power of discrimination and exclusion for the 15 autosomal STR loci were 0.99999999999999998866 and 0.999998491, respectively. For the 10 Y-STR loci, totally 100 different haplotypes were obtained, of which 94 were unique. The discriminatory capacity and haplotype diversity values of the 10 Y-STR loci were 0.9259 and 0.998269, respectively. The results demonstrated high genetic diversities of the 25 STR loci in the population for forensic applications. We constructed neighbor-joining tree and conducted principal component analysis based on 15 autosomal STR loci and conducted multidimensional scaling analysis and constructed neighbor-joining tree based on 10 Y-STR loci. The results of population genetic analyses based on both autosomal and Y-chromosome STRs indicated that the studied Southern Shaanxi Han population had relatively closer genetic relationship with Eastern Han population, and distant relationships with Croatian, Serbian and Moroccan populations.

Prevalence of sexually transmitted infections and bacterial vaginosis among women in sub-Saharan Africa: An individual participant data meta-analysis of 18 HIV prevention studies

PubMed Central

Morrison, Charles S.; Chen, Pai-Lien; Kwok, Cynthia; McCormack, Sheena; McGrath, Nuala; Watson-Jones, Deborah; Gottlieb, Sami L.

2018-01-01

Background Estimates of sexually transmitted infection (STI) prevalence are essential for efforts to prevent and control STIs. Few large STI prevalence studies exist, especially for low- and middle-income countries (LMICs). Our primary objective was to estimate the prevalence of chlamydia, gonorrhea, trichomoniasis, syphilis, herpes simplex virus type 2 (HSV-2), and bacterial vaginosis (BV) among women in sub-Saharan Africa by age, region, and population type. Methods and findings We analyzed individual-level data from 18 HIV prevention studies (cohort studies and randomized controlled trials; conducted during 1993–2011), representing >37,000 women, that tested participants for ≥1 selected STIs or BV at baseline. We used a 2-stage meta-analysis to combine data. After calculating the proportion of participants with each infection and standard error by study, we used a random-effects model to obtain a summary mean prevalence of each infection and 95% confidence interval (CI) across ages, regions, and population types. Despite substantial study heterogeneity for some STIs/populations, several patterns emerged. Across the three primary region/population groups (South Africa community-based, Southern/Eastern Africa community-based, and Eastern Africa higher-risk), prevalence was higher among 15–24-year-old than 25–49-year-old women for all STIs except HSV-2. In general, higher-risk populations had greater prevalence of gonorrhea and syphilis than clinic/community-based populations. For chlamydia, prevalence among 15–24-year-olds was 10.3% (95% CI: 7.4%, 14.1%; I2 = 75.7%) among women specifically recruited from higher-risk settings for HIV in Eastern Africa and was 15.1% (95% CI: 12.7%, 17.8%; I2 = 82.3%) in South African clinic/community-based populations. Among clinic/community-based populations, prevalence was generally greater in South Africa than in Southern/Eastern Africa for most STIs; for gonorrhea, prevalence among 15–24-year-olds was 4.6% (95% CI: 3.3%, 6.4%; I2 = 82.8%) in South Africa and was 1.7% (95% CI: 1.2%, 2.6%; I2 = 55.2%) in Southern/Eastern Africa. Across the three primary region/population groups, HSV-2 and BV prevalence was high among 25–49-year-olds (ranging from 70% to 83% and 33% to 44%, respectively). The main study limitation is that the data are not from random samples of the target populations. Conclusions Combining data from 18 HIV prevention studies, our findings highlight important features of STI/BV epidemiology among sub-Saharan African women. This methodology can be used where routine STI surveillance is limited and offers a new approach to obtaining critical information on STI and BV prevalence in LMICs. PMID:29485986

Research progress of plant population genomics based on high-throughput sequencing.

PubMed

Wang, Yun-sheng

2016-08-01

Population genomics, a new paradigm for population genetics, combine the concepts and techniques of genomics with the theoretical system of population genetics and improve our understanding of microevolution through identification of site-specific effect and genome-wide effects using genome-wide polymorphic sites genotypeing. With the appearance and improvement of the next generation high-throughput sequencing technology, the numbers of plant species with complete genome sequences increased rapidly and large scale resequencing has also been carried out in recent years. Parallel sequencing has also been done in some plant species without complete genome sequences. These studies have greatly promoted the development of population genomics and deepened our understanding of the genetic diversity, level of linking disequilibium, selection effect, demographical history and molecular mechanism of complex traits of relevant plant population at a genomic level. In this review, I briely introduced the concept and research methods of population genomics and summarized the research progress of plant population genomics based on high-throughput sequencing. I also discussed the prospect as well as existing problems of plant population genomics in order to provide references for related studies.

A Markov chain model for studying suicide dynamics: an illustration of the Rose theorem

PubMed Central

2014-01-01

Background High-risk strategies would only have a modest effect on suicide prevention within a population. It is best to incorporate both high-risk and population-based strategies to prevent suicide. This study aims to compare the effectiveness of suicide prevention between high-risk and population-based strategies. Methods A Markov chain illness and death model is proposed to determine suicide dynamic in a population and examine its effectiveness for reducing the number of suicides by modifying certain parameters of the model. Assuming a population with replacement, the suicide risk of the population was estimated by determining the final state of the Markov model. Results The model shows that targeting the whole population for suicide prevention is more effective than reducing risk in the high-risk tail of the distribution of psychological distress (i.e. the mentally ill). Conclusions The results of this model reinforce the essence of the Rose theorem that lowering the suicidal risk in the population at large may be more effective than reducing the high risk in a small population. PMID:24948330

Measurement properties of performance-based outcome measures to assess physical function in young and middle-aged people known to be at high risk of hip and/or knee osteoarthritis: a systematic review.

PubMed

Kroman, S L; Roos, E M; Bennell, K L; Hinman, R S; Dobson, F

2014-01-01

To systematically appraise the evidence on measurement properties of performance-based outcome measures to assess physical function in young and middle-aged people known to be at high risk of hip and/or knee osteoarthritis (OA). Electronic searches were performed in MEDLINE, CINAHL, Scopus and SPORTDiscus in May 2013. Two reviewers independently rated the measurement properties using the 4-point COSMIN checklist. Best evidence synthesis was made using COSMIN quality, consistency and direction of findings and sample size. Twenty of 2736 papers were eligible for inclusion and 24 different performance-based outcome measures knee or obese populations were evaluated. No tests related to hip populations were included. Twenty-five measurement properties including reliability (nine studies), construct validity (hypothesis testing) (nine studies), measurement error (three studies), structural validity (two studies), interpretability (one study) and responsiveness (one study) were evaluated. A positive rating was given to 12.5% (30/240) of all possible measurement ratings. Tests were grouped into two categories based on the population characteristics. The one-legged hop for distance, followed by the 6-m timed hop and cross over hop for distance were the best-rated tests for the knee-injured population. Whereas the 6-min walk test was the only included test for the obese population. This review highlights the many gaps in knowledge about the measurement properties of performance-based outcome measures for young and middle-aged people known to be at high risk of hip and/or knee OA. There is a need for consensus on which outcome measures should be used and/or combined when assessing physical function in this population. Further good quality research is required. Copyright © 2013 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Prognostic scoring systems for myelodysplastic syndromes (MDS) in a population-based setting: a report from the Swedish MDS register.

PubMed

Moreno Berggren, Daniel; Folkvaljon, Yasin; Engvall, Marie; Sundberg, Johan; Lambe, Mats; Antunovic, Petar; Garelius, Hege; Lorenz, Fryderyk; Nilsson, Lars; Rasmussen, Bengt; Lehmann, Sören; Hellström-Lindberg, Eva; Jädersten, Martin; Ejerblad, Elisabeth

2018-06-01

The myelodysplastic syndromes (MDS) have highly variable outcomes and prognostic scoring systems are important tools for risk assessment and to guide therapeutic decisions. However, few population-based studies have compared the value of the different scoring systems. With data from the nationwide Swedish population-based MDS register we validated the International Prognostic Scoring System (IPSS), revised IPSS (IPSS-R) and the World Health Organization (WHO) Classification-based Prognostic Scoring System (WPSS). We also present population-based data on incidence, clinical characteristics including detailed cytogenetics and outcome from the register. The study encompassed 1329 patients reported to the register between 2009 and 2013, 14% of these had therapy-related MDS (t-MDS). Based on the MDS register, the yearly crude incidence of MDS in Sweden was 2·9 per 100 000 inhabitants. IPSS-R had a significantly better prognostic power than IPSS (P < 0·001). There was a trend for better prognostic power of IPSS-R compared to WPSS (P = 0·05) and for WPSS compared to IPSS (P = 0·07). IPSS-R was superior to both IPSS and WPSS for patients aged ≤70 years. Patients with t-MDS had a worse outcome compared to de novo MDS (d-MDS), however, the validity of the prognostic scoring systems was comparable for d-MDS and t-MDS. In conclusion, population-based studies are important to validate prognostic scores in a 'real-world' setting. In our nationwide cohort, the IPSS-R showed the best predictive power. © 2018 John Wiley & Sons Ltd.

Should we expect population thresholds for wildlife disease?

USGS Publications Warehouse

Lloyd-Smith, James O.; Cross, P.C.; Briggs, C.J.; Daugherty, M.; Getz, W.M.; Latto, J.; Sanchez, M.; Smith, A.; Swei, A.

2005-01-01

Host population thresholds for invasion or persistence of infectious disease are core concepts of disease ecology, and underlie on-going and controversial disease control policies based on culling and vaccination. Empirical evidence for these thresholds in wildlife populations has been sparse, however, though recent studies have narrowed this gap. Here we review the theoretical bases for population thresholds for disease, revealing why they are difficult to measure and sometimes are not even expected, and identifying important facets of wildlife ecology left out of current theories. We discuss strengths and weaknesses of selected empirical studies that have reported disease thresholds for wildlife, identify recurring obstacles, and discuss implications of our imperfect understanding of wildlife thresholds for disease control policy.

Suicide by people in a community justice pathway: population-based nested case–control study

PubMed Central

King, Carlene; Senior, Jane; Webb, Roger T.; Millar, Tim; Piper, Mary; Pearsall, Alison; Humber, Naomi; Appleby, Louis; Shaw, Jenny

2015-01-01

The elevated risk of suicide in prison and after release is a well-recognised and serious problem. Despite this, evidence concerning community-based offenders' suicide risk is sparse. We conducted a population-based nested case–control study of all people in a community justice pathway in England and Wales. Our data show 13% of general population suicides were in community justice pathways before death. Suicide risks were highest among individuals receiving police cautions, and those having recent, or impending prosecution for sexual offences. Findings have implications for the training and practice of clinicians identifying and assessing suicidality, and offering support to those at elevated risk. PMID:26159602

Genetic structure of seven Mexican indigenous populations based on five polymarker loci.

PubMed

Buentello-Malo, Leonora; Peñaloza-Espinosa, Rosenda I; Loeza, Francisco; Salamanca-Gomez, Fabio; Cerda-Flores, Ricardo M

2003-01-01

This descriptive study investigates the genetic structure of seven Mexican indigenous populations (Mixteca Alta, Mixteca Baja, Otomies, Purepecha, Nahuas-Guerrero, Nahuas-Xochimilco, and Tzeltales) on the basis of five PCR-based polymorphic DNA loci: LDLR, GYPA, HBGG, D7S8, and GC. Genetic distance and diversity analyses indicate that these Mexican indigenous are similar and that more than 96% of the total gene diversity (H(T)) can be attributed to individual variation within populations. Mixteca-Alta, Mixteca-Baja, and Nahuas-Xochimilco show indications of higher admixture with European-derived persons. The demonstration of a relative genetic homogeneity of Mexican Indians for the markers studied suggests that this population is suitable for studying disease-marker associations in the search for candidate genes of complex diseases. Copyright 2002 Wiley-Liss, Inc.

Shell productivity of the large benthic foraminifer Baculogypsina sphaerulata, based on the population dynamics in a tropical reef environment

NASA Astrophysics Data System (ADS)

Fujita, Kazuhiko; Otomaru, Maki; Lopati, Paeniu; Hosono, Takashi; Kayanne, Hajime

2016-03-01

Carbonate production by large benthic foraminifers is sometimes comparable to that of corals and coralline algae, and contributes to sedimentation on reef islands and beaches in the tropical Pacific. Population dynamic data, such as population density and size structure (size-frequency distribution), are vital for an accurate estimation of shell production of foraminifers. However, previous production estimates in tropical environments were based on a limited sampling period with no consideration of seasonality. In addition, no comparisons were made of various estimation methods to determine more accurate estimates. Here we present the annual gross shell production rate of Baculogypsina sphaerulata, estimated based on population dynamics studied over a 2-yr period on an ocean reef flat of Funafuti Atoll (Tuvalu, tropical South Pacific). The population density of B. sphaerulata increased from January to March, when northwest winds predominated and the study site was on the leeward side of reef islands, compared to other seasons when southeast trade winds predominated and the study site was on the windward side. This result suggested that wind-driven flows controlled the population density at the study site. The B. sphaerulata population had a relatively stationary size-frequency distribution throughout the study period, indicating no definite intensive reproductive period in the tropical population. Four methods were applied to estimate the annual gross shell production rates of B. sphaerulata. The production rates estimated by three of the four methods (using monthly biomass, life tables and growth increment rates) were in the order of hundreds of g CaCO3 m-2 yr-1 or cm-3 m-2 yr-1, and the simple method using turnover rates overestimated the values. This study suggests that seasonal surveys should be undertaken of population density and size structure as these can produce more accurate estimates of shell productivity of large benthic foraminifers.

The Evolution of Vicia ramuliflora (Fabaceae) at Tetraploid and Diploid Levels Revealed with FISH and RAPD

PubMed Central

Han, Ying; Liu, Yuan; Wang, Haoyou; Liu, Xiangjun

2017-01-01

Vicia ramuliflora L. is a widely distributed species in Eurasia with high economic value. For past 200 years, it has evolved a tetraploid cytotype and new subspecies at the diploid level. Based on taxonomy, cytogeography and other lines of evidence, previous studies have provided valuable information about the evolution of V. ramuliflora ploidy level, but due to the limited resolution of traditional methods, important questions remain. In this study, fluorescence in situ hybridization (FISH) and random amplified polymorphic DNA (RAPD) were used to analyze the evolution of V. ramuliflora at the diploid and tetraploid levels. Our aim was to reveal the genomic constitution and parents of the tetraploid V. ramuliflora and the relationships among diploid V. ramuliflora populations. Our study showed that the tetraploid cytotype of V. ramuliflora at Changbai Mountains (M) has identical 18S and 5S rDNA distribution patterns with the diploid Hengdaohezi population (B) and the diploid Dailing population (H). However, UPGMA clustering, Neighbor-Joining clustering and principal coordinates analysis based on RAPD showed that the tetraploid cytotype (M) has more close relationships with Qianshan diploid population T. Based on our results and the fact that interspecific hybridization among Vicia species is very difficult, we think that the tetraploid V. ramuliflora is an autotetraploid and its genomic origin still needs further study. In addition, our study also found that Qianshan diploid population (T) had evolved distinct new traits compared with other diploid populations, which hints that V. ramuliflora evolved further at diploid level. We suggest that diploid population T be re-classified as a new subspecies. PMID:28135314

The Evolution of Vicia ramuliflora (Fabaceae) at Tetraploid and Diploid Levels Revealed with FISH and RAPD.

PubMed

Han, Ying; Liu, Yuan; Wang, Haoyou; Liu, Xiangjun

2017-01-01

Vicia ramuliflora L. is a widely distributed species in Eurasia with high economic value. For past 200 years, it has evolved a tetraploid cytotype and new subspecies at the diploid level. Based on taxonomy, cytogeography and other lines of evidence, previous studies have provided valuable information about the evolution of V. ramuliflora ploidy level, but due to the limited resolution of traditional methods, important questions remain. In this study, fluorescence in situ hybridization (FISH) and random amplified polymorphic DNA (RAPD) were used to analyze the evolution of V. ramuliflora at the diploid and tetraploid levels. Our aim was to reveal the genomic constitution and parents of the tetraploid V. ramuliflora and the relationships among diploid V. ramuliflora populations. Our study showed that the tetraploid cytotype of V. ramuliflora at Changbai Mountains (M) has identical 18S and 5S rDNA distribution patterns with the diploid Hengdaohezi population (B) and the diploid Dailing population (H). However, UPGMA clustering, Neighbor-Joining clustering and principal coordinates analysis based on RAPD showed that the tetraploid cytotype (M) has more close relationships with Qianshan diploid population T. Based on our results and the fact that interspecific hybridization among Vicia species is very difficult, we think that the tetraploid V. ramuliflora is an autotetraploid and its genomic origin still needs further study. In addition, our study also found that Qianshan diploid population (T) had evolved distinct new traits compared with other diploid populations, which hints that V. ramuliflora evolved further at diploid level. We suggest that diploid population T be re-classified as a new subspecies.

Asthma exacerbation and proximity of residence to major roads: a population-based matched case-control study among the pediatric Medicaid population in Detroit, Michigan

PubMed Central

2011-01-01

Background The relationship between asthma and traffic-related pollutants has received considerable attention. The use of individual-level exposure measures, such as residence location or proximity to emission sources, may avoid ecological biases. Method This study focused on the pediatric Medicaid population in Detroit, MI, a high-risk population for asthma-related events. A population-based matched case-control analysis was used to investigate associations between acute asthma outcomes and proximity of residence to major roads, including freeways. Asthma cases were identified as all children who made at least one asthma claim, including inpatient and emergency department visits, during the three-year study period, 2004-06. Individually matched controls were randomly selected from the rest of the Medicaid population on the basis of non-respiratory related illness. We used conditional logistic regression with distance as both categorical and continuous variables, and examined non-linear relationships with distance using polynomial splines. The conditional logistic regression models were then extended by considering multiple asthma states (based on the frequency of acute asthma outcomes) using polychotomous conditional logistic regression. Results Asthma events were associated with proximity to primary roads with an odds ratio of 0.97 (95% CI: 0.94, 0.99) for a 1 km increase in distance using conditional logistic regression, implying that asthma events are less likely as the distance between the residence and a primary road increases. Similar relationships and effect sizes were found using polychotomous conditional logistic regression. Another plausible exposure metric, a reduced form response surface model that represents atmospheric dispersion of pollutants from roads, was not associated under that exposure model. Conclusions There is moderately strong evidence of elevated risk of asthma close to major roads based on the results obtained in this population-based matched case-control study. PMID:21513554

Population and performance analyses of four major populations with Illumina's FGx Forensic Genomics System.

PubMed

Churchill, Jennifer D; Novroski, Nicole M M; King, Jonathan L; Seah, Lay Hong; Budowle, Bruce

2017-09-01

The MiSeq FGx Forensic Genomics System (Illumina) enables amplification and massively parallel sequencing of 59 STRs, 94 identity informative SNPs, 54 ancestry informative SNPs, and 24 phenotypic informative SNPs. Allele frequency and population statistics data were generated for the 172 SNP loci included in this panel on four major population groups (Chinese, African Americans, US Caucasians, and Southwest Hispanics). Single-locus and combined random match probability values were generated for the identity informative SNPs. The average combined STR and identity informative SNP random match probabilities (assuming independence) across all four populations were 1.75E-67 and 2.30E-71 with length-based and sequence-based STR alleles, respectively. Ancestry and phenotype predictions were obtained using the ForenSeq™ Universal Analysis System (UAS; Illumina) based on the ancestry informative and phenotype informative SNP profiles generated for each sample. Additionally, performance metrics, including profile completeness, read depth, relative locus performance, and allele coverage ratios, were evaluated and detailed for the 725 samples included in this study. While some genetic markers included in this panel performed notably better than others, performance across populations was generally consistent. The performance and population data included in this study support that accurate and reliable profiles were generated and provide valuable background information for laboratories considering internal validation studies and implementation. Copyright © 2017 Elsevier B.V. All rights reserved.

Genetic structure of Xiphinema pachtaicum and X. index populations based on mitochondrial DNA variation.

PubMed

Gutiérrez-Gutiérrez, Carlos; Castillo, Pablo; Cantalapiedra-Navarrete, Carolina; Landa, Blanca B; Derycke, Sofie; Palomares-Rius, Juan E

2011-10-01

The dagger nematodes Xiphinema pachtaicum and X. index are two of the most widespread and frequently occurring Xiphinema spp. co-infesting vineyards and other crops and natural habitats worldwide. Sexual reproduction is rare in these species. The primary objective of this study was to determine the genetic structure of X. pachtaicum and X. index populations using eight and seven populations, respectively, from different "wine of denomination of origin (D.O.) zones" in Spain and Sardinia (Italy), by studying mitochondrial (cytochrome oxidase c subunit 1 or COI) and nuclear (D2-D3 expansion segments of 28S rDNA) markers. Both Xiphinema spp. showed low intraspecific divergence among COI sequences, ranging from 0.2% (1 base substitution) to 2.3% (10 substitutions) in X. pachtaicum and from 0.2% (1 base substitution) to 0.4% (2 substitutions) in X. index. Population genetic structure was strong for both species. Nevertheless, molecular differences among grapevine-growing areas were not significant, and intrapopulation diversity was very low. It is hypothesized that this genetic homogeneity in the nematode populations reflects their predominant parthenogenetic reproduction mode and low dispersal abilities. Our results also show that X. pachtaicum populations in Spain have possibly been established from two different populations of origin. Results also demonstrated that the two DNA regions studied are suitable diagnostic markers for X. index and X. pachtaicum.

The Case for Diabetes Population Health Improvement: Evidence-Based Programming for Population Outcomes in Diabetes

PubMed Central

Maruthur, Nisa; Mathioudakis, Nestoras; Spanakis, Elias; Rubin, Daniel; Zilbermint, Mihail; Hill-Briggs, Felicia

2017-01-01

Purpose of Review The goal of this review is to describe diabetes within a population health improvement framework and to review the evidence for a diabetes population health continuum of intervention approaches, including diabetes prevention and chronic and acute diabetes management, to improve clinical and economic outcomes. Recent Findings Recent studies have shown that compared to usual care, lifestyle interventions in prediabetes lower diabetes risk at the population-level and that group-based programs have low incremental medial cost effectiveness ratio for health systems. Effective outpatient interventions that improve diabetes control and process outcomes are multi-level, targeting the patient, provider, and healthcare system simultaneously and integrate community health workers as a liaison between the patient and community-based healthcare resources. A multi-faceted approach to diabetes management is also effective in the inpatient setting. Interventions shown to promote safe and effective glycemic control and use of evidence-based glucose management practices include provider reminder and clinical decision support systems, automated computer order entry, provider education, and organizational change. Summary Future studies should examine the cost-effectiveness of multi-faceted outpatient and inpatient diabetes management programs to determine the best financial models for incorporating them into diabetes population health strategies. PMID:28567711

Population based allele frequencies of disease associated polymorphisms in the Personalized Medicine Research Project.

PubMed

Cross, Deanna S; Ivacic, Lynn C; Stefanski, Elisha L; McCarty, Catherine A

2010-06-17

There is a lack of knowledge regarding the frequency of disease associated polymorphisms in populations and population attributable risk for many populations remains unknown. Factors that could affect the association of the allele with disease, either positively or negatively, such as race, ethnicity, and gender, may not be possible to determine without population based allele frequencies.Here we used a panel of 51 polymorphisms previously associated with at least one disease and determined the allele frequencies within the entire Personalized Medicine Research Project population based cohort. We compared these allele frequencies to those in dbSNP and other data sources stratified by race. Differences in allele frequencies between self reported race, region of origin, and sex were determined. There were 19544 individuals who self reported a single racial category, 19027 or (97.4%) self reported white Caucasian, and 11205 (57.3%) individuals were female. Of the 11,208 (57%) individuals with an identifiable region of origin 8337 or (74.4%) were German.41 polymorphisms were significantly different between self reported race at the 0.05 level. Stratification of our Caucasian population by self reported region of origin revealed 19 polymorphisms that were significantly different (p = 0.05) between individuals of different origins. Further stratification of the population by gender revealed few significant differences in allele frequencies between the genders. This represents one of the largest population based allele frequency studies to date. Stratification by self reported race and region of origin revealed wide differences in allele frequencies not only by race but also by region of origin within a single racial group. We report allele frequencies for our Asian/Hmong and American Indian populations; these two minority groups are not typically selected for population allele frequency detection. Population wide allele frequencies are important for the design and implementation of studies and for determining the relevance of a disease associated polymorphism for a given population.

Hepameta-- prevalence of hepatitis B/C and metabolic syndrome in population living in separated and segregated Roma settlements: a methodology for a cross-sectional population-based study using community-based approach.

PubMed

Gecková, Andrea Madarasová; Jarcuska, Peter; Mareková, Mária; Pella, Daniel; Siegfried, Leonard; Jarcuska, Pavol; Halánová, Monika

2014-03-01

Roma represent one of the largest and oldest minorities in Europe. Health of many of them, particularly those living in settlements, is heavily compromised by poor dwelling, low educational level, unemployment, and poverty rooted in generational poverty, segregation and discrimination. The cross-sectional population-based study using community based approach aimed to map the prevalence of viral hepatitis B/C and metabolic syndrome in the population living in separated and segregated Roma settlements and to compare it with the occurrence of the same health indicators in the majority population, considering selected risk and protective factors of these health indicators. The sample consisted of 452 Roma (mean age = 34.7; 35.2% men) and 403 non-Roma (mean age = 33.5; 45.9% men) respondents. Data were collected in 2011 via questionnaire, anthropometric measures and analysed blood and urine samples. A methodology used in the study as well as in the following scientific papers is described in the Methods section (i.e. study design, procedures, samples, methods including questionnaire, anthropometric measurements, physical measurements, blood and urine measurements). There are regions of declining prosperity due to high unemployment, long-term problems with poverty and depleted resources. Populations living in these areas, i.e. in Central and Eastern Europe in Roma settlements, are at risk of poverty, social exclusion and other factors affecting health. Therefore, we should look for successful long-term strategies and tools (e.g. Roma mediators, terrain work) in order to improve the future prospects of these minorities.

Population Genetic Structure of the Deep-Sea Precious Coral Corallium secundum from the Hawaiian Archipelago Based on Microsatellites.

NASA Astrophysics Data System (ADS)

Baco-Taylor, A.

2006-12-01

Deep-sea precious corals (Gerardia sp., Corallium lauuense, and Corallium secundum) on the Islands and seamounts of the Hawaiian Archipelago have supported an extremely profitable fishery, yet little is known about the life history and dispersal of the exploited species. Recent studies indicate significant genetic structure between shallow-water coral populations, including several species capable of long distance dispersal. If significant genetic structure exists in seamount and Island populations of precious corals, this could suggest that the elimination (through overharvesting) of a bed of precious corals would result in loss of overall genetic diversity in the species. Here I discuss results based on microsatellite studies of the precious coral, Corallium secundum, from 11 sites in the Hawaiian Archipelago collected between 1998 and 2004, and compare the population genetic structure and dispersal capabilities of Corallium secundum to the results for Corallium lauuense. Microsatellite studies of Corallium lauuense indicated significant heterozygote deficiency in most populations, suggesting recruitment in most populations is from local sources with only occasional long-distance dispersal events. Also, two populations appear to be significantly isolated from other populations of Corallium lauuense and may be separate stocks. In contrast, Corallium secundum populations have little heterozygote deficiency and separate into 3 distinct regions. In addition to having fisheries management implications for these corals, the results of these studies also have implications for the management and protection of seamount fauna.

A bootstrap based space-time surveillance model with an application to crime occurrences

NASA Astrophysics Data System (ADS)

Kim, Youngho; O'Kelly, Morton

2008-06-01

This study proposes a bootstrap-based space-time surveillance model. Designed to find emerging hotspots in near-real time, the bootstrap based model is characterized by its use of past occurrence information and bootstrap permutations. Many existing space-time surveillance methods, using population at risk data to generate expected values, have resulting hotspots bounded by administrative area units and are of limited use for near-real time applications because of the population data needed. However, this study generates expected values for local hotspots from past occurrences rather than population at risk. Also, bootstrap permutations of previous occurrences are used for significant tests. Consequently, the bootstrap-based model, without the requirement of population at risk data, (1) is free from administrative area restriction, (2) enables more frequent surveillance for continuously updated registry database, and (3) is readily applicable to criminology and epidemiology surveillance. The bootstrap-based model performs better for space-time surveillance than the space-time scan statistic. This is shown by means of simulations and an application to residential crime occurrences in Columbus, OH, year 2000.

Detection of sea otters in boat-based surveys of Prince William Sound, Alaska. Marine mammal study 6-19. Exxon Valdez oil spill state/federal natural resource damage assessment final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Udevitz, M.S.; Bodkin, J.L.; Costa, D.P.

1995-05-01

Boat-based surveys were used to monitor the Prince William Sound sea otter population before and after the Exxon Valdez oil spill. Population and loss estimates could be obtained from these surveys by direct expansion from the counts in the surveyed transects under the assumption that all otters in those transects were observed. The authors conducted a pilot study using ground-based observers in conjunction with the August 1990 survey of marine mammals and birds to investigate the validity of this assumption. The proportion of otters detected by boat crews was estimated by comparing boat and ground-based observations on 22 segments ofmore » shoreline transects. Overall, the authors estimated that only 70% of the otters in surveyed shoreline transects were detected by the boat crews. These results suggest that unadjusted expansions of boat survey transect counts will underestimate sea otter population size and that loss estimates based on comparisons of unadjusted population estimates will be biased.« less

Inheritance of Mesotrione Resistance in an Amaranthus tuberculatus (var. rudis) Population from Nebraska, USA

PubMed Central

Oliveira, Maxwel C.; Gaines, Todd A.; Jhala, Amit J.; Knezevic, Stevan Z.

2018-01-01

A population of Amaranthus tuberculatus (var. rudis) evolved resistance to 4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitor herbicides (mesotrione, tembotrione, and topramezone) in Nebraska. The level of resistance was the highest to mesotrione, and the mechanism of resistance in this population is metabolism-based likely via cytochrome P450 enzymes. The increasing number of weeds resistant to herbicides warrants studies on the ecology and evolutionary factors contributing for resistance evolution, including inheritance of resistance traits. In this study, we investigated the genetic control of mesotrione resistance in an A. tuberculatus population from Nebraska, USA. Results showed that reciprocal crosses in the F1 families exhibited nuclear inheritance, which allows pollen movement carrying herbicide resistance alleles. The mode of inheritance varied from incomplete recessive to incomplete dominance depending upon the F1 family. Observed segregation patterns for the majority of the F2 and back-cross susceptible (BC/S) families did not fit to a single major gene model. Therefore, multiple genes are likely to confer metabolism-based mesotrione resistance in this A. tuberculatus population from Nebraska. The results of this study aid to understand the genetics and inheritance of a non-target-site based mesotrione resistant A. tuberculatus population from Nebraska, USA. PMID:29456544

Inequalities in neighbourhood socioeconomic characteristics: potential evidence-base for neighbourhood health planning

PubMed Central

Odoi, Agricola; Wray, Ron; Emo, Marion; Birch, Stephen; Hutchison, Brian; Eyles, John; Abernathy, Tom

2005-01-01

Background Population health planning aims to improve the health of the entire population and to reduce health inequities among population groups. Socioeconomic factors are increasingly being recognized as major determinants of many aspects of health and causes of health inequities. Knowledge of socioeconomic characteristics of neighbourhoods is necessary to identify their unique health needs and enhance identification of socioeconomically disadvantaged populations. Careful integration of this knowledge into health planning activities is necessary to ensure that health planning and service provision are tailored to unique neighbourhood population health needs. In this study, we identify unique neighbourhood socioeconomic characteristics and classify the neighbourhoods based on these characteristics. Principal components analysis (PCA) of 18 socioeconomic variables was used to identify the principal components explaining most of the variation in socioeconomic characteristics across the neighbourhoods. Cluster analysis was used to classify neighbourhoods based on their socioeconomic characteristics. Results Results of the PCA and cluster analysis were similar but the latter were more objective and easier to interpret. Five neighbourhood types with distinguishing socioeconomic and demographic characteristics were identified. The methodology provides a more complete picture of the neighbourhood socioeconomic characteristics than when a single variable (e.g. income) is used to classify neighbourhoods. Conclusion Cluster analysis is useful for generating neighbourhood population socioeconomic and demographic characteristics that can be useful in guiding neighbourhood health planning and service provision. This study is the first of a series of studies designed to investigate health inequalities at the neighbourhood level with a view to providing evidence-base for health planners, service providers and policy makers to help address health inequity issues at the neighbourhood level. Subsequent studies will investigate inequalities in health outcomes both within and across the neighbourhood types identified in the current study. PMID:16092969

Recent range expansion of a terrestrial orchid corresponds with climate-driven variation in its population dynamics.

PubMed

van der Meer, Sascha; Jacquemyn, Hans; Carey, Peter D; Jongejans, Eelke

2016-06-01

The population dynamics and distribution limits of plant species are predicted to change as the climate changes. However, it remains unclear to what extent climate variables affect population dynamics, which vital rates are most sensitive to climate change, and whether the same vital rates drive population dynamics in different populations. In this study, we used long-term demographic data from two populations of the terrestrial orchid Himantoglossum hircinum growing at the northern edge of their geographic range to quantify the influence of climate change on demographic vital rates. Integral projection models were constructed to study how climate conditions between 1991 and 2006 affected population dynamics and to assess how projected future climate change will affect the long-term viability of this species. Based on the parameterised vital rate functions and the observed climatic conditions, one of the studied populations had an average population growth rate above 1 (λ = 1.04), while the other was declining at ca. 3 % year(-1) (λ = 0.97). Variation in temperature and precipitation mainly affected population growth through their effect on survival and fecundity. Based on UK Climate Projection 2009 estimates of future climate conditions for three greenhouse gas emission scenarios, population growth rates are expected to increase in one of the studied populations. Overall, our results indicate that the observed changes in climatic conditions appeared to be beneficial to the long-term survival of the species in the UK and suggest that they may have been the driving force behind the current range expansion of H. hircinum in England.

An integrated modeling approach to estimating Gunnison Sage-Grouse population dynamics: combining index and demographic data.

USGS Publications Warehouse

Davis, Amy J.; Hooten, Mevin B.; Phillips, Michael L.; Doherty, Paul F.

2014-01-01

Evaluation of population dynamics for rare and declining species is often limited to data that are sparse and/or of poor quality. Frequently, the best data available for rare bird species are based on large-scale, population count data. These data are commonly based on sampling methods that lack consistent sampling effort, do not account for detectability, and are complicated by observer bias. For some species, short-term studies of demographic rates have been conducted as well, but the data from such studies are typically analyzed separately. To utilize the strengths and minimize the weaknesses of these two data types, we developed a novel Bayesian integrated model that links population count data and population demographic data through population growth rate (λ) for Gunnison sage-grouse (Centrocercus minimus). The long-term population index data available for Gunnison sage-grouse are annual (years 1953–2012) male lek counts. An intensive demographic study was also conducted from years 2005 to 2010. We were able to reduce the variability in expected population growth rates across time, while correcting for potential small sample size bias in the demographic data. We found the population of Gunnison sage-grouse to be variable and slightly declining over the past 16 years.

The Impact of Selection, Gene Conversion, and Biased Sampling on the Assessment of Microbial Demography.

PubMed

Lapierre, Marguerite; Blin, Camille; Lambert, Amaury; Achaz, Guillaume; Rocha, Eduardo P C

2016-07-01

Recent studies have linked demographic changes and epidemiological patterns in bacterial populations using coalescent-based approaches. We identified 26 studies using skyline plots and found that 21 inferred overall population expansion. This surprising result led us to analyze the impact of natural selection, recombination (gene conversion), and sampling biases on demographic inference using skyline plots and site frequency spectra (SFS). Forward simulations based on biologically relevant parameters from Escherichia coli populations showed that theoretical arguments on the detrimental impact of recombination and especially natural selection on the reconstructed genealogies cannot be ignored in practice. In fact, both processes systematically lead to spurious interpretations of population expansion in skyline plots (and in SFS for selection). Weak purifying selection, and especially positive selection, had important effects on skyline plots, showing patterns akin to those of population expansions. State-of-the-art techniques to remove recombination further amplified these biases. We simulated three common sampling biases in microbiological research: uniform, clustered, and mixed sampling. Alone, or together with recombination and selection, they further mislead demographic inferences producing almost any possible skyline shape or SFS. Interestingly, sampling sub-populations also affected skyline plots and SFS, because the coalescent rates of populations and their sub-populations had different distributions. This study suggests that extreme caution is needed to infer demographic changes solely based on reconstructed genealogies. We suggest that the development of novel sampling strategies and the joint analyzes of diverse population genetic methods are strictly necessary to estimate demographic changes in populations where selection, recombination, and biased sampling are present. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Defining Primary Care Shortage Areas: Do GIS-based Measures Yield Different Results?

PubMed

Daly, Michael R; Mellor, Jennifer M; Millones, Marco

2018-02-12

To examine whether geographic information systems (GIS)-based physician-to-population ratios (PPRs) yield determinations of geographic primary care shortage areas that differ from those based on bounded-area PPRs like those used in the Health Professional Shortage Area (HPSA) designation process. We used geocoded data on primary care physician (PCP) locations and census block population counts from 1 US state to construct 2 shortage area indicators. The first is a bounded-area shortage indicator defined without GIS methods; the second is a GIS-based measure that measures the populations' spatial proximity to PCP locations. We examined agreement and disagreement between bounded shortage areas and GIS-based shortage areas. Bounded shortage area indicators and GIS-based shortage area indicators agree for the census blocks where the vast majority of our study populations reside. Specifically, 95% and 98% of the populations in our full and urban samples, respectively, reside in census blocks where the 2 indicators agree. Although agreement is generally high in rural areas (ie, 87% of the rural population reside in census blocks where the 2 indicators agree), agreement is significantly lower compared to urban areas. One source of disagreement suggests that bounded-area measures may "overlook" some shortages in rural areas; however, other aspects of the HPSA designation process likely mitigate this concern. Another source of disagreement arises from the border-crossing problem, and it is more prevalent. The GIS-based PPRs we employed would yield shortage area determinations that are similar to those based on bounded-area PPRs defined for Primary Care Service Areas. Disagreement rates were lower than previous studies have found. © 2018 National Rural Health Association.

SSR and morphological trait based population structure analysis of 130 diverse flax (Linum usitatissimum L.) accessions.

PubMed

Choudhary, Shashi Bhushan; Sharma, Hariom Kumar; Kumar, Arroju Anil; Maruthi, Rangappa Thimmaiah; Mitra, Jiban; Chowdhury, Isholeena; Singh, Binay Kumar; Karmakar, Pran Gobinda

2017-02-01

A total of 130 flax accessions of diverse morphotypes and worldwide origin were assessed for genetic diversity and population structure using 11 morphological traits and microsatellite markers (15 gSSRs and 7 EST-SSRs). Analysis performed after classifying these accessions on the basis of plant height, branching pattern, seed size, Indian/foreign origin into six categories called sub-populations viz. fibre type exotic, fibre type indigenous, intermediate type exotic, intermediate type indigenous, linseed type exotic and linseed type indigenous. The study assessed different diversity indices, AMOVA, population structure and included a principal coordinate analysis based on different marker systems. The highest diversity was exhibited by gSSR markers (SI=0.46; He=0.31; P=85.11). AMOVA based on all markers explained significant difference among fibre type, intermediate type and linseed type populations of flax. In terms of variation explained by different markers, EST-SSR markers (12%) better differentiated flax populations compared to morphological (9%) and gSSR (6%) markers at P=0.01. The maximum Nei's unbiased genetic distance (D=0.11) was observed between fibre type and linseed type exotic sub-populations based on EST-SSR markers. The combined structure analysis by using all markers grouped Indian fibre type accessions (63.4%) in a separate cluster along with the Indian intermediate type (48.7%), whereas Indian accessions (82.16%) of linseed type constituted an independent cluster. These findings were supported by the results of the principal coordinate analysis. Morphological markers employed in the study found complementary with microsatellite based markers in deciphering genetic diversity and population structure of the flax germplasm. Copyright © 2016 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.

The Combined Burden of Cognitive, Executive Function, and Psychosocial Problems in Children with Epilepsy: A Population-Based Study

ERIC Educational Resources Information Center

Hoie, B.; Sommerfelt, K.; Waaler, P. E.; Alsaker, F. D.; Skeidsvoll, H.; Mykletun, A.

2008-01-01

The combined burden of psychosocial (Achenbach scales), cognitive (Raven matrices), and executive function (EF) problems was studied in a population-based sample of 6- to 12-year-old children with epilepsy (n = 162; 99 males, 63 females) and in an age- and sex-matched control group (n = 107; 62 males, 45 females). Approximately 35% of the children…

Sixteen-Year Change in Acoustic-Admittance Measures among Older Adults: Data from a Population-Based Study

ERIC Educational Resources Information Center

Nondahl, David M.; Cruickshanks, Karen J.; Wiley, Terry L.; Tweed, Ted S.; Dalton, Dayna S.

2013-01-01

Purpose: The primary purpose of this study was to measure the 16-year change in peak compensated static acoustic admittance (Peak Y[subscript tm]) in a population-based cohort of older adults, and to determine whether age was associated with any observed change in Peak Y[subscript tm]. Other tympanometric measures also were taken and analyzed.…

Evidenced-Based Treatment of Depression in the College Population

ERIC Educational Resources Information Center

Lee, Carolyn L.

2005-01-01

This review explores evidence-based treatment for depression within the college and university population. Treatments for depression in adults are among the most rigorous studied treatment modalities in the psychotherapy literature, providing consistent evidence for the efficacy of at least two treatments, cognitive behavioral therapy and…

Cross-cultural estimation of the human generation interval for use in genetics-based population divergence studies.

PubMed

Fenner, Jack N

2005-10-01

The length of the human generation interval is a key parameter when using genetics to date population divergence events. However, no consensus exists regarding the generation interval length, and a wide variety of interval lengths have been used in recent studies. This makes comparison between studies difficult, and questions the accuracy of divergence date estimations. Recent genealogy-based research suggests that the male generation interval is substantially longer than the female interval, and that both are greater than the values commonly used in genetics studies. This study evaluates each of these hypotheses in a broader cross-cultural context, using data from both nation states and recent hunter-gatherer societies. Both hypotheses are supported by this study; therefore, revised estimates of male, female, and overall human generation interval lengths are proposed. The nearly universal, cross-cultural nature of the evidence justifies using these proposed estimates in Y-chromosomal, mitochondrial, and autosomal DNA-based population divergence studies.

Optimizing the creation of base populations for aquaculture breeding programs using phenotypic and genomic data and its consequences on genetic progress.

PubMed

Fernández, Jesús; Toro, Miguel Á; Sonesson, Anna K; Villanueva, Beatriz

2014-01-01

The success of an aquaculture breeding program critically depends on the way in which the base population of breeders is constructed since all the genetic variability for the traits included originally in the breeding goal as well as those to be included in the future is contained in the initial founders. Traditionally, base populations were created from a number of wild strains by sampling equal numbers from each strain. However, for some aquaculture species improved strains are already available and, therefore, mean phenotypic values for economically important traits can be used as a criterion to optimize the sampling when creating base populations. Also, the increasing availability of genome-wide genotype information in aquaculture species could help to refine the estimation of relationships within and between candidate strains and, thus, to optimize the percentage of individuals to be sampled from each strain. This study explores the advantages of using phenotypic and genome-wide information when constructing base populations for aquaculture breeding programs in terms of initial and subsequent trait performance and genetic diversity level. Results show that a compromise solution between diversity and performance can be found when creating base populations. Up to 6% higher levels of phenotypic performance can be achieved at the same level of global diversity in the base population by optimizing the selection of breeders instead of sampling equal numbers from each strain. The higher performance observed in the base population persisted during 10 generations of phenotypic selection applied in the subsequent breeding program.

Measuring informed choice in population-based reproductive genetic screening: a systematic review

PubMed Central

Ames, Alice Grace; Metcalfe, Sylvia Ann; Archibald, Alison Dalton; Duncan, Rony Emily; Emery, Jon

2015-01-01

Genetic screening and health-care guidelines recommend that programmes should facilitate informed choice. It is therefore important that accurate measures of informed choice are available to evaluate such programmes. This review synthesises and appraises measures used to evaluate informed choice in population-based genetic screening programmes for reproductive risk. Databases were searched for studies offering genetic screening for the purpose of establishing reproductive risk to an adult population sample, in which aspects of informed choice were measured. Studies were included if, at a minimum, measures of uptake of screening and knowledge were used. Searches identified 1462 citations and 76 studies were reviewed in full text; 34 studies met the inclusion criteria. Over 20 different measures of informed choice were used. Many measures lacked adequate validity and reliability data. This systematic review will inform future evaluation of informed choice in population genetic screening programmes. PMID:24848746

Clinical reasoning and population health: decision making for an emerging paradigm of health care.

PubMed

Edwards, Ian; Richardson, Barbara

2008-01-01

Chronic conditions now provide the major disease and disability burden facing humanity. This development has necessitated a reorientation in the practice skills of health care professions away from hospital-based inpatient and outpatient care toward community-based management of patients with chronic conditions. Part of this reorientation toward community-based management of chronic conditions involves practitioners' understanding and adoption of a concept of population health management based on appropriate theoretical models of health care. Drawing on recent studies of expertise in physiotherapy, this article proposes a clinical reasoning and decision-making framework to meet these challenges. The challenge of population and community-based management of chronic conditions also provides an opportunity for physiotherapists to further clarify a professional epistemology of practice that embraces the kinds of knowledge and clinical reasoning processes used in physiotherapy practice. Three case studies related to the management of chronic musculoskeletal pain in different populations are used to exemplify the range of epistemological perspectives that underpin community-based practice. They illustrate the link between conceptualizations of practice problems and knowledge sources that are used as a basis for clinical reasoning and decision making as practitioners are increasingly required to move between the clinic and the community.

Prevalence of chlamydia, gonorrhoea, syphilis and trichomonas in Aboriginal and Torres Strait Islander Australians: a systematic review and meta-analysis.

PubMed

Graham, Simon; Smith, Lucy Watchirs; Fairley, Christopher K; Hocking, Jane

2016-04-01

Higher notification rates of sexually transmissible infections (STIs) are reported among Aboriginal and Torres Strait Islander (Aboriginal) compared with non-Aboriginal people in Australia. The aim of this study is to estimate the pooled prevalence of chlamydia, gonorrhoea, syphilis and trichomonas among Aboriginal people in Australia by sex, age-group, setting (clinic vs population/community-based) and population group [adults, pregnant females, young people (12-29 years) and prisoners]. The databases Medline, PubMed and Web of Science were searched in May 2015. A meta-analysis was conducted to estimate the pooled prevalence of the four STIs in Aboriginal people and if possible, by gender, age-group, setting and population group. A total of 46 studies were included. The pooled prevalence was 11.2% (95%CI: 9.4-13.0%) for chlamydia (36 studies), 12.5% (95%CI: 10.5-14.6%) for gonorrhoea (28 studies), 16.8% (95%CI: 11.0-22.6%) for syphilis (13 studies) and 22.6% (95%CI: 18.5-26.7%) for trichomonas (11 studies); however, there was significant heterogeneity between studies (I(2) <97.5%, P<0.01). In the subgroup analysis, a higher pooled prevalence occurred in females than males for chlamydia (12.7% vs 7.7%) and gonorrhoea (10.7% vs 8.1%). The prevalence of chlamydia was 12.4% in clinic-based compared with 4.3% in population-based studies. The highest pooled prevalence by population group was among pregnant females (16.8%) and young people (16.2%) for chlamydia, pregnant females (25.2%) for trichomonas; and young people for gonorrhoea (11.9%). This review highlights the need to decrease the prevalence of STIs among Aboriginal people through community-based programs that target asymptomatic young people.

Resilience of aging populations after devastating earthquake event and its determinants - A case study of the Chi-Chi earthquake in Taiwan

NASA Astrophysics Data System (ADS)

Hung, Chih-Hsuan; Hung, Hung-Chih

2016-04-01

1.Background Major portions of urban areas in Asia are highly exposed and vulnerable to devastating earthquakes. Many studies identify ways to reduce earthquake risk by concentrating more on building resilience for the particularly vulnerable populations. By 2020, as the United Nations' warning, many Asian countries would become 'super-aged societies', such as Taiwan. However, local authorities rarely use resilience approach to frame earthquake disaster risk management and land use strategies. The empirically-based research about the resilience of aging populations has also received relatively little attention. Thus, a challenge arisen for decision-makers is how to enhance resilience of aging populations within the context of risk reduction. This study aims to improve the understanding of the resilience of aging populations and its changes over time in the aftermath of a destructive earthquake at the local level. A novel methodology is proposed to assess the resilience of aging populations and to characterize their changes of spatial distribution patterns, as well as to examine their determinants. 2.Methods and data An indicator-based assessment framework is constructed with the goal of identifying composite indicators (including before, during and after a disaster) that could serve as proxies for attributes of the resilience of aging populations. Using the recovery process of the Chi-Chi earthquake struck central Taiwan in 1999 as a case study, we applied a method combined a geographical information system (GIS)-based spatial statistics technique and cluster analysis to test the extent of which the resilience of aging populations is spatially autocorrelated throughout the central Taiwan, and to explain why clustering of resilient areas occurs in specific locations. Furthermore, to scrutinize the affecting factors of resilience, we develop an aging population resilience model (APRM) based on existing resilience theory. Using the APRM, we applied a multivariate regression analysis to identify and examine how various factors connect to the resilience of aging populations. To illustrate the proposed methodology, the study collected data on the resilience attributes, the disaster impacts and damages due to the Chi-Chi earthquake. The data were offered by the National Science and Technology Center for Disaster Reduction, Taiwan, as well as collected from the National Land Use Investigation, official census statistics and questionnaire surveys. 3.Results Integrating cluster analysis with GIS-based spatial statistical analysis, the resilience of aging populations were divided into five clusters of distribution patterns over the 10 years after the Chi-Chi earthquake. It shows that both population and elderly distributions were highly heterogeneous and spatial correlated across the study areas. We also demonstrated the 'hot spots' areas of the highly concentrated aging population across central Taiwan. Results of regression analysis disclosed the major factors that caused low resilience and changes of aging population distributions over time. These factors included the levels of seismic damage, infrastructure investments, as well as the land-use and socioeconomic attributes associated with the disaster areas. Finally, our findings provide stakeholders and policy-makers with better adaptive options to design and synthesize appropriate patchworks of planning measures for different types of resilience areas to reduce earthquake disaster risk.

Vitamin K status and vascular calcification: evidence from observational and clinical studies.

PubMed

Shea, M Kyla; Holden, Rachel M

2012-03-01

Vascular calcification occurs when calcium accumulates in the intima (associated with atherosclerosis) and/or media layers of the vessel wall. Coronary artery calcification (CAC) reflects the calcium burden within the intima and media of the coronary arteries. In population-based studies, CAC independently predicts cardiovascular disease (CVD) and mortality. A preventive role for vitamin K in vascular calcification has been proposed based on its role in activating matrix Gla protein (MGP), a calcification inhibitor that is expressed in vascular tissue. Although animal and in vitro data support this role of vitamin K, overall data from human studies are inconsistent. The majority of population-based studies have relied on vitamin K intake to measure status. Phylloquinone is the primary dietary form of vitamin K and available supplementation trials, albeit limited, suggest phylloquinone supplementation is relevant to CAC. Yet observational studies have found higher dietary menaquinone, but not phylloquinone, to be associated with less calcification. Vascular calcification is highly prevalent in certain patient populations, especially in those with chronic kidney disease (CKD), and it is plausible vitamin K may contribute to reducing vascular calcification in patients at higher risk. Subclinical vitamin K deficiency has been reported in CKD patients, but studies linking vitamin K status to calcification outcomes in CKD are needed to clarify whether or not improving vitamin K status is associated with improved vascular health in CKD. This review summarizes the available evidence of vitamin K and vascular calcification in population-based studies and clinic-based studies, with a specific focus on CKD patients.

Comparative analysis of premature mortality among urban immigrants in Bremen, Germany: a retrospective register-based linkage study.

PubMed

Makarova, Nataliya; Brand, Tilman; Brünings-Kuppe, Claudia; Pohlabeln, Hermann; Luttmann, Sabine

2016-03-21

The main objective of this study was to explore differences in mortality patterns among two large immigrant groups in Germany: one from Turkey and the other from the former Soviet Union (FSU). To this end, we investigated indicators of premature mortality. This study was conducted as a retrospective population-based study based on mortality register linkage. Using mortality data for the period 2004-2010, we calculated age-standardised death rates (SDR) and standardised mortality ratios (SMR) for premature deaths (

Comparative analysis of premature mortality among urban immigrants in Bremen, Germany: a retrospective register-based linkage study

PubMed Central

Makarova, Nataliya; Brand, Tilman; Brünings-Kuppe, Claudia; Pohlabeln, Hermann; Luttmann, Sabine

2016-01-01

Objectives The main objective of this study was to explore differences in mortality patterns among two large immigrant groups in Germany: one from Turkey and the other from the former Soviet Union (FSU). To this end, we investigated indicators of premature mortality. Design This study was conducted as a retrospective population-based study based on mortality register linkage. Using mortality data for the period 2004–2010, we calculated age-standardised death rates (SDR) and standardised mortality ratios (SMR) for premature deaths (

Insurance problems among inflammatory bowel disease patients: results of a Dutch population based study.

PubMed

Russel, M G V M; Ryan, B M; Dagnelie, P C; de Rooij, M; Sijbrandij, J; Feleus, A; Hesselink, M; Muris, J W; Stockbrugger, R

2003-03-01

The majority of patients with inflammatory bowel disease (IBD) have a normal life expectancy and therefore should not be weighted when applying for life assurance. There is scant literature on this topic. In this study our aim was to document and compare the incidence of difficulties in application for life and medical insurance in a population based cohort of IBD patients and matched population controls. A population based case control study of 1126 IBD patients and 1723 controls. Based on a detailed questionnaire, the frequency and type of difficulties encountered when applying for life and medical insurance in matched IBD and control populations were appraised. In comparison with controls, IBD patients had an 87-fold increased risk of encountering difficulties when applying for life assurance (odds ratio (OR) 87 (95% confidence interval (CI) 31-246)), with a heavily weighted premium being the most common problem. Patients of high educational status, with continuous disease activity, and who smoked had the highest odds of encountering such problems. Medical insurance difficulties were fivefold more common in IBD patients compared with controls (OR 5.4 (95% CI 2.3-13)) although no specific disease or patient characteristics were identified as associated with such difficulties. This is the first detailed case control study that has investigated insurance difficulties among IBD patients. Acquiring life and medical insurance constituted a major problem for IBD patients in this study. These results are likely to be more widely representative given that most insurance companies use international guidelines for risk assessment. In view of the recent advances in therapy and promising survival data on IBD patients, evidence based guidelines for risk assessment of IBD patients by insurance companies should be drawn up to prevent possible discriminatory practices.

Insurance problems among inflammatory bowel disease patients: results of a Dutch population based study

PubMed Central

Russel, M G V M; Ryan, B M; Dagnelie, P C; de Rooij, M; Sijbrandij, J; Feleus, A; Hesselink, M; Muris, J W; Stockbrugger, R

2003-01-01

Background and aims: The majority of patients with inflammatory bowel disease (IBD) have a normal life expectancy and therefore should not be weighted when applying for life assurance. There is scant literature on this topic. In this study our aim was to document and compare the incidence of difficulties in application for life and medical insurance in a population based cohort of IBD patients and matched population controls. Methods: A population based case control study of 1126 IBD patients and 1723 controls. Based on a detailed questionnaire, the frequency and type of difficulties encountered when applying for life and medical insurance in matched IBD and control populations were appraised. Results: In comparison with controls, IBD patients had an 87-fold increased risk of encountering difficulties when applying for life assurance (odds ratio (OR) 87 (95% confidence interval (CI) 31–246)), with a heavily weighted premium being the most common problem. Patients of high educational status, with continuous disease activity, and who smoked had the highest odds of encountering such problems. Medical insurance difficulties were fivefold more common in IBD patients compared with controls (OR 5.4 (95% CI 2.3–13)) although no specific disease or patient characteristics were identified as associated with such difficulties. Conclusions: This is the first detailed case control study that has investigated insurance difficulties among IBD patients. Acquiring life and medical insurance constituted a major problem for IBD patients in this study. These results are likely to be more widely representative given that most insurance companies use international guidelines for risk assessment. In view of the recent advances in therapy and promising survival data on IBD patients, evidence based guidelines for risk assessment of IBD patients by insurance companies should be drawn up to prevent possible discriminatory practices. PMID:12584216

A population-based descriptive study of housefire deaths in North Carolina.

PubMed Central

Patetta, M J; Cole, T B

1990-01-01

We report a population-based study of housefire deaths in North Carolina in 1985 using data obtained from fire investigators and the North Carolina medical examiner system. The crude death rate was 3.2 per 100,000 population; age-specific death rates were highest for ages 75-84 years. Death rates for Whites were one-third as high as death rates for other races. Of those decedents tested for alcohol, 56 percent had blood alcohol levels greater than or equal to 22 mmol/L. Most fatal fires were caused by heating units or cigarettes. PMID:2382752

Double Trouble at High Density: Cross-Level Test of Resource-Related Adaptive Plasticity and Crowding-Related Fitness

PubMed Central

Gergs, André; Preuss, Thomas G.; Palmqvist, Annemette

2014-01-01

Population size is often regulated by negative feedback between population density and individual fitness. At high population densities, animals run into double trouble: they might concurrently suffer from overexploitation of resources and also from negative interference among individuals regardless of resource availability, referred to as crowding. Animals are able to adapt to resource shortages by exhibiting a repertoire of life history and physiological plasticities. In addition to resource-related plasticity, crowding might lead to reduced fitness, with consequences for individual life history. We explored how different mechanisms behind resource-related plasticity and crowding-related fitness act independently or together, using the water flea Daphnia magna as a case study. For testing hypotheses related to mechanisms of plasticity and crowding stress across different biological levels, we used an individual-based population model that is based on dynamic energy budget theory. Each of the hypotheses, represented by a sub-model, is based on specific assumptions on how the uptake and allocation of energy are altered under conditions of resource shortage or crowding. For cross-level testing of different hypotheses, we explored how well the sub-models fit individual level data and also how well they predict population dynamics under different conditions of resource availability. Only operating resource-related and crowding-related hypotheses together enabled accurate model predictions of D. magna population dynamics and size structure. Whereas this study showed that various mechanisms might play a role in the negative feedback between population density and individual life history, it also indicated that different density levels might instigate the onset of the different mechanisms. This study provides an example of how the integration of dynamic energy budget theory and individual-based modelling can facilitate the exploration of mechanisms behind the regulation of population size. Such understanding is important for assessment, management and the conservation of populations and thereby biodiversity in ecosystems. PMID:24626228

Temporal Trends in the Utilization of Noninvasive Diagnostic Tests for Coronary Artery Disease in Ontario Between 2008 and 2014: A Population-Based Study.

PubMed

Roifman, Idan; Wijeysundera, Harindra C; Austin, Peter C; Maclagan, Laura C; Rezai, Mohammad R; Wright, Graham A; Tu, Jack V

2017-02-01

The proliferation of cardiac diagnostic tests over the past few decades has received substantial attention from policymakers. However, contemporary population-based temporal trends of the utilization of noninvasive cardiac diagnostic tests for coronary artery disease are not known. Our objective was to examine the temporal trends in the utilization of coronary computed tomography angiography (CCTA), myocardial perfusion imaging (MPI), exercise stress testing (GXT), and stress echocardiography between 2008 and 2014. We performed a population-based repeated cross-sectional study of the adult population of Ontario between January 1, 2008 and December 31, 2014. Annual utilization rates of noninvasive cardiac diagnostic tests were computed. For each cardiac testing modality, a negative binomial regression model was used to assess temporal changes in test utilization. GXT and MPI collectively accounted for 88% of all cardiac noninvasive diagnostic tests throughout our study period. Age- and sex-standardized rates of GXT declined from 26.7/1000 adult population to 21.6/1000 adult population (mean annual reduction of 3.4%; P < 0.001). MPI rates declined from 21.1/1000 adult population to 19.5/1000 adult population (mean annual reduction of 1.3%; P < 0.001). Although utilization rates for both CCTA and stress echocardiography increased over time, the combined rate of all available tests decreased from 50.8/1000 adult population to 49.1/1000 adult population (mean annual reduction of 1.1%; P < 0.001). In conclusion, utilization rates for the most prevalent noninvasive cardiac diagnostic tests-GXT and MPI-declined over our study period. Furthermore, the overall test utilization rate also declined over time. We believe our findings are encouraging from a health policy perspective. Nonetheless, rising utilization rates for CCTA and stress echocardiography will need to be monitored in the future. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Risk of fragility fracture among patients with sarcoidosis: a population-based study 1976-2013-supplementary presentation.

PubMed

Ungprasert, P; Crowson, C S; Matteson, E L

2018-05-01

Incidence of fragility fracture of a population-based cohort of 345 patients with sarcoidosis was compared with age- and sex-matched comparators. The incidence of fragility fracture was higher among patients with sarcoidosis with a hazard ratio (HR) of 2.18.

Development and assessment of plant-based synthetic odor baits for surveillance and control of Malaria vectors

USDA-ARS?s Scientific Manuscript database

Recent malaria vector control measures have considerably reduced indoor biting mosquito populations. However, reducing the outdoor biting populations remains a challenge because of the unavailability of appropriate lures to achieve this. This study sought to test the efficacy of plant-based syntheti...

Molecular Epidemiology of Helicobacter pylori Infection in a Minor Ethnic Group of Vietnam: A Multiethnic, Population-Based Study.

PubMed

Binh, Tran Thanh; Tuan, Vo Phuoc; Dung, Ho Dang Quy; Tung, Pham Huu; Tri, Tran Dinh; Thuan, Ngo Phuong Minh; Tam, Le Quang; Nam, Bui Chi; Giang, Do Anh; Hoan, Phan Quoc; Uchida, Tomohisa; Trang, Tran Thi Huyen; Khien, Vu Van; Yamaoka, Yoshio

2018-03-01

The Helicobacter pylori -induced burden of gastric cancer varies based on geographical regions and ethnic grouping. Vietnam is a multiethnic country with the highest incidence of gastric cancer in Southeast Asia, but previous studies focused only on the Kinh ethnic group. A population-based cross-sectional study was conducted using 494 volunteers (18-78 years old), from 13 ethnic groups in Daklak and Lao Cai provinces, Vietnam. H. pylori status was determined by multiple tests (rapid urease test, culture, histology, and serology). cagA and vacA genotypes were determined by PCR-based sequencing. The overall H. pylori infection rate was 38.1%. Multivariate analysis showed that variations in geographical region, age, and ethnicity were independent factors associated with the risk of H. pylori acquisition. Therefore, multicenter, multiethnic, population based study is essential to assess the H. pylori prevalence and its burden in the general population. Only the E De ethnicity carried strains with Western-type CagA (82%) and exhibited significantly lower gastric mucosal inflammation compared to other ethnic groups. However, the histological scores of Western-type CagA and East-Asian-type CagA within the E De group showed no significant differences. Thus, in addition to bacterial virulence factors, host factors are likely to be important determinants for gastric mucosal inflammation and contribute to the Asian enigma.

Big-Data Based Decision-Support Systems to Improve Clinicians' Cognition.

PubMed

Roosan, Don; Samore, Matthew; Jones, Makoto; Livnat, Yarden; Clutter, Justin

2016-01-01

Complex clinical decision-making could be facilitated by using population health data to inform clinicians. In two previous studies, we interviewed 16 infectious disease experts to understand complex clinical reasoning. For this study, we focused on answers from the experts on how clinical reasoning can be supported by population-based Big-Data. We found cognitive strategies such as trajectory tracking, perspective taking, and metacognition has the potential to improve clinicians' cognition to deal with complex problems. These cognitive strategies could be supported by population health data, and all have important implications for the design of Big-Data based decision-support tools that could be embedded in electronic health records. Our findings provide directions for task allocation and design of decision-support applications for health care industry development of Big data based decision-support systems.

Big-Data Based Decision-Support Systems to Improve Clinicians’ Cognition

PubMed Central

Roosan, Don; Samore, Matthew; Jones, Makoto; Livnat, Yarden; Clutter, Justin

2016-01-01

Complex clinical decision-making could be facilitated by using population health data to inform clinicians. In two previous studies, we interviewed 16 infectious disease experts to understand complex clinical reasoning. For this study, we focused on answers from the experts on how clinical reasoning can be supported by population-based Big-Data. We found cognitive strategies such as trajectory tracking, perspective taking, and metacognition has the potential to improve clinicians’ cognition to deal with complex problems. These cognitive strategies could be supported by population health data, and all have important implications for the design of Big-Data based decision-support tools that could be embedded in electronic health records. Our findings provide directions for task allocation and design of decision-support applications for health care industry development of Big data based decision-support systems. PMID:27990498

Regional Impact of Population Aging on Changes in Individual Self-perceptions of Aging: Findings From the German Ageing Survey.

PubMed

Wolff, Julia K; Beyer, Ann-Kristin; Wurm, Susanne; Nowossadeck, Sonja; Wiest, Maja

2018-01-18

The importance of self-perceptions of aging (SPA) for health and longevity is well documented. Comparably little is known about factors that contribute to SPA. Besides individual factors, the context a person lives in may shape SPA. Research has so far focused on country-level differences in age stereotypes, indicating that rapid population aging accompanies more negative age stereotypes. The present study expands previous research by investigating the impact of district-specific population aging within one country on different facets of SPA. Based on a large representative survey in Germany, the study investigates changes in SPA as ongoing development as well as the SPA of physical loss over a 12-year period in adults aged 40+. The study uses several indicators of population aging (e.g., population development, average age, greying index), to identify four clusters differing in their pace of population aging. Based on three-level latent change models, these clusters were compared in their impact on changes in SPA. Compared to districts with an average rate of population aging, the study shows that persons living in regions with a fast population aging rate (C1) hold more negative SPA in both facets (ps = .01). Districts with slow population aging (C2) have significantly higher SPA ongoing development (p = .03). The study underlines the importance for regional differences in population aging on the development of SPA. In particular, societies should be aware that fast population aging may result in more negative SPA. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kostova, T; Carlsen, T

We present a study, based on simulations with SERDYCA, a spatially-explicit individual-based model of rodent dynamics, on the relation between population persistence and the presence of numerous isolated disturbances in the habitat. We are specifically interested in the effect of disturbances that do not fragment the environment on population persistence. Our results suggest that the presence of disturbances in the absence of fragmentation can actually increase the average time to extinction of the modeled population. The presence of disturbances decreases population density but can increase the chance for mating in monogamous species and consequently, the ratio of juveniles in themore » population. It thus provides a better chance for the population to restore itself after a severe period with critically low population density. We call this the ''disturbance-forced localization effect''.« less

Evaluating sampling designs by computer simulation: A case study with the Missouri bladderpod

USGS Publications Warehouse

Morrison, L.W.; Smith, D.R.; Young, C.; Nichols, D.W.

2008-01-01

To effectively manage rare populations, accurate monitoring data are critical. Yet many monitoring programs are initiated without careful consideration of whether chosen sampling designs will provide accurate estimates of population parameters. Obtaining accurate estimates is especially difficult when natural variability is high, or limited budgets determine that only a small fraction of the population can be sampled. The Missouri bladderpod, Lesquerella filiformis Rollins, is a federally threatened winter annual that has an aggregated distribution pattern and exhibits dramatic interannual population fluctuations. Using the simulation program SAMPLE, we evaluated five candidate sampling designs appropriate for rare populations, based on 4 years of field data: (1) simple random sampling, (2) adaptive simple random sampling, (3) grid-based systematic sampling, (4) adaptive grid-based systematic sampling, and (5) GIS-based adaptive sampling. We compared the designs based on the precision of density estimates for fixed sample size, cost, and distance traveled. Sampling fraction and cost were the most important factors determining precision of density estimates, and relative design performance changed across the range of sampling fractions. Adaptive designs did not provide uniformly more precise estimates than conventional designs, in part because the spatial distribution of L. filiformis was relatively widespread within the study site. Adaptive designs tended to perform better as sampling fraction increased and when sampling costs, particularly distance traveled, were taken into account. The rate that units occupied by L. filiformis were encountered was higher for adaptive than for conventional designs. Overall, grid-based systematic designs were more efficient and practically implemented than the others. ?? 2008 The Society of Population Ecology and Springer.

Coupling Financial Incentives With Direct Mail in Population-Based Practice.

PubMed

Slater, Jonathan S; Parks, Michael J; Malone, Michael E; Henly, George A; Nelson, Christina L

2017-02-01

Financial incentives are being used increasingly to encourage a wide array of health behaviors because of their well-established efficacy. However, little is known about how to translate incentive-based strategies to public health practice geared toward improving population-level health, and a dearth of research exists on how individuals respond to incentives through public health communication strategies such as direct mail. This study reports results of a population-based randomized controlled trial testing a direct mail, incentive-based intervention for promoting mammography uptake. The study population was composed of a random sample of Minnesota women enrolled in Medicare fee-for-service and overdue for breast cancer screening. Participants ( N = 18,939) were randomized into three groups: (1) Direct Mail only, (2) Direct Mail plus Incentive, and (3) Control. Both direct mail groups received two mailers with a message about the importance of mammography; however, Mail plus Incentive mailers also offered a $25 incentive for getting a mammogram. Logistic regression analyses measured intervention effects. Results showed the odds for receiving mammography were significantly higher for the Direct Mail plus Incentive group compared with both Direct Mail only and Control groups. The use of incentives also proved to be cost-effective. Additionally, the Direct Mail only group was more likely to receive mammography than the Control group. Findings offer experimental evidence on how the population-based strategy of direct mail coupled with a financial incentive can encourage healthy behavior, as well as how incentive-based programs can be translated into health promotion practice aimed at achieving population-level impact.

Genomic estimation of additive and dominance effects and impact of accounting for dominance on accuracy of genomic evaluation in sheep populations.

PubMed

Moghaddar, N; van der Werf, J H J

2017-12-01

The objectives of this study were to estimate the additive and dominance variance component of several weight and ultrasound scanned body composition traits in purebred and combined cross-bred sheep populations based on single nucleotide polymorphism (SNP) marker genotypes and then to investigate the effect of fitting additive and dominance effects on accuracy of genomic evaluation. Additive and dominance variance components were estimated in a mixed model equation based on "average information restricted maximum likelihood" using additive and dominance (co)variances between animals calculated from 48,599 SNP marker genotypes. Genomic prediction was based on genomic best linear unbiased prediction (GBLUP), and the accuracy of prediction was assessed based on a random 10-fold cross-validation. Across different weight and scanned body composition traits, dominance variance ranged from 0.0% to 7.3% of the phenotypic variance in the purebred population and from 7.1% to 19.2% in the combined cross-bred population. In the combined cross-bred population, the range of dominance variance decreased to 3.1% and 9.9% after accounting for heterosis effects. Accounting for dominance effects significantly improved the likelihood of the fitting model in the combined cross-bred population. This study showed a substantial dominance genetic variance for weight and ultrasound scanned body composition traits particularly in cross-bred population; however, improvement in the accuracy of genomic breeding values was small and statistically not significant. Dominance variance estimates in combined cross-bred population could be overestimated if heterosis is not fitted in the model. © 2017 Blackwell Verlag GmbH.

Understanding human DNA sequence variation.

PubMed

Kidd, K K; Pakstis, A J; Speed, W C; Kidd, J R

2004-01-01

Over the past century researchers have identified normal genetic variation and studied that variation in diverse human populations to determine the amounts and distributions of that variation. That information is being used to develop an understanding of the demographic histories of the different populations and the species as a whole, among other studies. With the advent of DNA-based markers in the last quarter century, these studies have accelerated. One of the challenges for the next century is to understand that variation. One component of that understanding will be population genetics. We present here examples of many of the ways these new data can be analyzed from a population perspective using results from our laboratory on multiple individual DNA-based polymorphisms, many clustered in haplotypes, studied in multiple populations representing all major geographic regions of the world. These data support an "out of Africa" hypothesis for human dispersal around the world and begin to refine the understanding of population structures and genetic relationships. We are also developing baseline information against which we can compare findings at different loci to aid in the identification of loci subject, now and in the past, to selection (directional or balancing). We do not yet have a comprehensive understanding of the extensive variation in the human genome, but some of that understanding is coming from population genetics.

Dioecy in Amborella trichopoda: evidence for genetically based sex determination and its consequences for inferences of the breeding system in early angiosperms.

PubMed

Anger, Nicolas; Fogliani, Bruno; Scutt, Charles P; Gâteblé, Gildas

2017-03-01

This work aimed to gain insight into the breeding system at the base of living angiosperms through both character state reconstructions and the study of sex ratios and phenotypes in the likely sister to all other living angiosperms, Amborella trichopoda . Sex phenotypes were mapped onto a phylogeny of basally diverging angiosperms using maximum parsimony. In parallel, sex ratios and phenotypes were studied over two consecutive flowering seasons in an ex situ population of A. trichopoda , while the sex ratio of an in situ population was also assessed. Parsimony analyses failed to resolve the breeding system present at the base of living angiosperms, but indicated the importance of A. trichopoda for the future elucidation of this question. The ex situ A. trichopoda population studied showed a primary sex ratio close to 1:1, though sex ratio bias was found in the in situ population studied. Instances of sexual instability were quantified in both populations. Sex ratio data support the presence of genetic sex determination in A. trichopoda , whose further elucidation may guide inferences on the breeding system at the base of living angiosperms. Sexual instability in A. trichopoda suggests the operation of epigenetic mechanisms, and the evolution of dioecy via a gynodioecious intermediate. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Genetic variation and forensic characteristic analysis of 25 STRs of a novel fluorescence co-amplification system in Chinese Southern Shaanxi Han population

PubMed Central

Liu, Yao-Shun; Chen, Jian-Gang; Mei, Ting; Guo, Yu-Xin; Meng, Hao-Tian; Li, Jian-Fei; Wei, Yuan-Yuan; Jin, Xiao-Ye; Zhu, Bo-Feng; Zhang, Li-Ping

2017-01-01

We analyzed the genetic polymorphisms of 15 autosomal and 10 Y-chromosomal STR loci in 214 individuals of Han population from Southern Shaanxi of China and studied the genetic relationships between Southern Shaanxi Han and other populations. We observed a total of 150 alleles at 15 autosomal STR loci with the corresponding allelic frequencies ranging from 0.0023 to 0.5210, and the combined power of discrimination and exclusion for the 15 autosomal STR loci were 0.99999999999999998866 and 0.999998491, respectively. For the 10 Y-STR loci, totally 100 different haplotypes were obtained, of which 94 were unique. The discriminatory capacity and haplotype diversity values of the 10 Y-STR loci were 0.9259 and 0.998269, respectively. The results demonstrated high genetic diversities of the 25 STR loci in the population for forensic applications. We constructed neighbor-joining tree and conducted principal component analysis based on 15 autosomal STR loci and conducted multidimensional scaling analysis and constructed neighbor-joining tree based on 10 Y-STR loci. The results of population genetic analyses based on both autosomal and Y-chromosome STRs indicated that the studied Southern Shaanxi Han population had relatively closer genetic relationship with Eastern Han population, and distant relationships with Croatian, Serbian and Moroccan populations. PMID:28903432

Polar bear aerial survey in the eastern Chukchi Sea: A pilot study

USGS Publications Warehouse

Evans, Thomas J.; Fischbach, Anthony S.; Schliebe, Scott L.; Manly, Bryan; Kalxdorff, Susanne B.; York, Geoff S.

2003-01-01

Alaska has two polar bear populations: the Southern Beaufort Sea population, shared with Canada, and the Chukchi/Bering Seas population, shared with Russia. Currently a reliable population estimate for the Chukchi/Bering Seas population does not exist. Land-based aerial and mark-recapture population surveys may not be possible in the Chukchi Sea because variable ice conditions, the limited range of helicopters, extremely large polar bear home ranges, and severe weather conditions may limit access to remote areas. Thus line-transect aerial surveys from icebreakers may be the best available tool to monitor this polar bear stock. In August 2000, a line-transect survey was conducted in the eastern Chukchi Sea and western Beaufort Sea from helicopters based on a U.S. Coast Guard icebreaker under the "Ship of Opportunity" program. The objectives of this pilot study were to estimate polar bear density in the eastern Chukchi and western Beaufort Seas and to assess the logistical feasibility of using ship-based aerial surveys to develop polar bear population estimates. Twenty-nine polar bears in 25 groups were sighted on 94 transects (8257 km). The density of bears was estimated as 1 bear per 147 km² (CV = 38%). Additional aerial surveys in late fall, using dedicated icebreakers, would be required to achieve the number of sightings, survey effort, coverage, and precision needed for more effective monitoring of population trends in the Chukchi Sea.

A Population-Based Study of Dietary Acrylamide and Prostate Cancer Risk

DTIC Science & Technology

2006-03-01

159 microgram/day. 3. The four food products that contributed the most to the total intake of acrylamide among controls were crisp bread, coffee ... Acrylamide and Prostate Cancer Risk PRINCIPLE INVESTIGATOR: Hans-Olov Adami, M.D., Ph.D. CONTRACTING ORGANIZATION: Karolinska...NUMBER A Population-Based Study of Dietary Acrylamide and Prostate Cancer Risk 5b. GRANT NUMBER W81XWH-04-1-0288 5c. PROGRAM ELEMENT NUMBER

In response to the December 2016 article entitled "Vegetarian diet and all-cause mortality: Evidence from a large population-based Australian cohort - the 45 and Up Study".

PubMed

Taylor, Nathan G A

2017-07-01

In response to the December 2016 article entitled "Vegetarian diet and all-cause mortality: Evidence from a large population-based Australian cohort - the 45 and Up Study". A brief analysis of the article with suggestions for interpretation and considerations for future research. Copyright © 2017 Elsevier Inc. All rights reserved.

Population genetic analysis of Enterocytozoon bieneusi in humans.

PubMed

Li, Wei; Cama, Vitaliano; Feng, Yaoyu; Gilman, Robert H; Bern, Caryn; Zhang, Xichen; Xiao, Lihua

2012-01-01

Genotyping based on sequence analysis of the ribosomal internal transcribed spacer has revealed significant genetic diversity in Enterocytozoonbieneusi. Thus far, the population genetics of E. bieneusi and its significance in the epidemiology of microsporidiosis have not been examined. In this study, a multilocus sequence typing of E. bieneusi in AIDS patients in Lima, Peru was conducted, using 72 specimens previously genotyped as A, D, IV, EbpC, WL11, Peru7, Peru8, Peru10 and Peru11 at the internal transcribed spacer locus. Altogether, 39 multilocus genotypes were identified among the 72 specimens. The observation of strong intragenic linkage disequilibria and limited genetic recombination among markers were indicative of an overall clonal population structure of E. bieneusi. Measures of pair-wise intergenic linkage disequilibria and a standardised index of association (IAS) based on allelic profile data further supported this conclusion. Both sequence-based and allelic profile-based phylogenetic analyses showed the presence of two genetically isolated groups in the study population, one (group 1) containing isolates of the anthroponotic internal transcribed spacer genotype A, and the other (group 2) containing isolates of multiple internal transcribed spacer genotypes (mainly genotypes D and IV) with zoonotic potential. The measurement of linkage disequilibria and recombination indicated group 2 had a clonal population structure, whereas group 1 had an epidemic population structure. The formation of the two sub-populations was confirmed by STRUCTURE and Wright's fixation index (FST) analyses. The data highlight the power of MLST in understanding the epidemiology of E. bieneusi. Published by Elsevier Ltd.

Static metrics of impact for a dynamic problem: The need for smarter tools to guide suicide prevention planning and investment.

PubMed

Page, Andrew; Atkinson, Jo-An; Heffernan, Mark; McDonnell, Geoff; Prodan, Ante; Osgood, Nathaniel; Hickie, Ian

2018-01-01

This study investigates two approaches to estimate the potential impact of a population-level intervention on Australian suicide, to highlight the importance of selecting appropriate analytic approaches for informing evidence-based strategies for suicide prevention. The potential impact of a psychosocial therapy intervention on the incidence of suicide in Australia over the next 10 years was used as a case study to compare the potential impact on suicides averted using: (1) a traditional epidemiological measure of population attributable risk and (2) a dynamic measure of population impact based on a systems science model of suicide that incorporates changes over time. Based on the population preventive fraction, findings suggest that the psychosocial therapy intervention if implemented among all eligible individuals in the Australian population would prevent 5.4% of suicides (or 1936 suicides) over the next 10 years. In comparison, estimates from the dynamic simulation model which accounts for changes in the effect size of the intervention over time, the time taken for the intervention to have an impact in the population, and likely barriers to the uptake and availability of services suggest that the intervention would avert a lower proportion of suicides (between 0.4% and 0.5%) over the same follow-up period. Traditional epidemiological measures used to estimate population health burden have several limitations that are often understated and can lead to unrealistic expectations of the potential impact of evidence-based interventions in real-world settings. This study highlights these limitations and proposes an alternative analytic approach to guide policy and practice decisions to achieve reductions in Australian suicide.

Short-term population-based and spatiotemporal nonlinear concentration-response associations between fine particulate matter and children's respiratory clinic visits

NASA Astrophysics Data System (ADS)

Yu, Hwa-Lung; Chien, Lung-Chang

2014-05-01

Advert health impacts associated with the PM2.5 exposure have been confirmed in mortality and cardiovascular diseases; however, findings of the influence of PM2.5 on respiratory diseases investigated among previous studies are still inconsistent. We investigated the short-term population-based associations between the respiratory clinic visits of children population and the PM2.5 exposure levels with considering both the spatiotemporal distributions of the ambient pollution and clinic visit data. We applied a spatiotemporal structured additive regression model to examine the concentration-response (C-R) association between daily children's respiratory clinic visits and PM2.5 concentrations. The analysis was performed separately on the four selected respiratory disease categories of the population-based dataset, obtained from Taiwan National Health Insurance database, covering the 41 districts in Taipei area during the period of 2005 to 2007. This study reveals a strong nonlinear C-R pattern that the PM2.5 increment can significantly affect respiratory health at PM2.5 concentration ≤ 18.17µg/m3 for both preschool children and schoolchildren. The elevated risks are especially present in the category of acute respiratory infections. PM2.5 increase is mostly non-significant to the more severe respiratory diseases, e.g., COPD and pneumonia, over the ranges of 8.85-92.45µg/m3. The significantly higher relative rate of respiratory clinic visit most likely concentrated at populated areas. We highlight the nonlinearity of the respiratory health impacts of PM2.5 on children's populations from the first study, to our knowledge, to investigate this population-based association. The strong nonlinearity can possibly cause the inconsistency of PM2.5 health impact assessments with linear assumptions.

Neighborhood deprivation is strongly associated with participation in a population-based health check.

PubMed

Bender, Anne Mette; Kawachi, Ichiro; Jørgensen, Torben; Pisinger, Charlotta

2015-01-01

We sought to examine whether neighborhood deprivation is associated with participation in a large population-based health check. Such analyses will help answer the question whether health checks, which are designed to meet the needs of residents in deprived neighborhoods, may increase participation and prove to be more effective in preventing disease. In Europe, no study has previously looked at the association between neighborhood deprivation and participation in a population-based health check. The study population comprised 12,768 persons invited for a health check including screening for ischemic heart disease and lifestyle counseling. The study population was randomly drawn from a population of 179,097 persons living in 73 neighborhoods in Denmark. Data on neighborhood deprivation (percentage with basic education, with low income and not in work) and individual socioeconomic position were retrieved from national administrative registers. Multilevel regression analyses with log links and binary distributions were conducted to obtain relative risks, intraclass correlation coefficients and proportional change in variance. Large differences between neighborhoods existed in both deprivation levels and neighborhood health check participation rate (mean 53%; range 35-84%). In multilevel analyses adjusted for age and sex, higher levels of all three indicators of neighborhood deprivation and a deprivation score were associated with lower participation in a dose-response fashion. Persons living in the most deprived neighborhoods had up to 37% decreased probability of participating compared to those living in the least deprived neighborhoods. Inclusion of individual socioeconomic position in the model attenuated the neighborhood deprivation coefficients, but all except for income deprivation remained statistically significant. Neighborhood deprivation was associated with participation in a population-based health check in a dose-response manner, in which increasing neighborhood deprivation was associated with decreasing participation. This suggests the need to develop preventive health checks tailored to deprived neighborhoods.

Habitat characterization of western hoolock gibbons Hoolock hoolock by examining home range microhabitat use.

PubMed

Akers, Alice A; Anwarul Islam, Md; Nijman, Vincent

2013-10-01

Conserving a species depends on an understanding of its habitat requirements. Primatologists often characterize the habitat requirements of primates using macroscale population-based approaches relying on correlations between habitat attributes and population abundances between sites with varying levels of disturbance. This approach only works for species spread between several populations. The populations of some primates do not fulfill these criteria, forcing researchers to rely on individual-based (microscale) rather than population-based approaches for habitat characterization. We examined the reliability of using micro-scale habitat characterizations by studying the microhabitat preferences of a group of wild western hoolock gibbons (Hoolock hoolock) in order to compare our results to the habitat preferences of western hoolock gibbons identified during a macroscale study of populations across Bangladesh. We used stepwise discriminant analysis to differentiate between the areas of low, medium, and high usage based on microhabitat characteristics (tree species availability, altitude, canopy connection, distance from forest edge, and levels of human disturbance). The gibbons used interior forest habitat with low food tree availability most frequently for sleeping and socializing, and used edge habitat containing high food tree availability for medium periods for feeding. These results indicate that the gibbons prefer interior forest but are frequently forced to visit the forest edge to feed. Therefore, the optimal habitat would be interior forest away from human disturbance with high sleeping-tree and feeding-tree availability. These habitat preferences are consistent with the habitat attributes of Bangladesh's largest remaining western hoolock gibbon populations, which live in areas containing low agricultural encroachment and high food-tree availability. Microhabitat use studies can be used to characterize the habitat requirements of a species, but should include multiple scales of analysis wherever possible.

Designing Home-Based Telemedicine Systems for the Geriatric Population: An Empirical Study.

PubMed

Narasimha, Shraddhaa; Agnisarman, Sruthy; Chalil Madathil, Kapil; Gramopadhye, Anand; McElligott, James T

2018-02-01

Background and Introduction: Telemedicine, the process of providing healthcare remotely using communication devices, has the potential to be useful for the geriatric population when specifically designed for this age group. This study explored the design of four video telemedicine systems currently available and outlined issues with these systems that impact usability among the geriatric population. Based on the results, design suggestions were developed to improve telemedicine systems for this population. Using a between-subjects experimental design, the study considered four telemedicine systems used in Medical University of South Carolina. The study was conducted at a local retirement home. The participant pool consisted of 40 adults, 60 years or older. The dependent measures used were the mean times for telemedicine session initiation and video session, mean number of errors, post-test satisfaction ratings, the NASA-Task Load Index (NASA-TLX) workload measures, and the IBM-Computer Systems Usability Questionnaire measures. Statistical significance was found among the telemedicine systems' initiation times. The analysis of the qualitative data revealed several issues, including lengthy e-mail content, icon placement, and chat box design, which affect the usability of these systems for the geriatric population. Human factor-based design modifications, including short, precise e-mail content, appropriately placed icons, and the inclusion of instructions, are recommended to address the issues found in the qualitative study.

Methodology of a population-based stroke and TIA incidence and outcomes study: the Auckland Regional Community Stroke Study (ARCOS IV) 2011-2012.

PubMed

Krishnamurthi, Rita; Jones, Amy; Barber, P Alan; Barker-Collo, Suzanne; McPherson, Kathryn; Bennett, Derrick; Rush, Elaine; Suh, Flora; Starkey, Nicola; Theadom, Alice; Parag, Varsha; Rathnasabapathy, Yogini; Feigin, Valery L

2014-01-01

Stroke is a leading cause of death and disability worldwide. Stroke burden is immense as it leads to premature deaths, leaves survivors with ongoing disabilities, and has a major financial impact on the individual, their families, and the community. Reliable, high-quality evidence is needed on stroke risk factors, incidence, and outcomes to provide information on how best to reduce this burden. Population-based studies are regarded as the 'gold-standard' of measuring disease burden but are not common due to the logistical and financial challenges they present. The Auckland Regional Community Stroke Studies are among a few in the world that have been carried out at a population level and at regular intervals. The aim of the fourth Auckland Regional Community Stroke Studies IV is to examine the current measures of stroke incidence, prevalence, and outcomes as well the trends over four decades. This article describes the methodology of the Auckland Regional Community Stroke Studies IV with stroke and transient ischemic attacks cases registered over a 12-month period from March 1, 2011 to February 29, 2012. The methodology described may be used as a guide in order to design similar population-based stroke incidence and outcome studies in other countries and populations, thus facilitating the collection of most consistent and accurate stroke epidemiological data. © 2013 The Authors. International Journal of Stroke © 2013 World Stroke Organization.

Underreporting in alcohol surveys: whose drinking is underestimated?

PubMed

Livingston, Michael; Callinan, Sarah

2015-01-01

Population surveys typically produce underestimates of alcohol consumption of approximately 40%-50%. Researchers often undertake a uniform adjustment of survey data to weight estimates such that they match measures of consumption based on sales or tax data. This study explored whether there are differential rates of underestimation in self-reported consumption data by comparing data from two major population surveys in Australia. The study compared survey estimates of consumption for population subgroups from the National Drug Strategy Household Survey (NDSHS, using graduated-frequency questions, coverage = 55%) and the Australian arm of the International Alcohol Control Study (IAC, using within-location beverage-specific questions, coverage = 86%). Analyses examined age- and sex-based subgroups as well as subgroups based on rates of heavy episodic drinking. The graduated-frequency questions (NDSHS) underestimated consumption by 33% compared with the beverage-specific within-location questions (IAC). Underestimates were more marked for young males (40%) and middle-aged females (49%) and less marked for young females (15%) and older females (NDSHS estimates were 19% higher than IAC). Respondents who engaged infrequently or not at all in heavy episodic drinking underestimated their consumption by more (proportionally) than those who did (43% vs. 22%). Underreporting of alcohol consumption in population surveys using standard graduated-frequency questions is not uniform across either demographic or consumption-based subgroups of the population. More robust approaches to adjusting survey data to match objective measures of consumption are required.

Genetic polymorphisms of nine X-STR loci in four population groups from Inner Mongolia, China.

PubMed

Hou, Qiao-Fang; Yu, Bin; Li, Sheng-Bin

2007-02-01

Nine short tandem repeat (STR) markers on the X chromosome (DXS101, DXS6789, DXS6799, DXS6804, DXS7132, DXS7133, DXS7423, DXS8378, and HPRTB) were analyzed in four population groups (Mongol, Ewenki, Oroqen, and Daur) from Inner Mongolia, China, in order to learn about the genetic diversity, forensic suitability, and possible genetic affinities of the populations. Frequency estimates, Hardy-Weinberg equilibrium, and other parameters of forensic interest were computed. The results revealed that the nine markers have a moderate degree of variability in the population groups. Most heterozygosity values for the nine loci range from 0.480 to 0.891, and there are evident differences of genetic variability among the populations. A UPGMA tree constructed on the basis of the generated data shows very low genetic distance between Mongol and Han (Xi'an) populations. Our results based on genetic distance analysis are consistent with the results of earlier studies based on linguistics and the immigration history and origin of these populations. The minisatellite loci on the X chromosome studied here are not only useful in showing significant genetic variation between the populations, but also are suitable for human identity testing among Inner Mongolian populations.

The use of customised versus population-based birthweight standards in predicting perinatal mortality.

PubMed

Zhang, X; Platt, R W; Cnattingius, S; Joseph, K S; Kramer, M S

2007-04-01

The objective of this study was to critically examine potential artifacts and biases underlying the use of 'customised' standards of birthweight for gestational age (GA). Population-based cohort study. Sweden. A total of 782,303 singletons > or =28 weeks of gestation born in 1992-2001 to Nordic mothers with complete data on birthweight; GA; and maternal age, parity, height, and pre-pregnancy weight. We compared perinatal mortality in four groups of infants based on the following classification of small for gestational age (SGA): non-SGA based on either population-based or customised standards (the reference group), SGA based on the population-based standard only, SGA based on the customised standard only, and SGA according to both standards. We used graphical methods to compare GA-specific birthweight cutoffs for SGA using the two standards and also used logistic regression to control for differences in GA and maternal pre-pregnancy body mass index (BMI) in the four groups. Perinatal mortality, including stillbirth and neonatal death. Customisation led to a large artifactual increase in the proportion of SGA infants born preterm. Adjustment for differences in GA and maternal BMI markedly reduced the excess risk among infants classified as SGA by customised standards only. The large increase in perinatal mortality risk among infants classified as SGA based on customised standards is largely an artifact due to inclusion of more preterm births.

DEMOGRAPHIC CHARACTERISTICS OF THE NHEXAS-ARIZONA BORDER STUDY POPULATION

EPA Science Inventory

The NHEXAS-Arizona Border Study employed a population based probability design to recruit a representative cohort residing within 40 Km of the US-Mexico Border in Arizona. As an extension of the NHEXAS Arizona statewide survey, the border study was designed to determine the dis...

Estimating Kinship in Admixed Populations

PubMed Central

Thornton, Timothy; Tang, Hua; Hoffmann, Thomas J.; Ochs-Balcom, Heather M.; Caan, Bette J.; Risch, Neil

2012-01-01

Genome-wide association studies (GWASs) are commonly used for the mapping of genetic loci that influence complex traits. A problem that is often encountered in both population-based and family-based GWASs is that of identifying cryptic relatedness and population stratification because it is well known that failure to appropriately account for both pedigree and population structure can lead to spurious association. A number of methods have been proposed for identifying relatives in samples from homogeneous populations. A strong assumption of population homogeneity, however, is often untenable, and many GWASs include samples from structured populations. Here, we consider the problem of estimating relatedness in structured populations with admixed ancestry. We propose a method, REAP (relatedness estimation in admixed populations), for robust estimation of identity by descent (IBD)-sharing probabilities and kinship coefficients in admixed populations. REAP appropriately accounts for population structure and ancestry-related assortative mating by using individual-specific allele frequencies at SNPs that are calculated on the basis of ancestry derived from whole-genome analysis. In simulation studies with related individuals and admixture from highly divergent populations, we demonstrate that REAP gives accurate IBD-sharing probabilities and kinship coefficients. We apply REAP to the Mexican Americans in Los Angeles, California (MXL) population sample of release 3 of phase III of the International Haplotype Map Project; in this sample, we identify third- and fourth-degree relatives who have not previously been reported. We also apply REAP to the African American and Hispanic samples from the Women's Health Initiative SNP Health Association Resource (WHI-SHARe) study, in which hundreds of pairs of cryptically related individuals have been identified. PMID:22748210

A new method for studying population genetics of cyst nematodes based on Pool-Seq and genomewide allele frequency analysis.

PubMed

Mimee, Benjamin; Duceppe, Marc-Olivier; Véronneau, Pierre-Yves; Lafond-Lapalme, Joël; Jean, Martine; Belzile, François; Bélair, Guy

2015-11-01

Cyst nematodes are important agricultural pests responsible for billions of dollars of losses each year. Plant resistance is the most effective management tool, but it requires a close monitoring of population genetics. Current technologies for pathotyping and genotyping cyst nematodes are time-consuming, expensive and imprecise. In this study, we capitalized on the reproduction mode of cyst nematodes to develop a simple population genetic analysis pipeline based on genotyping-by-sequencing and Pool-Seq. This method yielded thousands of SNPs and allowed us to study the relationships between populations of different origins or pathotypes. Validation of the method on well-characterized populations also demonstrated that it was a powerful and accurate tool for population genetics. The genomewide allele frequencies of 23 populations of golden nematode, from nine countries and representing the five known pathotypes, were compared. A clear separation of the pathotypes and fine genetic relationships between and among global populations were obtained using this method. In addition to being powerful, this tool has proven to be very time- and cost-efficient and could be applied to other cyst nematode species. © 2015 Her Majesty the Queen in Right of Canada Molecular Ecology Resources © 2015 John Wiley & Sons Ltd Reproduced with the permission of the Minister of Agriculture and Agri-food.

First experiences in the implementation of biometric technology to link data from Health and Demographic Surveillance Systems with health facility data.

PubMed

Serwaa-Bonsu, Adwoa; Herbst, Abraham J; Reniers, Georges; Ijaa, Wilfred; Clark, Benjamin; Kabudula, Chodziwadziwa; Sankoh, Osman

2010-02-24

In developing countries, Health and Demographic Surveillance Systems (HDSSs) provide a framework for tracking demographic and health dynamics over time in a defined geographical area. Many HDSSs co-exist with facility-based data sources in the form of Health Management Information Systems (HMIS). Integrating both data sources through reliable record linkage could provide both numerator and denominator populations to estimate disease prevalence and incidence rates in the population and enable determination of accurate health service coverage. To measure the acceptability and performance of fingerprint biometrics to identify individuals in demographic surveillance populations and those attending health care facilities serving the surveillance populations. Two HDSS sites used fingerprint biometrics for patient and/or surveillance population participant identification. The proportion of individuals for whom a fingerprint could be successfully enrolled were characterised in terms of age and sex. Adult (18-65 years) fingerprint enrolment rates varied between 94.1% (95% CI 93.6-94.5) for facility-based fingerprint data collection at the Africa Centre site to 96.7% (95% CI 95.9-97.6) for population-based fingerprint data collection at the Agincourt site. Fingerprint enrolment rates in children under 1 year old (Africa Centre site) were only 55.1% (95% CI 52.7-57.4). By age 5, child fingerprint enrolment rates were comparable to those of adults. This work demonstrates the feasibility of fingerprint-based individual identification for population-based research in developing countries. Record linkage between demographic surveillance population databases and health care facility data based on biometric identification systems would allow for a more comprehensive evaluation of population health, including the ability to study health service utilisation from a population perspective, rather than the more restrictive health service perspective.

Polymorphic butterfly reveals the missing link in ecological speciation.

PubMed

Chamberlain, Nicola L; Hill, Ryan I; Kapan, Durrell D; Gilbert, Lawrence E; Kronforst, Marcus R

2009-11-06

Ecological speciation occurs when ecologically based, divergent selection causes the evolution of reproductive isolation. There are many empirical examples of this process; however, there exists a poorly characterized stage during which the traits that distinguish species ecologically and reproductively segregate in a single population. By using a combination of genetic mapping, mate-choice experiments, field observations, and population genetics, we studied a butterfly population with a mimetic wing color polymorphism and found that the butterflies exhibited partial, color-based, assortative mate preference. These traits represent the divergent, ecologically based signal and preference components of sexual isolation that usually distinguish incipient and sibling species. The association between behavior and recognition trait in a single population may enhance the probability of speciation and provides an example of the missing link between an interbreeding population and isolated species.

A SNP genetic linkage map based on the ‘Hamilton’ by ‘Spencer’ recombinant inbred line (RIL) population identified QTL for seed Isoflavone contents in soybean

USDA-ARS?s Scientific Manuscript database

Soybean is one of the most important crops worldwide for its protein, oil as well as the health beneficial phytoestrogens or isoflavone. This study reports a relatively dense SNP-Based genetic map based on ‘Hamilton’ by ‘Spencer’ recombinant inbred line (RIL) population and quantitative t...

Differences in Mental Health for Sexual Minority Students at Faith-Based Colleges/Universities and in the General College/University Population

ERIC Educational Resources Information Center

Cunningham, Jamal R.

2017-01-01

The present study is an examination of mental health between lesbian, gay, bisexual, queer, and questioning students at faith based colleges/universities (FBCU) and the general college/university population (GCUP), which includes mostly non-faith based colleges/universities (NFBCU) as well as some FBCU. Current literature on this topic is sparse.…

Gender differences in the management of acute coronary syndrome patients: One year results from HPIAR (HP-India ACS Registry).

PubMed

Mahajan, Kunal; Negi, Prakash Chand; Merwaha, Rajeev; Mahajan, Nitin; Chauhan, Vivek; Asotra, Sanjeev

2017-12-01

Data from high-income countries suggest that women receive less intensive diagnostic and therapeutic management than men for acute coronary syndrome (ACS). There is a paucity of such data in the Indian population, which is 69% rural and prior studies focused mostly on urban populations. The objective of the present study was to identify the gender based differences in ACS management, if any, in a predominantly rural population. Data from 35 hospitals across Himachal Pradesh covering >90% of state population were collected for one year (July 2015-June 2016). A total of 2118 ACS subjects met inclusion criteria and baseline characteristics, in-hospital treatments and mortality rates were analyzed. Women constituted less than one-third of ACS population. Women were older compared to men and were more likely to present with NSTEMI/UA. Misinterpretation of initial symptoms and late presentation were also common in women. Fewer women received optimal guideline based treatment and PCI (0.9% vs 4.2%, p<0.01). Compare to men, women more often had Killip class >1 (27.3% vs 20.4%, p<0.01) and higher in-hospital mortality (8.5% vs 5.6%, p=0.009). On multivariate analysis the association between female gender and mortality was attenuated (adjusted odds ratio [OR]=1.36 [0.77-2.38]). The present study from India, is the first of its kind to evaluate the gender based differences among ACS patients, in a predominantly rural population. Our analysis demonstrates a significant gender based difference between symptom awareness and delay in presentation, management and in-hospital outcome. Further studies are warranted across other parts of country to investigate this gender disparity. Copyright © 2017 Elsevier B.V. All rights reserved.

Prevalence of cam hip shape morphology: a systematic review.

PubMed

Dickenson, E; Wall, P D H; Robinson, B; Fernandez, M; Parsons, H; Buchbinder, R; Griffin, D R

2016-06-01

Cam hip shape morphology is a recognised cause of femoroacetabular impingement (FAI) and is associated with hip osteoarthritis. Our aim was to systematically review the available epidemiological evidence assessing the prevalence of cam hip shape morphology in the general population and any studied subgroups including subjects with and without hip pain. All studies that reported the prevalence of cam morphology, measured by alpha angles, in subjects aged 18 and over, irrespective of study population or presence of hip symptoms were considered for inclusion. We searched AMED, MEDLINE, EMBASE, CINAHL and CENTRAL in October 2015. Two authors independently identified eligible studies and assessed risk of bias. We planned to pool data of studies considered clinically homogenous. Thirty studies met inclusion criteria. None of the included studies were truly population-based: three included non-representative subgroups of the general population, 19 included differing clinical populations, while eight included professional athletes. All studies were judged to be at high risk of bias. Due to substantial clinical heterogeneity meta analysis was not possible. Across all studies, the prevalence estimates of cam morphology ranged from 5 to 75% of participants affected. We were unable to demonstrate a higher prevalence in selected subgroups such as athletes or those with hip pain. There is currently insufficient high quality data to determine the true prevalence of cam morphology in the general population or selected subgroups. Well-designed population-based epidemiological studies that use homogenous case definitions are required to determine the prevalence of cam morphology and its relationship to hip pain. Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Evidence for Association of the E23K Variant of KCNJ11 Gene with Type 2 Diabetes in Tunisian Population: Population-Based Study and Meta-Analysis

PubMed Central

Lasram, Khaled; Ben Halim, Nizar; Hsouna, Sana; Kefi, Rym; Arfa, Imen; Ghazouani, Welid; Jamoussi, Henda; Benrahma, Houda; Kharrat, Najla; Rebai, Ahmed; Ben Ammar, Slim; Bahri, Sonia; Barakat, Abdelhamid; Abid, Abdelmajid; Abdelhak, Sonia

2014-01-01

Aims. Genetic association studies have reported the E23K variant of KCNJ11 gene to be associated with Type 2 diabetes. In Arab populations, only four studies have investigated the role of this variant. We aimed to replicate and validate the association between the E23K variant and Type 2 diabetes in Tunisian and Arab populations. Methods. We have performed a case-control association study including 250 Tunisian patients with Type 2 diabetes and 267 controls. Allelic association has also been evaluated by 2 meta-analyses including all population-based studies among Tunisians and Arabs (2 and 5 populations, resp.). Results. A significant association between the E23K variant and Type 2 diabetes was found (OR = 1.6, 95% CI = 1.14–2.27, and P = 0.007). Furthermore, our meta-analysis has confirmed the significant role of the E23K variant in susceptibility of Type 2 diabetes in Tunisian and Arab populations (OR = 1.29, 95% CI = 1.15–1.46, and P < 10−3 and OR = 1.33, 95% CI = 1.13–1.56, and P = 0.001, resp.). Conclusion. Both case-control and meta-analyses results revealed the significant association between the E23K variant of KCNJ11 and Type 2 diabetes among Tunisians and Arabs. PMID:25165692

Population genetic testing for cancer susceptibility: founder mutations to genomes.

PubMed

Foulkes, William D; Knoppers, Bartha Maria; Turnbull, Clare

2016-01-01

The current standard model for identifying carriers of high-risk mutations in cancer-susceptibility genes (CSGs) generally involves a process that is not amenable to population-based testing: access to genetic tests is typically regulated by health-care providers on the basis of a labour-intensive assessment of an individual's personal and family history of cancer, with face-to-face genetic counselling performed before mutation testing. Several studies have shown that application of these selection criteria results in a substantial proportion of mutation carriers being missed. Population-based genetic testing has been proposed as an alternative approach to determining cancer susceptibility, and aims for a more-comprehensive detection of mutation carriers. Herein, we review the existing data on population-based genetic testing, and consider some of the barriers, pitfalls, and challenges related to the possible expansion of this approach. We consider mechanisms by which population-based genetic testing for cancer susceptibility could be delivered, and suggest how such genetic testing might be integrated into existing and emerging health-care structures. The existing models of genetic testing (including issues relating to informed consent) will very likely require considerable alteration if the potential benefits of population-based genetic testing are to be fully realized.

Chlamydia prevalence in the general population: is there a sex difference? a systematic review

PubMed Central

2013-01-01

Background The focus of Chlamydia trachomatis screening and testing lies more on women than on men. The study aim was to establish by systematic review the prevalence of urogenital Chlamydia trachomatis infection in men and women in the general population. Methods Electronic databases and reference lists were searched from 2000 to 2013 using the key words “Chlamydia trachomatis”, “population-based study” and “disease prevalence”. Reference lists were checked. Studies were included in the analysis if Chlamydia trachomatis prevalence was reported for both men and women in a population-based study. Prevalence rates for men and women were described as well as highest prevalence rate by age and sex. The difference in prevalence between the sexes in each study was calculated. Results Twenty-five studies met the inclusion criteria and quality assessment for the review. In nine of the twenty-five studies there was a statistically significant sex difference in the chlamydia prevalence. In all nine studies the prevalence of chlamydia was higher in women than in men. The prevalence for women varied from 1.1% to 10.6% and for men from 0.1% to 12.1%. The average chlamydia prevalence is highly variable between countries. The highest prevalence of chlamydia occurred predominantly in younger age groups (< 25 years). The absence of symptoms in population-based urogenital chlamydia infection is common in men and women (mean 88.5% versus 68.3%). Conclusions The urogenital chlamydia trachomatis prevalence in the general population is more similar than dissimilar for men and women. A modest sex difference is apparent. The prevalence rates can be used to inform chlamydia screening strategies in general practice. PMID:24215287

Childhood diet in relation to Sámi and Norwegian ethnicity in northern and mid-Norway--the SAMINOR study.

PubMed

Brustad, M; Parr, C L; Melhus, M; Lund, E

2008-02-01

The purpose of this work was to identify dietary patterns in the past using cluster analysis of reported diet in childhood, and to assess predictors for dietary patterns in relation to ethnicity in the population in the Sámi core areas in Norway. The Sámis are an indigenous population living in the border areas of Norway, Sweden, Finland and Russia. Population-based, cross-sectional study, using self-administered questionnaires. A food-frequency questionnaire covering selected food items eaten in childhood was used. The questionnaire also provided data on ethnicity. This study was based on data collected from 7614 subjects participating in The Population Based Study of Health and Living Conditions in Areas with a Mixed Sámi and Norwegian Population (the SAMINOR study) who grew up in the SAMINOR geographical areas, i.e. areas with mixed Sámi and Norwegian populations in Norway. Four dietary clusters were identified: a reindeer meat cluster; a cluster with high intakes of fish, traditional fish products and mutton, in addition to food sources from the local environment; a Westernised food cluster with high intakes of meat balls and sausages; and a cluster with a high intake of fish, but not any other foods in the questionnaire. The cluster distribution differed by ethnicity, but the effect of ethnicity on diet differed by coastal and inland residence. Our study has shown that data gathered through the limited questionnaire could be used to group the study sample into different dietary clusters, which we believe will be useful for further research on relationships between diet in childhood and health in the Sámi core areas in Norway.

[Assessing incident cardiovascular and metabolic diseases in epidemiological cohort studies in Germany].

PubMed

Herrmann, Wolfram J; Weikert, Cornelia; Bergmann, Manuela; Boeing, Heiner; Katzke, Verena A; Kaaks, Rudolf; Tiller, Daniel; Greiser, Karin Halina; Heier, Margit; Meisinger, Christa; Schmidt, Carsten Oliver; Neuhauser, Hannelore; Heidemann, Christin; Jünger, Claus; Wild, Philipp S; Schramm, Sara Helena; Jöckel, Karl-Heinz; Dörr, Marcus; Pischon, Tobias

2018-04-01

Cardiovascular and metabolic diseases are a major cause of mortality and loss of quality of life in Germany. Research into risk factors of these diseases requires large population-based cohort studies. Complete and accurate assessment of the incidence of cardiovascular and metabolic diseases is a key element for valid interpretation of the results from such studies. Our aim was to identify population-based cohort studies with incidence of cardiovascular and metabolic diseases in Germany and to summarize their methods for assessment and classification of disease endpoints, including myocardial infarction, type 2 diabetes, stroke, heart failure, and arterial hypertension. Within the framework of a workshop, representatives of the ascertained population-based cohort studies in Germany with incidence of cardiovascular or metabolic diseases were invited to present and to systematically provide information on their methods of endpoint identification. We identified eight studies from different regions in Germany with a total of 100,571 participants, aged 18-83 years at baseline. Self-reporting by study participants is the major source for further inquiries to assess disease endpoints in these studies. Most studies use additional data sources to verify the incidence of diseases, such as documents provided by the treating physician or hospital. Our results highlight the central role of self-reporting and the efforts associated with identification and verification of disease endpoints in cohort studies. They also provide a basis for future population-based studies that aim for standardized assessment of the incidence of cardiovascular and metabolic diseases.

Human mtDNA hypervariable regions, HVR I and II, hint at deep common maternal founder and subsequent maternal gene flow in Indian population groups.

PubMed

Sharma, Swarkar; Saha, Anjana; Rai, Ekta; Bhat, Audesh; Bamezai, Ramesh

2005-01-01

We have analysed the hypervariable regions (HVR I and II) of human mitochondrial DNA (mtDNA) in individuals from Uttar Pradesh (UP), Bihar (BI) and Punjab (PUNJ), belonging to the Indo-European linguistic group, and from South India (SI), that have their linguistic roots in Dravidian language. Our analysis revealed the presence of known and novel mutations in both hypervariable regions in the studied population groups. Median joining network analyses based on mtDNA showed extensive overlap in mtDNA lineages despite the extensive cultural and linguistic diversity. MDS plot analysis based on Fst distances suggested increased maternal genetic proximity for the studied population groups compared with other world populations. Mismatch distribution curves, respective neighbour joining trees and other statistical analyses showed that there were significant expansions. The study revealed an ancient common ancestry for the studied population groups, most probably through common founder female lineage(s), and also indicated that human migrations occurred (maybe across and within the Indian subcontinent) even after the initial phase of female migration to India.

Recruiting hard-to-reach United States population sub-groups via adaptations of snowball sampling strategy

PubMed Central

Sadler, Georgia Robins; Lee, Hau-Chen; Seung-Hwan Lim, Rod; Fullerton, Judith

2011-01-01

Nurse researchers and educators often engage in outreach to narrowly defined populations. This article offers examples of how variations on the snowball sampling recruitment strategy can be applied in the creation of culturally appropriate, community-based information dissemination efforts related to recruitment to health education programs and research studies. Examples from the primary author’s program of research are provided to demonstrate how adaptations of snowball sampling can be effectively used in the recruitment of members of traditionally underserved or vulnerable populations. The adaptation of snowball sampling techniques, as described in this article, helped the authors to gain access to each of the more vulnerable population groups of interest. The use of culturally sensitive recruitment strategies is both appropriate and effective in enlisting the involvement of members of vulnerable populations. Adaptations of snowball sampling strategies should be considered when recruiting participants for education programs or subjects for research studies when recruitment of a population based sample is not essential. PMID:20727089

Recruitment of hard-to-reach population subgroups via adaptations of the snowball sampling strategy.

PubMed

Sadler, Georgia Robins; Lee, Hau-Chen; Lim, Rod Seung-Hwan; Fullerton, Judith

2010-09-01

Nurse researchers and educators often engage in outreach to narrowly defined populations. This article offers examples of how variations on the snowball sampling recruitment strategy can be applied in the creation of culturally appropriate, community-based information dissemination efforts related to recruitment to health education programs and research studies. Examples from the primary author's program of research are provided to demonstrate how adaptations of snowball sampling can be used effectively in the recruitment of members of traditionally underserved or vulnerable populations. The adaptation of snowball sampling techniques, as described in this article, helped the authors to gain access to each of the more-vulnerable population groups of interest. The use of culturally sensitive recruitment strategies is both appropriate and effective in enlisting the involvement of members of vulnerable populations. Adaptations of snowball sampling strategies should be considered when recruiting participants for education programs or for research studies when the recruitment of a population-based sample is not essential.

Official statistics and claims data records indicate non-response and recall bias within survey-based estimates of health care utilization in the older population

PubMed Central

2013-01-01

Background The validity of survey-based health care utilization estimates in the older population has been poorly researched. Owing to data protection legislation and a great number of different health care insurance providers, the assessment of recall and non-response bias is challenging to impossible in many countries. The objective of our study was to compare estimates from a population-based study in older German adults with external secondary data. Methods We used data from the German KORA-Age study, which included 4,127 people aged 65–94 years. Self-report questions covered the utilization of long-term care services, inpatient services, outpatient services, and pharmaceuticals. We calculated age- and sex-standardized mean utilization rates in each domain and compared them with the corresponding estimates derived from official statistics and independent statutory health insurance data. Results The KORA-Age study underestimated the use of long-term care services (−52%), in-hospital days (−21%) and physician visits (−70%). In contrast, the assessment of drug consumption by postal self-report questionnaires yielded similar estimates to the analysis of insurance claims data (−9%). Conclusion Survey estimates based on self-report tend to underestimate true health care utilization in the older population. Direct validation studies are needed to disentangle the impact of recall and non-response bias. PMID:23286781

Genomic Approach to Understand the Association of DNA Repair with Longevity and Healthy Aging Using Genomic Databases of Oldest-Old Population

PubMed Central

Kim, Hyun Soo

2018-01-01

Aged population is increasing worldwide due to the aging process that is inevitable. Accordingly, longevity and healthy aging have been spotlighted to promote social contribution of aged population. Many studies in the past few decades have reported the process of aging and longevity, emphasizing the importance of maintaining genomic stability in exceptionally long-lived population. Underlying reason of longevity remains unclear due to its complexity involving multiple factors. With advances in sequencing technology and human genome-associated approaches, studies based on population-based genomic studies are increasing. In this review, we summarize recent longevity and healthy aging studies of human population focusing on DNA repair as a major factor in maintaining genome integrity. To keep pace with recent growth in genomic research, aging- and longevity-associated genomic databases are also briefly introduced. To suggest novel approaches to investigate longevity-associated genetic variants related to DNA repair using genomic databases, gene set analysis was conducted, focusing on DNA repair- and longevity-associated genes. Their biological networks were additionally analyzed to grasp major factors containing genetic variants of human longevity and healthy aging in DNA repair mechanisms. In summary, this review emphasizes DNA repair activity in human longevity and suggests approach to conduct DNA repair-associated genomic study on human healthy aging.

IDENTIFYING A POPULATION-BASED SAMPLE OF WOMEN OF REPRODUCTIVE AGE FOR ENVIRONMENTAL STUDIES USING A COMMERCIAL TELEPHONE DIRECTORY

EPA Science Inventory

Environmental studies examining reproductive endpoints such as spontaneous abortion or fertility often rely on very select study groups (i.e., convenience samples, highly exposed, etc.) that cannot be easily generalized to the overall population. For exposures limited to a parti...

Characteristics of and Implications for Students Participating in Alternate Assessments Based on Alternate Academic Achievement Standards

ERIC Educational Resources Information Center

Kearns, Jacqueline Farmer; Towles-Reeves, Elizabeth; Kleinert, Harold L.; Kleinert, Jane O'Regan; Thomas, Megan Kleine-Kracht

2011-01-01

Little research has precisely defined the population of students participating in alternate assessments based on alternate academic achievement standards (AA-AAAS). Therefore, the purpose of this article is twofold: (a) explicate the findings of a multistate study examining the characteristics of the population of students participating in…

Population delineation of polar bears using satellite collar data

USGS Publications Warehouse

Bethke, R.; Taylor, Mitchell K.; Amstrup, Steven C.; Messier, François

1996-01-01

To produce reliable estimates of the size or vital rates of a given population, it is important that the boundaries of the population under study are clearly defined. This is particularly critical for large, migratory animals where levels of sustainable harvest are based on these estimates, and where small errors may have serious long-term consequences for the population. Once populations are delineated, rates of exchange between adjacent populations can be determined and accounted/corrected for when calculating abundance (e.g., based on mark-recapture data). Using satellite radio-collar locations for polar bears in the western Canadian Arctic, we illustrate one approach to delineating wildlife populations that integrates cluster analysis methods for determining group membership with home range plotting procedures to define spatial utilization. This approach is flexible with respect to the specific procedures used and provides an objective and quantitative basis for defining population boundaries.

A population-based study on health and living conditions in areas with mixed Sami and Norwegian settlements - the SAMINOR 2 questionnaire study.

PubMed

Brustad, Magritt; Hansen, Ketil Lenert; Broderstad, Ann Ragnhild; Hansen, Solrunn; Melhus, Marita

2014-01-01

To describe the method, data collection procedure and participation in The Population-based Study on Health and Living Conditions in Areas with both Sami and Norwegian Settlements - the SAMINOR 2 questionnaire study. Cross-sectional and semi-longitudinal. In 2012, all inhabitants aged 18-69 and living in selected municipalities with both Sami and Norwegian settlements in Mid and Northern Norway were posted an invitation to participate in a questionnaire survey covering several topics related to health and living conditions. The geographical area was similar to the area where the SAMINOR 1 study was conducted in 2003/2004 with the exception of one additional municipality. Participants could alternatively use a web-based questionnaire with identical question and answer categories as the posted paper version. In total, 11,600 (27%) participated (16% used the web-based questionnaire), with a higher participation rate among those over 50 (37% for women and 32% for men). Some geographical variation in participation rates was found. In addition, for those invited who also participated in the SAMINOR 1 study, we found that the participation rates increased with the level of education and income, while there was little difference in participation rates across ethnic groups. The knowledge generated from future theme-specific research utilizing the SAMINOR 2 database has the potential to benefit the general population in this geographical area of Norway, and the Sami people in particular, by providing knowledge-based insight into the health and living conditions of the multi-ethnic population in these parts of Norway.

A comprehensive review of prehospital and in-hospital delay times in acute stroke care.

PubMed

Evenson, K R; Foraker, R E; Morris, D L; Rosamond, W D

2009-06-01

The purpose of this study was to systematically review and summarize prehospital and in-hospital stroke evaluation and treatment delay times. We identified 123 unique peer-reviewed studies published from 1981 to 2007 of prehospital and in-hospital delay time for evaluation and treatment of patients with stroke, transient ischemic attack, or stroke-like symptoms. Based on studies of 65 different population groups, the weighted Poisson regression indicated a 6.0% annual decline (P<0.001) in hours/year for prehospital delay, defined from symptom onset to emergency department arrival. For in-hospital delay, the weighted Poisson regression models indicated no meaningful changes in delay time from emergency department arrival to emergency department evaluation (3.1%, P=0.49 based on 12 population groups). There was a 10.2% annual decline in hours/year from emergency department arrival to neurology evaluation or notification (P=0.23 based on 16 population groups) and a 10.7% annual decline in hours/year for delay time from emergency department arrival to initiation of computed tomography (P=0.11 based on 23 population groups). Only one study reported on times from arrival to computed tomography scan interpretation, two studies on arrival to drug administration, and no studies on arrival to transfer to an in-patient setting, precluding generalizations. Prehospital delay continues to contribute the largest proportion of delay time. The next decade provides opportunities to establish more effective community-based interventions worldwide. It will be crucial to have effective stroke surveillance systems in place to better understand and improve both prehospital and in-hospital delays for acute stroke care.

The cost of vision loss in Canada. 1. Methodology.

PubMed

Gordon, Keith D; Cruess, Alan F; Bellan, Lorne; Mitchell, Scott; Pezzullo, M Lynne

2011-08-01

This paper outlines the methodology used to estimate the cost of vision loss in Canada. The results of this study will be presented in a second paper. The cost of vision loss (VL) in Canada was estimated using a prevalence-based approach. This was done by estimating the number of people with VL in a base period (2007) and the costs associated with treating them. The cost estimates included direct health system expenditures on eye conditions that cause VL, as well as other indirect financial costs such as productivity losses. Estimates were also made of the value of the loss of healthy life, measured in Disability Adjusted Life Years or DALY's. To estimate the number of cases of VL in the population, epidemiological data on prevalence rates were applied to population data. The number of cases of VL was stratified by gender, age, ethnicity, severity and cause. The following sources were used for estimating prevalence: Population-based eye studies; Canadian Surveys; Canadian journal articles and research studies; and International Population Based Eye Studies. Direct health costs were obtained primarily from Health Canada and Canadian Institute for Health Information (CIHI) sources, while costs associated with productivity losses were based on employment information compiled by Statistics Canada and on economic theory of productivity loss. Costs related to vision rehabilitation (VR) were obtained from Canadian VR organizations. This study shows that it is possible to estimate the costs for VL for a country in the absence of ongoing local epidemiological studies. Copyright © 2011 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

Prevalence of Candida bracarensis and Candida nivariensis in a Spanish collection of yeasts: comparison of results from a reference centre and from a population-based surveillance study of candidemia.

PubMed

Cuenca-Estrella, M; Gomez-Lopez, A; Isla, G; Rodriguez, D; Almirante, B; Pahissa, A; Rodriguez-Tudela, J L

2011-07-01

Two new species related to Candida glabrata, i.e., Candida nivariensis and Candida bracarensis, have been proposed. The occurrence of these species among isolates collected in a Spanish mycology reference laboratory in 2008-2009 was reviewed. In addition, strains recovered as part of an active population-based surveillance of candidemia conducted in Barcelona between 2002 and 2003 were also analyzed. Among 143 clinical isolates received in 2008-2009, three (2%) were identified as C. bracarensis and none as C. nivariensis through sequencing of their ribosomal DNA. Of the 31 strains initially identified as C. glabrata in the 2002-2003 population-based study (0.38 cases/100,000 population), none were found to belong to these related new species. Results from in vitro susceptibility studies of C. bracarensis isolates were comparable to those found with C. glabrata. Since new and cryptic species have been described, periodic surveillance including the use of molecular identification methods seems to be necessary in order to determine their frequency, geographical distribution and susceptibility profile.

Population size predicts technological complexity in Oceania

PubMed Central

Kline, Michelle A.; Boyd, Robert

2010-01-01

Much human adaptation depends on the gradual accumulation of culturally transmitted knowledge and technology. Recent models of this process predict that large, well-connected populations will have more diverse and complex tool kits than small, isolated populations. While several examples of the loss of technology in small populations are consistent with this prediction, it found no support in two systematic quantitative tests. Both studies were based on data from continental populations in which contact rates were not available, and therefore these studies do not provide a test of the models. Here, we show that in Oceania, around the time of early European contact, islands with small populations had less complicated marine foraging technology. This finding suggests that explanations of existing cultural variation based on optimality models alone are incomplete because demography plays an important role in generating cumulative cultural adaptation. It also indicates that hominin populations with similar cognitive abilities may leave very different archaeological records, a conclusion that has important implications for our understanding of the origin of anatomically modern humans and their evolved psychology. PMID:20392733

Stressful psychosocial factors and symptoms of gastroesophageal reflux disease: a population-based study in Norway.

PubMed

Jansson, Catarina; Wallander, Mari-Ann; Johansson, Saga; Johnsen, Roar; Hveem, Kristian

2010-01-01

Adverse psychosocial factors, including work-related stress, are, like gastroesophageal reflux disease (GERD), increasing health problems in industrialized countries. The importance of clarifying the relation between psychosocial factors and GERD has been stressed, but there are few population-based studies. This was a population-based, cross-sectional, case-control study based on two health surveys conducted in the Norwegian county Nord-Trondelag in 1984-86 and 1995-97. GERD symptoms were assessed in the second survey, which included 65,333 participants, representing 70% of the county's adult population. The 3153 persons reporting severe GERD symptoms were defined as cases and the 40,210 persons without such symptoms were defined as controls. Data on psychosocial factors and potential confounders were collected using questionnaires. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated using unconditional logistic regression. In models adjusted for age, sex, smoking, obesity and socioeconomic status, positive associations were observed between high job demands (OR 1.9, 95% CI 1.6-2.2), low job control (OR 1.1, 95% CI 1.0-1.2) and job strain (OR 1.9, 95% CI 1.6-2.4) and risk of GERD symptoms. Persons reporting low job satisfaction had a twofold (95% CI 1.6-2.5) increased risk of GERD compared to persons reporting high job satisfaction. Self pressure (OR 1.8, 95% CI 1.6-2.1) and time pressure (OR 2.0, 95% CI 1.7-2.4) were positively associated with GERD symptoms. These associations were attenuated after further adjustment for anxiety, depression, myocardial infarction, angina pectoris, stroke and insomnia, but remained statistically significant. This population-based study reveals a link between stressful psychosocial factors, including job strain, and GERD symptoms.

Dietary patterns and colorectal cancer: results from a Canadian population-based study.

PubMed

Chen, Zhi; Wang, Peizhong Peter; Woodrow, Jennifer; Zhu, Yun; Roebothan, Barbara; Mclaughlin, John R; Parfrey, Patrick S

2015-01-15

The relationship between major dietary patterns and colorectal cancer (CRC) in other populations largely remains consistent across studies. The objective of the present study is to assess if dietary patterns are associated with the risk of CRC in the population of Newfoundland and Labrador (NL). Data from a population based case-control study in the province of NL were analyzed, including 506 CRC patients (306 men and 200 women) and 673 controls (400 men and 273 women), aged 20-74 years. Dietary habits were assessed by a 169-item food frequency questionnaire (FFQ). Logistic regression analyses were performed to investigate the association between dietary patterns and the CRC risk. Three major dietary patterns were derived using factor analysis, namely a Meat-diet pattern, a Plant-based diet pattern and a Sugary-diet pattern. In combination the three dietary patterns explained 74% of the total variance in food intake. Results suggest that the Meat-diet and the Sugary-diet increased the risk of CRC with corresponding odds ratios (ORs) of 1.84 (95% CI: 1.19-2.86) and 2.26 (95% CI: 1.39-3.66) for people in the highest intake quintile compared to those in the lowest. Whereas plant-based diet pattern decreases the risk of CRC with a corresponding OR of 0.55 (95% CI: 0.35-0.87). Even though odds ratios (ORs) were not always statistically significant, largely similar associations across three cancer sites were found: the proximal colon, the distal colon, and the rectum. The finding that Meat-diet/Sugary-diet patterns increased and Plant-based diet pattern decreased the risk of CRC would guide the promotion of healthy eating for primary prevention of CRC in this population.

Prevalence of Diabetic Retinopathy in Urban Slums: The Aditya Jyot Diabetic Retinopathy in Urban Mumbai Slums Study-Report 2.

PubMed

Sunita, Mohan; Singh, Arvind Kumar; Rogye, Ashwini; Sonawane, Manish; Gaonkar, Ravina; Srinivasan, Radhika; Natarajan, Sundaram; Stevens, Fred C J; Scherpbier, A J J A; Kumaramanickavel, Govindasamy; McCarty, Catherine

2017-10-01

The aims of the study were to estimate the prevalence of diabetic retinopathy (DR) and enumerate history-based risk factors in the urban slums of Western India. The population-based study was conducted in seven wards of Mumbai urban slums, where we screened 6569 subjects of ≥ 40 years age, with a response rate of 98.4%, for type 2 diabetes mellitus (T2DM) based on American Diabetes Association criteria. All subjects with T2DM underwent dilated 30° seven-field stereo-fundus-photography for DR severity grading based on modified Airlie House classification. A multivariate logistic regression model was used to assess the correlation of DR with the history-based risk factors. The prevalence of DR in the general population of Mumbai urban slums was 1.41% (95% CI 0.59-2.23) and in the T2DM population it was 15.37% (95% CI 8.87-21.87). The positive associations with DR were the longer duration of DM (≥ 11 years: OR, 12.77; 95% CI 2.93-55.61) and male gender (OR, 2.05; 95% CI 1.08-3.89); increasing severity of retinopathy was also significantly associated with longer duration of DM (p < 0.001). However, history of hypertension, family history of DM, consanguineous marriage and migration status were not associated with DR in the study population. The prevalence of DR in the general population and T2DM subjects were 1.41% and 15.37% respectively in Mumbai urban slums. Duration of DM and male gender were significantly associated with DR. The slums in Western India show the trends of urban lifestyle influences similar to the rest of urban India.

Nonprobability and probability-based sampling strategies in sexual science.

PubMed

Catania, Joseph A; Dolcini, M Margaret; Orellana, Roberto; Narayanan, Vasudah

2015-01-01

With few exceptions, much of sexual science builds upon data from opportunistic nonprobability samples of limited generalizability. Although probability-based studies are considered the gold standard in terms of generalizability, they are costly to apply to many of the hard-to-reach populations of interest to sexologists. The present article discusses recent conclusions by sampling experts that have relevance to sexual science that advocates for nonprobability methods. In this regard, we provide an overview of Internet sampling as a useful, cost-efficient, nonprobability sampling method of value to sex researchers conducting modeling work or clinical trials. We also argue that probability-based sampling methods may be more readily applied in sex research with hard-to-reach populations than is typically thought. In this context, we provide three case studies that utilize qualitative and quantitative techniques directed at reducing limitations in applying probability-based sampling to hard-to-reach populations: indigenous Peruvians, African American youth, and urban men who have sex with men (MSM). Recommendations are made with regard to presampling studies, adaptive and disproportionate sampling methods, and strategies that may be utilized in evaluating nonprobability and probability-based sampling methods.

Considering the needs of English language learner populations: an examination of the population validity of reading intervention research.

PubMed

Moore, Brooke A; Klingner, Janette K

2014-01-01

This article synthesizes reading intervention research studies intended for use with struggling or at-risk students to determine which studies adequately address population validity, particularly in regard to the diverse reading needs of English language learners. An extensive search of the professional literature between 2001 and 2010 yielded a total of 67 reading intervention studies targeting at-risk elementary students. Findings revealed that many current research studies fail to adequately describe the sample, including the accessible and target populations, and to disaggregate their findings based on demographic characteristics. When population validity issues are not addressed, researchers cannot generalize findings to other populations of students, and it becomes unclear what intervention strategies work, especially with English language learner student populations. However, 25 studies did specifically recognize and address the needs of English language learners, indicating more researchers are taking into consideration the diverse needs of other struggling student populations. © Hammill Institute on Disabilities 2012.

Registry-based analysis of participator representativeness: a source of concern for sickness absence research?

PubMed

Knapstad, Marit; Löve, Jesper; Holmgren, Kristina; Hensing, Gunnel; Øverland, Simon

2016-10-21

Selective participation can bias results in epidemiological surveys. The importance of health status is often suggested as a possible explanation for non-participation but few empirical studies exist. In a population-based study, explicitly focused on sickness absence, health and work, we examined whether a history of high levels of sickness absence was associated with non-participation. The study is based on data from official sickness absence registers from participants, non-participants and the total target population of the baseline survey of the Health Assets Project (HAP). HAP is a population-based cohort study in the Västra Götaland region in South Western Sweden. HAP included a random population cohort (n=7984) and 2 cohorts with recent sickness absence (employees (n=6140) and non-employees (n=990)), extracted from the same overall general working-age population. We examined differences in participation rates between cohorts (2008), and differences in previous sickness absence (2001-2008) between participants (individual-level data) and non-participants or the target population (group-level data) within cohorts. Participants had statistically significant less registered sickness absence in the past than non-participants and the target population for some, but not all, of the years analysed. Yet these differences were not of substantial size. Other factors than sickness absence were more important in explaining differences in participation, whereby participants were more likely to be women, older, born in Nordic countries, married and have higher incomes than non-participants. Although specifically addressing sickness absence, having such experience did not add any substantial layer to selective participation in the present survey. Detailed measures are needed to gain a better understanding for health selection in health-related surveys such as those addressing sickness absence, for instance in order to discriminate between selection due to ability or motivation for participation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

A Nationwide Population-Based Approach to Study Health-Related and Psychosocial Aspects of Neurofibromatosis Type 1

DTIC Science & Technology

2015-07-01

Neurofibromatosis Type 1 PRINCIPAL INVESTIGATOR: Dr. Jeanette Falck Winther CONTRACTING ORGANIZATION: Danish Cancer Society Research Center Copenhagen, Denmark...Study Health-Related and Psychosocial Aspects of Neurofibromatosis Type 1 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...Clinics in Denmark and a clinical geneticist with expertise in ethical aspects. 15. SUBJECT TERMS Neurofibromatosis type 1, population-based, nation

[The Study of Health in Pomerania (SHIP) reference values for cardiopulmonary exercise testing].

PubMed

Gläser, S; Ittermann, T; Schäper, C; Obst, A; Dörr, M; Spielhagen, T; Felix, S B; Völzke, H; Bollmann, T; Opitz, C F; Warnke, C; Koch, B; Ewert, R

2013-01-01

The interpretation of gas exchange measured by cardiopulmonary exercise testing (CPET) depends on reliable reference values. Within the population based Study of Health in Pomerania (SHIP) CPET was assessed in 1706 volunteers. The assessment based on symptom limited exercise tests on a bicycle in a sitting position according to a modified Jones protocol. CPET was embedded in an extensive examination program. After the exclusion of active smokers and volunteers with evidence of cardiopulmonary and musculoskeletal disorders the reference population comprised 616 healthy subjects (333 women) aged 25 to 85 years. Reference equations including upper and/or lower limits based on quantile regression were assessed. All values were corrected for the most important influencing factors.This study provides reference equations for gas exchange and exercise capacity assessed within a population in Germany. © Georg Thieme Verlag KG Stuttgart · New York.

Comparison of self-report influenza vaccination coverage with data from a population based computerized vaccination registry and factors associated with discordance.

PubMed

Jiménez-García, Rodrigo; Hernandez-Barrera, Valentín; Rodríguez-Rieiro, Cristina; Carrasco Garrido, Pilar; López de Andres, Ana; Jimenez-Trujillo, Isabel; Esteban-Vasallo, María D; Domínguez-Berjón, Maria Felicitas; de Miguel-Diez, Javier; Astray-Mochales, Jenaro

2014-07-31

We aim to compare influenza vaccination coverages obtained using two different methods; a population based computerized vaccination registry and self-reported influenza vaccination status as captured by a population survey. The study was conducted in the Autonomous Community of Madrid (ACM), Spain, and refers to the 2011/12 influenza vaccination campaign. Information on influenza vaccination status according to a computerized registry was extracted from the SISPAL database and crossed with the electronic clinical records in primary care (ECRPC). Self-reported vaccine uptake was obtained from subjects living in the ACM included in the 2011-12 Spanish National Health Survey (SNHS). Independent study variables included: age, sex, immigrant status and the presence of high risk chronic conditions. Vaccination coverages were calculated according to study variables. Crude and adjusted prevalence ratios were computed to assess concordance. The study population included 5,245,238 adults living in the ACM in year 2011 with an individual ECRPC and 1449 adult living the ACM and interviewed in the SNHS from October 2011 to June 2012. The weighted vaccination coverage for the study population according to self-reported data was 19.77% and 15.04% from computerized registries resulting in a crude prevalence ratio (cPR) of 1.31 (95% CI 1.20-1.44) so self-reported data significantly overestimated 31% the registry coverage. Self-reported coverages are always higher than registry based coverages when the study population is stratified by the study variables. Self-reported overestimation was higher among men than women, younger age groups, immigrants and those without chronic conditions. Both methods provide the most concordant estimations for the target population of the influenza vaccine. Self-report influenza vaccination uptake overestimates vaccination registries coverages. The validity of self-report seems to be negatively affected by socio-demographic variables and the absence of chronic conditions. Possible strategies must be considered and implemented to improve both coverage estimation methods. Copyright © 2014 Elsevier Ltd. All rights reserved.

A microsatellite guided insight into the genetic status of adi, an isolated hunting-gathering tribe of northeast India.

PubMed

Krithika, S; Maji, Suvendu; Vasulu, T S

2008-07-02

Tibeto-Burman populations of India provide an insight into the peopling of India and aid in understanding their genetic relationship with populations of East, South and Southeast Asia. The study investigates the genetic status of one such Tibeto-Burman group, Adi of Arunachal Pradesh based on 15 autosomal microsatellite markers. Further the study examines, based on 9 common microsatellite loci, the genetic relationship of Adi with 16 other Tibeto-Burman speakers of India and 28 neighboring populations of East and Southeast Asia. Overall, the results support the recent formation of the Adi sub-tribes from a putative ancestral group and reveal that geographic contiguity is a major influencing factor of the genetic affinity among the Tibeto-Burman populations of India.

A Microsatellite Guided Insight into the Genetic Status of Adi, an Isolated Hunting-Gathering Tribe of Northeast India

PubMed Central

Krithika, S.; Maji, Suvendu; Vasulu, T. S.

2008-01-01

Tibeto-Burman populations of India provide an insight into the peopling of India and aid in understanding their genetic relationship with populations of East, South and Southeast Asia. The study investigates the genetic status of one such Tibeto-Burman group, Adi of Arunachal Pradesh based on 15 autosomal microsatellite markers. Further the study examines, based on 9 common microsatellite loci, the genetic relationship of Adi with 16 other Tibeto-Burman speakers of India and 28 neighboring populations of East and Southeast Asia. Overall, the results support the recent formation of the Adi sub-tribes from a putative ancestral group and reveal that geographic contiguity is a major influencing factor of the genetic affinity among the Tibeto-Burman populations of India. PMID:18596928

Paternal genetic affinity between Western Austronesians and Daic populations.

PubMed

Li, Hui; Wen, Bo; Chen, Shu-Juo; Su, Bing; Pramoonjago, Patcharin; Liu, Yangfan; Pan, Shangling; Qin, Zhendong; Liu, Wenhong; Cheng, Xu; Yang, Ningning; Li, Xin; Tran, Dinhbinh; Lu, Daru; Hsu, Mu-Tsu; Deka, Ranjan; Marzuki, Sangkot; Tan, Chia-Chen; Jin, Li

2008-05-15

Austronesian is a linguistic family spread in most areas of the Southeast Asia, the Pacific Ocean, and the Indian Ocean. Based on their linguistic similarity, this linguistic family included Malayo-Polynesians and Taiwan aborigines. The linguistic similarity also led to the controversial hypothesis that Taiwan is the homeland of all the Malayo-Polynesians, a hypothesis that has been debated by ethnologists, linguists, archaeologists, and geneticists. It is well accepted that the Eastern Austronesians (Micronesians and Polynesians) derived from the Western Austronesians (Island Southeast Asians and Taiwanese), and that the Daic populations on the mainland are supposed to be the headstream of all the Austronesian populations. In this report, we studied 20 SNPs and 7 STRs in the non-recombining region of the 1,509 Y chromosomes from 30 China Daic populations, 23 Indonesian and Vietnam Malayo-Polynesian populations, and 11 Taiwan aboriginal populations. These three groups show many resemblances in paternal lineages. Admixture analyses demonstrated that the Daic populations are hardly influenced by Han Chinese genetically, and that they make up the largest proportion of Indonesians. Most of the population samples contain a high frequency of haplogroup O1a-M119, which is nearly absent in other ethnic families. The STR network of haplogroup O1a* illustrated that Indonesian lineages did not derive from Taiwan aborigines as linguistic studies suggest, but from Daic populations. We show that, in contrast to the Taiwan homeland hypothesis, the Island Southeast Asians do not have a Taiwan origin based on their paternal lineages. Furthermore, we show that both Taiwan aborigines and Indonesians likely derived from the Daic populations based on their paternal lineages. These two populations seem to have evolved independently of each other. Our results indicate that a super-phylum, which includes Taiwan aborigines, Daic, and Malayo-Polynesians, is genetically educible.

Addressing Participant Validity in a Small Internet Health Survey (The Restore Study): Protocol and Recommendations for Survey Response Validation

PubMed Central

Dewitt, James; Capistrant, Benjamin; Kohli, Nidhi; Mitteldorf, Darryl; Merengwa, Enyinnaya; West, William

2018-01-01

Background While deduplication and cross-validation protocols have been recommended for large Web-based studies, protocols for survey response validation of smaller studies have not been published. Objective This paper reports the challenges of survey validation inherent in a small Web-based health survey research. Methods The subject population was North American, gay and bisexual, prostate cancer survivors, who represent an under-researched, hidden, difficult-to-recruit, minority-within-a-minority population. In 2015-2016, advertising on a large Web-based cancer survivor support network, using email and social media, yielded 478 completed surveys. Results Our manual deduplication and cross-validation protocol identified 289 survey submissions (289/478, 60.4%) as likely spam, most stemming from advertising on social media. The basic components of this deduplication and validation protocol are detailed. An unexpected challenge encountered was invalid survey responses evolving across the study period. This necessitated the static detection protocol be augmented with a dynamic one. Conclusions Five recommendations for validation of Web-based samples, especially with smaller difficult-to-recruit populations, are detailed. PMID:29691203

Physiologically Based Pharmacokinetic (PBPK) Modeling of Interstrain Variability in Trichloroethylene Metabolism in the Mouse

PubMed Central

Campbell, Jerry L.; Clewell, Harvey J.; Zhou, Yi-Hui; Wright, Fred A.; Guyton, Kathryn Z.

2014-01-01

Background: Quantitative estimation of toxicokinetic variability in the human population is a persistent challenge in risk assessment of environmental chemicals. Traditionally, interindividual differences in the population are accounted for by default assumptions or, in rare cases, are based on human toxicokinetic data. Objectives: We evaluated the utility of genetically diverse mouse strains for estimating toxicokinetic population variability for risk assessment, using trichloroethylene (TCE) metabolism as a case study. Methods: We used data on oxidative and glutathione conjugation metabolism of TCE in 16 inbred and 1 hybrid mouse strains to calibrate and extend existing physiologically based pharmacokinetic (PBPK) models. We added one-compartment models for glutathione metabolites and a two-compartment model for dichloroacetic acid (DCA). We used a Bayesian population analysis of interstrain variability to quantify variability in TCE metabolism. Results: Concentration–time profiles for TCE metabolism to oxidative and glutathione conjugation metabolites varied across strains. Median predictions for the metabolic flux through oxidation were less variable (5-fold range) than that through glutathione conjugation (10-fold range). For oxidative metabolites, median predictions of trichloroacetic acid production were less variable (2-fold range) than DCA production (5-fold range), although the uncertainty bounds for DCA exceeded the predicted variability. Conclusions: Population PBPK modeling of genetically diverse mouse strains can provide useful quantitative estimates of toxicokinetic population variability. When extrapolated to lower doses more relevant to environmental exposures, mouse population-derived variability estimates for TCE metabolism closely matched population variability estimates previously derived from human toxicokinetic studies with TCE, highlighting the utility of mouse interstrain metabolism studies for addressing toxicokinetic variability. Citation: Chiu WA, Campbell JL Jr, Clewell HJ III, Zhou YH, Wright FA, Guyton KZ, Rusyn I. 2014. Physiologically based pharmacokinetic (PBPK) modeling of interstrain variability in trichloroethylene metabolism in the mouse. Environ Health Perspect 122:456–463; http://dx.doi.org/10.1289/ehp.1307623 PMID:24518055

Mental health of survivors of 1984 Bhopal disaster: A continuing challenge

PubMed Central

Murthy, R. Srinivasa

2014-01-01

Bhopal disaster is an important milestone in Indian Industrial Psychiatry. The disaster was not only the biggest industrial disaster but also one in which complex forces have joined hands to demy the mental health needs of the population. Though the biggest general population epidemiological study over 5 years was carried out to understand the mental health impact of the disaster, the findings of this study did not get reflected in mental health care for the population. Furthermore, the needed longitudinal studies and evaluation of the interventions were not undertaken. There was no sharing of information with the survivors about the impact of the disaster on their health and well-being and sharing of skills for self-care. A result of these factors is the extreme degree of dissatisfaction in the population. Looking back, it would have met the needs of the Bhopal population, if the mental health services were community based and reaching the population, rather than the clinic-based approaches, there was a wide range of services, especially rehabilitation, continuous research into the changing mental health needs of the population and the effectiveness of interventions and most importantly, there was a continuous dialogue with the population and sharing of information with the general population. These are the tasks for the immediate future to reorganize the focus of mental health initiatives in Bhopal. Many lessons can be learnt from the Bhopal disaster and the continuing tragedy for the population. PMID:25788796

Child mental health differences amongst ethnic groups in Britain: a systematic review

PubMed Central

Goodman, Anna; Patel, Vikram; Leon, David A

2008-01-01

Background Inter-ethnic differences have been reported for many mental health outcomes in the UK, but no systematic review on child mental health has been published. The aim of this review is to compare the population-based prevalence of child mental disorders between ethnic groups in Britain, and relate these findings to ethnic differences in mental health service use. Methods A systematic search of bibliographic databases for population-based and clinic-based studies of children aged 0–19, including all ethnic groups and the main child mental disorders. We synthesised findings by comparing each minority group to the White British study sample. Results 31 population-based and 18 clinic-based studies met the inclusion criteria. Children in the main minority groups have similar or better mental health than White British children for common disorders, but may have higher rates for some less common conditions. The causes of these differences are unclear. There may be unmet need for services among Pakistani and Bangladeshi children. Conclusion Inter-ethnic differences exist but are largely unexplained. Future studies should address the challenges of cross-cultural psychiatry and investigate reasons for inter-ethnic differences. PMID:18655701

Comparison of Smoking, Drinking, and Marijuana Use between Students Present or Absent on the Day of a School-Based Survey

ERIC Educational Resources Information Center

Bovet, Pascal; Viswanathan, Bharathi; Faeh, David; Warren, Wick

2006-01-01

The aim of this population-based survey was to compare the prevalence of selected risk behaviors between students present or absent on the day of a school-based survey. The study population was a representative sample of all students of secondary schools in the Seychelles (Indian Ocean). Students absent on the day of the survey were traced and…

Bounce Back Now! Protocol of a population-based randomized controlled trial to examine the efficacy of a Web-based intervention with disaster-affected families.

PubMed

Ruggiero, Kenneth J; Davidson, Tatiana M; McCauley, Jenna; Gros, Kirstin Stauffacher; Welsh, Kyleen; Price, Matthew; Resnick, Heidi S; Danielson, Carla Kmett; Soltis, Kathryn; Galea, Sandro; Kilpatrick, Dean G; Saunders, Benjamin E; Nissenboim, Josh; Muzzy, Wendy; Fleeman, Anna; Amstadter, Ananda B

2015-01-01

Disasters have far-reaching and potentially long-lasting effects on youth and families. Research has consistently shown a clear increase in the prevalence of several mental health disorders after disasters, including depression and posttraumatic stress disorder. Widely accessible evidence-based interventions are needed to address this unmet need for youth and families, who are underrepresented in disaster research. Rapid growth in Internet and Smartphone access, as well as several Web based evaluation studies with various adult populations has shown that Web-based interventions are likely to be feasible in this context and can improve clinical outcomes. Such interventions also are generally cost-effective, can be targeted or personalized, and can easily be integrated in a stepped care approach to screening and intervention delivery. This is a protocol paper that describes an innovative study design in which we evaluate a self-help Web-based resource, Bounce Back Now, with a population-based sample of disaster affected adolescents and families. The paper includes description and justification for sampling selection and procedures, selection of assessment measures and methods, design of the intervention, and statistical evaluation of critical outcomes. Unique features of this study design include the use of address-based sampling to recruit a population-based sample of disaster-affected adolescents and parents, telephone and Web-based assessments, and development and evaluation of a highly individualized Web intervention for adolescents. Challenges related to large-scale evaluation of technology-delivered interventions with high-risk samples in time-sensitive research are discussed, as well as implications for future research and practice. Published by Elsevier Inc.

Bounce Back Now! Protocol of a Population-Based Randomized Controlled Trial to Examine the Efficacy of a Web-based Intervention with Disaster-Affected Families

PubMed Central

Ruggiero, Kenneth J.; Davidson, Tatiana M.; McCauley, Jenna; Gros, Kirstin Stauffacher; Welsh, Kyleen; Price, Matthew; Resnick, Heidi S.; Danielson, Carla Kmett; Soltis, Kathryn; Galea, Sandro; Kilpatrick, Dean G.; Saunders, Benjamin E.; Nissenboim, Josh; Muzzy, Wendy; Fleeman, Anna; Amstadter, Ananda B.

2014-01-01

Disasters have far-reaching and potentially long-lasting effects on youth and families. Research has consistently shown a clear increase in the prevalence of several mental health disorders after disasters, including depression and posttraumatic stress disorder. Widely accessible evidence-based interventions are needed to address this unmet need for youth and families, who are underrepresented in disaster research. Rapid growth in Internet and Smartphone access, as well as several web based evaluation studies with various adult populations has shown that web-based interventions are likely to be feasible in this context and can improve clinical outcomes. Such interventions also are generally cost-effective, can be targeted or personalized, and can easily be integrated in a stepped care approach to screening and intervention delivery. This is a protocol paper that describes an innovative study design in which we evaluate a self-help web-based resource, Bounce Back Now, with a population-based sample of disaster affected adolescents and families. The paper includes description and justification for sampling selection and procedures, selection of assessment measures and methods, design of the intervention, and statistical evaluation of critical outcomes. Unique features of this study design include the use of address-based sampling to recruit a population-based sample of disaster-affected adolescents and parents, telephone and web-based assessments, and development and evaluation of a highly individualized web intervention for adolescents. Challenges related to large-scale evaluation of technology-delivered interventions with high-risk samples in time-sensitive research are discussed, as well as implications for future research and practice. PMID:25478956

Population structure and genotypic variation of Crataegus pontica inferred by molecular markers.

PubMed

Rahmani, Mohammad-Shafie; Shabanian, Naghi; Khadivi-Khub, Abdollah; Woeste, Keith E; Badakhshan, Hedieh; Alikhani, Leila

2015-11-01

Information about the natural patterns of genetic variability and their evolutionary bases are of fundamental practical importance for sustainable forest management and conservation. In the present study, the genetic diversity of 164 individuals from fourteen natural populations of Crataegus pontica K.Koch was assessed for the first time using three genome-based molecular techniques; inter-retrotransposon amplified polymorphism (IRAP); inter-simple sequence repeats (ISSR) and start codon targeted (SCoT) polymorphism. IRAP, ISSR and SCoT analyses yielded 126, 254 and 199 scorable amplified bands, respectively, of which 90.48, 93.37 and 83.78% were polymorphic. ISSR revealed efficiency over IRAP and SCoT due to high effective multiplex ratio, marker index and resolving power. The dendrograms based on the markers used and combined data divided individuals into three major clusters. The correlation between the coefficient matrices for the IRAP, ISSR and SCoT data was significant. A higher level of genetic variation was observed within populations than among populations based on the markers used. The lower divergence levels depicted among the studied populations could be seen as evidence of gene flow. The promotion of gene exchange will be very beneficial to conserve and utilize the enormous genetic variability. Copyright © 2015 Elsevier B.V. All rights reserved.

A Place-Oriented, Mixed-Level Regionalization Method for Constructing Geographic Areas in Health Data Dissemination and Analysis

PubMed Central

Mu, Lan; Wang, Fahui; Chen, Vivien W.; Wu, Xiao-Cheng

2015-01-01

Similar geographic areas often have great variations in population size. In health data management and analysis, it is desirable to obtain regions of comparable population by decomposing areas of large population (to gain more spatial variability) and merging areas of small population (to mask privacy of data). Based on the Peano curve algorithm and modified scale-space clustering, this research proposes a mixed-level regionalization (MLR) method to construct geographic areas with comparable population. The method accounts for spatial connectivity and compactness, attributive homogeneity, and exogenous criteria such as minimum (and approximately equal) population or disease counts. A case study using Louisiana cancer data illustrates the MLR method and its strengths and limitations. A major benefit of the method is that most upper level geographic boundaries can be preserved to increase familiarity of constructed areas. Therefore, the MLR method is more human-oriented and place-based than computer-oriented and space-based. PMID:26251551

Uptake of atrial fibrillation screening aiming at stroke prevention: geo-mapping of target population and non-participation.

PubMed

Engdahl, Johan; Holmén, Anders; Rosenqvist, Mårten; Strömberg, Ulf

2013-08-03

In a screening study for silent atrial fibrillation (AF), which is a frequent source of cardiac emboli with ischemic stroke, the proportion of non-participants was considerable and their clinical profile differed from the participants' profile. We intended to geo-map the target population and non-participation in an attempt to understand factors related to screening uptake and, thereby, obtain useful information needed to intervene for improved uptake. In the municipality of Halmstad, Sweden, all residents born in 1934-1935 were invited to the screening study during April 2010 to February 2012. The total study group included 848 participants and 367 non-participants from 12 parishes. Geo-maps displaying participation, along with target-population-based geo-maps displaying proportion of immigrants and ischemic stroke incidence, were used. Smoothed non-participation ratios (SmNPR) varied from 0.81 to 1.24 across different parishes (SmNRP=1 corresponds to the expected participation based on the total study group). Among high risk individuals, the geographical variation was more pronounced (SmNPR range 0.75-1.51). Two parishes with higher share of immigrants and elevated population-based ischemic stroke incidence showed markedly lower participation, particularly among high-risk individuals. AF screening uptake varied evidently between parishes, particularly among high-risk individuals. Geo-mapping of target population and non-participation yielded useful information needed to intervene for improved screening uptake.

Seroprevalence of Helicobacter pylori in Hispanics living in Puerto Rico: A population-based study.

PubMed

González-Pons, María; Soto-Salgado, Marievelisse; Sevilla, Javier; Márquez-Lespier, Juan M; Morgan, Douglas; Pérez, Cynthia M; Cruz-Correa, Marcia

2018-02-01

Helicobacter pylori is an important etiologic factor for peptic ulcers and gastric cancer, one of the top ten leading causes of cancer death in Puerto Rico. However, the prevalence of H. pylori infections in this population was previously unknown. The aim of this study was to examine the seroprevalence of H. pylori and its associated risk factors in Puerto Rico. A cross-sectional study was designed using an existing population-based biorepository. Seropositivity was determined using the Premier ™ H. pylori immunoassay. Helicobacter pylori seroprevalence was estimated with 95% confidence using marginal standardization following logistic regression. To assess the risk factors associated with H. pylori seropositivity, a multivariable log-binomial model was fitted to estimate the prevalence ratio (PR) and its 95% confidence interval (95% CI). A total of 528 population-based serum samples were analyzed. The mean age of the study population was 41 ± 12 years, of whom 55.3% were females. The overall seroprevalence of H. pylori was 33.0% (95% CI = 28.3%-38.1%). Increasing age and having <12 years of education were significantly (P < .05) associated with H. pylori seropositivity in the multivariable model; however, residing in counties with low population density reached marginal significance (P = .085). We report that H. pylori infection is common among Hispanics living in Puerto Rico. The H. pylori seroprevalence observed in Puerto Rico is similar to the seroprevalence reported in the overall population of the United States. The association between H. pylori seroprevalence and the risk factors analyzed offers insight into the epidemiology of gastric cancer in Puerto Rico and warrants further investigation. © 2017 The Authors. Helicobacter Published by John Wiley & Sons Ltd.

Sun Exposure and Melanoma Survival: A GEM Study

PubMed Central

Berwick, Marianne; Reiner, Anne S.; Paine, Susan; Armstrong, Bruce K.; Kricker, Anne; Goumas, Chris; Cust, Anne E.; Thomas, Nancy E.; Groben, Pamela A.; From, Lynn; Busam, Klaus; Orlow, Irene; Marrett, Loraine D.; Gallagher, Richard P.; Gruber, Stephen B.; Anton-Culver, Hoda; Rosso, Stefano; Zanetti, Roberto; Kanetsky, Peter A.; Dwyer, Terry; Venn, Alison; Lee-Taylor, Julia; Begg, Colin B.

2014-01-01

Background We previously reported a significant association between higher ultraviolet radiation exposure before diagnosis and greater survival with melanoma in a population-based study in Connecticut. We sought to evaluate the hypothesis that sun exposure prior to diagnosis was associated with greater survival in a larger, international population-based study with more detailed exposure information. Methods We conducted a multi-center, international population-based study in four countries – Australia, Italy, Canada and the United States – with 3,578 cases of melanoma with an average of 7.4 years of follow-up. Measures of sun exposure included sunburn, intermittent exposure, hours of holiday sun exposure, hours of water-related outdoor activities, ambient UVB dose, histological solar elastosis and season of diagnosis. Results Results were not strongly supportive of the earlier hypothesis. Having had any sunburn in one year within 10 years of diagnosis was inversely associated with survival; solar elastosis – a measure of lifetime cumulative exposure – was not. Additionally, none of the intermittent exposure measures – water related activities and sunny holidays - were associated with melanoma-specific survival. Estimated ambient UVB dose was not associated with survival. Conclusion Although there was an apparent protective effect of sunburns within 10 years of diagnosis, there was only weak evidence in this large, international, population-based study of melanoma that sun exposure prior to diagnosis is associated with greater melanoma-specific survival. Impact This study adds to the evidence that sun exposure prior to melanoma diagnosis has little effect on survival with melanoma. PMID:25069694

Sun exposure and melanoma survival: a GEM study.

PubMed

Berwick, Marianne; Reiner, Anne S; Paine, Susan; Armstrong, Bruce K; Kricker, Anne; Goumas, Chris; Cust, Anne E; Thomas, Nancy E; Groben, Pamela A; From, Lynn; Busam, Klaus; Orlow, Irene; Marrett, Loraine D; Gallagher, Richard P; Gruber, Stephen B; Anton-Culver, Hoda; Rosso, Stefano; Zanetti, Roberto; Kanetsky, Peter A; Dwyer, Terry; Venn, Alison; Lee-Taylor, Julia; Begg, Colin B

2014-10-01

We previously reported a significant association between higher UV radiation exposure before diagnosis and greater survival with melanoma in a population-based study in Connecticut. We sought to evaluate the hypothesis that sun exposure before diagnosis was associated with greater survival in a larger, international population-based study with more detailed exposure information. We conducted a multicenter, international population-based study in four countries-Australia, Italy, Canada, and the United States-with 3,578 cases of melanoma with an average of 7.4 years of follow-up. Measures of sun exposure included sunburn, intermittent exposure, hours of holiday sun exposure, hours of water-related outdoor activities, ambient ultraviolet B (280-320 nm) dose, histologic solar elastosis, and season of diagnosis. Results were not strongly supportive of the earlier hypothesis. Having had any sunburn in 1 year within 10 years of diagnosis was inversely associated with survival; solar elastosis-a measure of lifetime cumulative exposure-was not. In addition, none of the intermittent exposure measures-water-related activities and sunny holidays-were associated with melanoma-specific survival. Estimated ambient UVB dose was not associated with survival. Although there was an apparent protective effect of sunburns within 10 years of diagnosis, there was only weak evidence in this large, international, population-based study of melanoma that sun exposure before diagnosis is associated with greater melanoma-specific survival. This study adds to the evidence that sun exposure before melanoma diagnosis has little effect on survival with melanoma. ©2014 American Association for Cancer Research.

Population-production-pollution nexus based air pollution management model for alleviating the atmospheric crisis in Beijing, China.

PubMed

Zeng, X T; Tong, Y F; Cui, L; Kong, X M; Sheng, Y N; Chen, L; Li, Y P

2017-07-15

In recent years, increscent emissions in the city of Beijing due to expanded population, accelerated industrialization and inter-regional pollutant transportation have led to hazardous atmospheric pollution issues. Although a number of anthropogenic control measures have been put into use, frequent/severe haze events have still challenged regional governments. In this study, a hybrid population-production-pollution nexus model (PPP) is proposed for air pollution management and air quality planning (AMP) with the aim to coordinate human activities and environmental protection. A fuzzy-stochastic mixed quadratic programming method (FSQ) is developed and introduced into a PPP for tackling atmospheric pollution issues with uncertainties. Based on the contribution of an index of population-production-pollution, a hybrid PPP-based AMP model that considers employment structure, industrial layout pattern, production mode, pollutant purification efficiency and a pollution mitigation scheme have been applied in Beijing. Results of the adjustment of employment structure, pollution mitigation scheme, and green gross domestic product under various environmental regulation scenarios are obtained and analyzed. This study can facilitate the identification of optimized policies for alleviating population-production-emission conflict in the study region, as well as ameliorating the hazardous air pollution crisis at an urban level. Copyright © 2017 Elsevier Ltd. All rights reserved.

Prevalence and Incidence of Systemic Lupus Erythematosus in a Population-Based Registry of American Indian and Alaska Native People, 2007–2009

PubMed Central

Ferucci, Elizabeth D.; Johnston, Janet M.; Gaddy, Jasmine R.; Sumner, Lisa; Posever, James O.; Choromanski, Tammy L.; Gordon, Caroline; Lim, S. Sam; Helmick, Charles G.

2015-01-01

Objective Few studies have investigated the epidemiology of systemic lupus erythematosus (SLE) in American Indian and Alaska Native populations. The objective of this study was to determine the prevalence and incidence of SLE in the Indian Health Service (IHS) active clinical population in 3 regions of the US. Methods For this population-based registry within the IHS, the denominator consisted of individuals in the IHS active clinical population in 2007, 2008, and/or 2009 and residing in a community in 1 of 3 specified regions. Potential SLE cases were identified based on the presence of a diagnostic code for SLE or related disorder in the IHS National Data Warehouse. Detailed medical record abstraction was performed for each potential case. The primary case definition was documentation in the medical record of ≥4 of the revised American College of Rheumatology criteria for the classification of SLE. Prevalence was calculated for 2007, and the mean annual incidence was calculated for the years 2007 through 2009. Results The age-adjusted prevalence and incidence of SLE according to the primary definition were 178 per 100,000 person-years (95% confidence interval [95% CI] 157–200) and 7.4 per 100,000 person-years (95% CI 5.1–10.4). Among women, the age-adjusted prevalence was 271, and the age-adjusted incidence was 10.4. The prevalence was highest in women ages 50–59 years and in the Phoenix Area IHS. Conclusion The first population-based lupus registry in the US American Indian and Alaska Native population has demonstrated that the prevalence and incidence of SLE are high. Our estimates are as high as or higher than the rates reported in the US black population. PMID:24891315

Estimating and modeling the cure fraction in population-based cancer survival analysis.

PubMed

Lambert, Paul C; Thompson, John R; Weston, Claire L; Dickman, Paul W

2007-07-01

In population-based cancer studies, cure is said to occur when the mortality (hazard) rate in the diseased group of individuals returns to the same level as that expected in the general population. The cure fraction (the proportion of patients cured of disease) is of interest to patients and is a useful measure to monitor trends in survival of curable disease. There are 2 main types of cure fraction model, the mixture cure fraction model and the non-mixture cure fraction model, with most previous work concentrating on the mixture cure fraction model. In this paper, we extend the parametric non-mixture cure fraction model to incorporate background mortality, thus providing estimates of the cure fraction in population-based cancer studies. We compare the estimates of relative survival and the cure fraction between the 2 types of model and also investigate the importance of modeling the ancillary parameters in the selected parametric distribution for both types of model.

[Hierarchical regionalization for spatial epidemiology: a case study of thyroid cancer incidence in Yiwu, Zhejiang].

PubMed

Teng, Shizhu; Jia, Qiaojuan; Huang, Yijian; Chen, Liangcao; Fei, Xufeng; Wu, Jiaping

2015-10-01

Sporadic cases occurring in mall geographic unit could lead to extreme value of incidence due to the small population bases, which would influence the analysis of actual incidence. This study introduced a method of hierarchy clustering and partitioning regionalization, which integrates areas with small population into larger areas with enough population by using Geographic Information System (GIS) based on the principles of spatial continuity and geographical similarity (homogeneity test). This method was applied in spatial epidemiology by using a data set of thyroid cancer incidence in Yiwu, Zhejiang province, between 2010 and 2013. Thyroid cancer incidence data were more reliable and stable in the new regionalized areas. Hotspot analysis (Getis-Ord) on the incidence in new areas indicated that there was obvious case clustering in the central area of Yiwu. This method can effectively solve the problem of small population base in small geographic units in spatial epidemiological analysis of thyroid cancer incidence and can be used for other diseases and in other areas.

Productivity losses in chronic obstructive pulmonary disease: a population-based survey.

PubMed

Erdal, Marta; Johannessen, Ane; Askildsen, Jan Erik; Eagan, Tomas; Gulsvik, Amund; Grønseth, Rune

2014-01-01

We aimed to estimate incremental productivity losses (sick leave and disability) of spirometry-defined chronic obstructive pulmonary disease (COPD) in a population-based sample and in hospital-recruited patients with COPD. Furthermore, we examined predictors of productivity losses by multivariate analyses. We performed four quarterly telephone interviews of 53 and 107 population-based patients with COPD and controls, as well as 102 hospital-recruited patients with COPD below retirement age. Information was gathered regarding annual productivity loss, exacerbations of respiratory symptoms and comorbidities. Incremental productivity losses were estimated by multivariate quantile median regression according to the human capital approach, adjusting for sex, age, smoking habits, education and lung function. Main effect variables were COPD/control status, number of comorbidities and exacerbations of respiratory symptoms. Altogether 55%, 87% and 31% of population-based COPD cases, controls and hospital patients, respectively, had a paid job at baseline. The annual incremental productivity losses were 5.8 (95% CI 1.4 to 10.1) and 330.6 (95% CI 327.8 to 333.3) days, comparing population-recruited and hospital-recruited patients with COPD to controls, respectively. There were significantly higher productivity losses associated with female sex and less education. Additional adjustments for comorbidities, exacerbations and FEV1% predicted explained all productivity losses in the population-based sample, as well as nearly 40% of the productivity losses in hospital-recruited patients. Annual incremental productivity losses were more than 50 times higher in hospital-recruited patients with COPD than that of population-recruited patients with COPD. To ensure a precise estimation of societal burden, studies on patients with COPD should be population-based.

International comparison of experience-based health state values at the population level.

PubMed

Heijink, Richard; Reitmeir, Peter; Leidl, Reiner

2017-07-07

Decision makers need to know whether health state values, an important component of summary measures of health, are valid for their target population. A key outcome is the individuals' valuation of their current health. This experience-based perspective is increasingly used to derive health state values. This study is the first to compare such experience-based valuations at the population level across countries. We examined the relationship between respondents' self-rated health as measured by the EQ-VAS, and the different dimensions and levels of the EQ-5D-3 L. The dataset included almost 32,000 survey respondents from 15 countries. We estimated generalized linear models with logit link function, including country-specific models and pooled-data models with country effects. The results showed significant and meaningful differences in the valuation of health states and individual health dimensions between countries, even though similarities were present too. Between countries, coefficients correlated positively for the values of mobility, self-care and usual activities, but not for the values of pain and anxiety, thus underlining structural differences. The findings indicate that, ideally, population-specific experience-based value sets are developed and used for the calculation of health outcomes. Otherwise, sensitivity analyses are needed. Furthermore, transferring the results of foreign studies into the national context should be performed with caution. We recommend future studies to investigate the causes of differences in experience-based health state values through a single international study possibly complemented with qualitative research on the determinants of valuation.

Unresolved versus resolved: testing the validity of young simple stellar population models with VLT/MUSE observations of NGC 3603

NASA Astrophysics Data System (ADS)

Kuncarayakti, H.; Galbany, L.; Anderson, J. P.; Krühler, T.; Hamuy, M.

2016-09-01

Context. Stellar populations are the building blocks of galaxies, including the Milky Way. The majority, if not all, extragalactic studies are entangled with the use of stellar population models given the unresolved nature of their observation. Extragalactic systems contain multiple stellar populations with complex star formation histories. However, studies of these systems are mainly based upon the principles of simple stellar populations (SSP). Hence, it is critical to examine the validity of SSP models. Aims: This work aims to empirically test the validity of SSP models. This is done by comparing SSP models against observations of spatially resolved young stellar population in the determination of its physical properties, that is, age and metallicity. Methods: Integral field spectroscopy of a young stellar cluster in the Milky Way, NGC 3603, was used to study the properties of the cluster as both a resolved and unresolved stellar population. The unresolved stellar population was analysed using the Hα equivalent width as an age indicator and the ratio of strong emission lines to infer metallicity. In addition, spectral energy distribution (SED) fitting using STARLIGHT was used to infer these properties from the integrated spectrum. Independently, the resolved stellar population was analysed using the colour-magnitude diagram (CMD) to determine age and metallicity. As the SSP model represents the unresolved stellar population, the derived age and metallicity were tested to determine whether they agree with those derived from resolved stars. Results: The age and metallicity estimate of NGC 3603 derived from integrated spectroscopy are confirmed to be within the range of those derived from the CMD of the resolved stellar population, including other estimates found in the literature. The result from this pilot study supports the reliability of SSP models for studying unresolved young stellar populations. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programme 60.A-9344.

Mapping the Risk of Snakebite in Sri Lanka - A National Survey with Geospatial Analysis.

PubMed

Ediriweera, Dileepa Senajith; Kasturiratne, Anuradhani; Pathmeswaran, Arunasalam; Gunawardena, Nipul Kithsiri; Wijayawickrama, Buddhika Asiri; Jayamanne, Shaluka Francis; Isbister, Geoffrey Kennedy; Dawson, Andrew; Giorgi, Emanuele; Diggle, Peter John; Lalloo, David Griffith; de Silva, Hithanadura Janaka

2016-07-01

There is a paucity of robust epidemiological data on snakebite, and data available from hospitals and localized or time-limited surveys have major limitations. No study has investigated the incidence of snakebite across a whole country. We undertook a community-based national survey and model based geostatistics to determine incidence, envenoming, mortality and geographical pattern of snakebite in Sri Lanka. The survey was designed to sample a population distributed equally among the nine provinces of the country. The number of data collection clusters was divided among districts in proportion to their population. Within districts clusters were randomly selected. Population based incidence of snakebite and significant envenoming were estimated. Model-based geostatistics was used to develop snakebite risk maps for Sri Lanka. 1118 of the total of 14022 GN divisions with a population of 165665 (0.8%of the country's population) were surveyed. The crude overall community incidence of snakebite, envenoming and mortality were 398 (95% CI: 356-441), 151 (130-173) and 2.3 (0.2-4.4) per 100000 population, respectively. Risk maps showed wide variation in incidence within the country, and snakebite hotspots and cold spots were determined by considering the probability of exceeding the national incidence. This study provides community based incidence rates of snakebite and envenoming for Sri Lanka. The within-country spatial variation of bites can inform healthcare decision making and highlights the limitations associated with estimates of incidence from hospital data or localized surveys. Our methods are replicable, and these models can be adapted to other geographic regions after re-estimating spatial covariance parameters for the particular region.

Sequencing-Based Analysis of the Bacterial and Fungal Composition of Kefir Grains and Milks from Multiple Sources

PubMed Central

Marsh, Alan J.; O’Sullivan, Orla; Hill, Colin; Ross, R. Paul; Cotter, Paul D.

2013-01-01

Kefir is a fermented milk-based beverage to which a number of health-promoting properties have been attributed. The microbes responsible for the fermentation of milk to produce kefir consist of a complex association of bacteria and yeasts, bound within a polysaccharide matrix, known as the kefir grain. The consistency of this microbial population, and that present in the resultant beverage, has been the subject of a number of previous, almost exclusively culture-based, studies which have indicated differences depending on geographical location and culture conditions. However, culture-based identification studies are limited by virtue of only detecting species with the ability to grow on the specific medium used and thus culture-independent, molecular-based techniques offer the potential for a more comprehensive analysis of such communities. Here we describe a detailed investigation of the microbial population, both bacterial and fungal, of kefir, using high-throughput sequencing to analyse 25 kefir milks and associated grains sourced from 8 geographically distinct regions. This is the first occasion that this technology has been employed to investigate the fungal component of these populations or to reveal the microbial composition of such an extensive number of kefir grains or milks. As a result several genera and species not previously identified in kefir were revealed. Our analysis shows that the bacterial populations in kefir are dominated by 2 phyla, the Firmicutes and the Proteobacteria. It was also established that the fungal populations of kefir were dominated by the genera Kazachstania, Kluyveromyces and Naumovozyma, but that a variable sub-dominant population also exists. PMID:23894461

Sequencing-based analysis of the bacterial and fungal composition of kefir grains and milks from multiple sources.

PubMed

Marsh, Alan J; O'Sullivan, Orla; Hill, Colin; Ross, R Paul; Cotter, Paul D

2013-01-01

Kefir is a fermented milk-based beverage to which a number of health-promoting properties have been attributed. The microbes responsible for the fermentation of milk to produce kefir consist of a complex association of bacteria and yeasts, bound within a polysaccharide matrix, known as the kefir grain. The consistency of this microbial population, and that present in the resultant beverage, has been the subject of a number of previous, almost exclusively culture-based, studies which have indicated differences depending on geographical location and culture conditions. However, culture-based identification studies are limited by virtue of only detecting species with the ability to grow on the specific medium used and thus culture-independent, molecular-based techniques offer the potential for a more comprehensive analysis of such communities. Here we describe a detailed investigation of the microbial population, both bacterial and fungal, of kefir, using high-throughput sequencing to analyse 25 kefir milks and associated grains sourced from 8 geographically distinct regions. This is the first occasion that this technology has been employed to investigate the fungal component of these populations or to reveal the microbial composition of such an extensive number of kefir grains or milks. As a result several genera and species not previously identified in kefir were revealed. Our analysis shows that the bacterial populations in kefir are dominated by 2 phyla, the Firmicutes and the Proteobacteria. It was also established that the fungal populations of kefir were dominated by the genera Kazachstania, Kluyveromyces and Naumovozyma, but that a variable sub-dominant population also exists.

Out-of-pocket costs for cancer survivors between 5 and 10 years from diagnosis: an Italian population-based study.

PubMed

Baili, Paolo; Di Salvo, Francesca; de Lorenzo, Francesco; Maietta, Francesco; Pinto, Carmine; Rizzotto, Vera; Vicentini, Massimo; Rossi, Paolo Giorgi; Tumino, Rosario; Rollo, Patrizia Concetta; Tagliabue, Giovanna; Contiero, Paolo; Candela, Pina; Scuderi, Tiziana; Iannelli, Elisabetta; Cascinu, Stefano; Aurora, Fulvio; Agresti, Roberto; Turco, Alberto; Sant, Milena; Meneghini, Elisabetta; Micheli, Andrea

2016-05-01

To illustrate the out-of-pocket (OOP) costs incurred by a population-based group of patients from 5 to 10 years since their cancer diagnosis in a country with a nationwide public health system. Interviews on OOP costs to a sample of 5-10 year prevalent cases randomly extracted from four population-based cancer registries (CRs), two in the north and two in the south of Italy. The patients' general practitioners (GPs) gave assurance about the patient's physical and psychological condition for the interview. A zero-inflated negative binomial model was used to analyze OOP cost determinants. Two hundred six cancer patients were interviewed (48 % of the original sample). On average, a patient in the north spent €69 monthly, against €244 in the south. The main differences are for transport, room, and board (TRB) to reach the hospital and/or the cancer specialist (north €0; south €119). Everywhere, OOP costs without TRB costs were higher for patients with a low quality of life. Despite the limited participation, our study sample's characteristics are similar to those of the Italian cancer prevalence population, allowing us to generalize the results. The higher OOP costs in the south may be due to the scarcity of oncologic structures, obliging patients to seek assistance far from their residence. Implications for cancer survivors Cancer survivors need descriptive studies to show realistic data about their status. Future Italian and European descriptive studies on cancer survivorship should be based on population CRs and involve GPs in order to approach the patient at best.

Population Structure With Localized Haplotype Clusters

PubMed Central

Browning, Sharon R.; Weir, Bruce S.

2010-01-01

We propose a multilocus version of FST and a measure of haplotype diversity using localized haplotype clusters. Specifically, we use haplotype clusters identified with BEAGLE, which is a program implementing a hidden Markov model for localized haplotype clustering and performing several functions including inference of haplotype phase. We apply this methodology to HapMap phase 3 data. With this haplotype-cluster approach, African populations have highest diversity and lowest divergence from the ancestral population, East Asian populations have lowest diversity and highest divergence, and other populations (European, Indian, and Mexican) have intermediate levels of diversity and divergence. These relationships accord with expectation based on other studies and accepted models of human history. In contrast, the population-specific FST estimates obtained directly from single-nucleotide polymorphisms (SNPs) do not reflect such expected relationships. We show that ascertainment bias of SNPs has less impact on the proposed haplotype-cluster-based FST than on the SNP-based version, which provides a potential explanation for these results. Thus, these new measures of FST and haplotype-cluster diversity provide an important new tool for population genetic analysis of high-density SNP data. PMID:20457877

Integrating Science, Mathematics, and Sociology in an Inquiry-Based Study of Changing Population Density.

ERIC Educational Resources Information Center

Schlenker, Richard M.; Schlenker, Karl R.

2000-01-01

Presents a five-activity sequence designed to help students understand the effects of population doubling. Activities consider the effects of population doubling on human interactions, drinking water supplies, and food supply. Students also develop graphs of data and write research papers. (WRM)

A first insight into population structure and linkage disequilibrium in the US peanut minicore collection

USDA-ARS?s Scientific Manuscript database

Knowledge of genetic diversity, population structure, and degree of linkage disequilibrium (LD) in target association mapping populations is of great importance and is a prerequisite for LD-based mapping. In the present study, 96 genotypes comprising 92 accessions of the US peanut minicore collectio...

A population-based study on health and living conditions in areas with mixed Sami and Norwegian settlements – the SAMINOR 2 questionnaire study

PubMed Central

Brustad, Magritt; Hansen, Ketil Lenert; Broderstad, Ann Ragnhild; Hansen, Solrunn; Melhus, Marita

2014-01-01

Objectives To describe the method, data collection procedure and participation in The Population-based Study on Health and Living Conditions in Areas with both Sami and Norwegian Settlements – the SAMINOR 2 questionnaire study. Study design Cross-sectional and semi-longitudinal. Methods In 2012, all inhabitants aged 18–69 and living in selected municipalities with both Sami and Norwegian settlements in Mid and Northern Norway were posted an invitation to participate in a questionnaire survey covering several topics related to health and living conditions. The geographical area was similar to the area where the SAMINOR 1 study was conducted in 2003/2004 with the exception of one additional municipality. Participants could alternatively use a web-based questionnaire with identical question and answer categories as the posted paper version. Results In total, 11,600 (27%) participated (16% used the web-based questionnaire), with a higher participation rate among those over 50 (37% for women and 32% for men). Some geographical variation in participation rates was found. In addition, for those invited who also participated in the SAMINOR 1 study, we found that the participation rates increased with the level of education and income, while there was little difference in participation rates across ethnic groups. Conclusion The knowledge generated from future theme-specific research utilizing the SAMINOR 2 database has the potential to benefit the general population in this geographical area of Norway, and the Sami people in particular, by providing knowledge-based insight into the health and living conditions of the multi-ethnic population in these parts of Norway. PMID:24971230

Nationwide population-based study of cause-specific death rates in patients with psoriasis.

PubMed

Salahadeen, E; Torp-Pedersen, C; Gislason, G; Hansen, P R; Ahlehoff, O

2015-05-01

Psoriasis is a common chronic disease, mediated by type 1 and 17 helper T cell-driven inflammation. Epidemiological studies have demonstrated a wide range of comorbidities and increased mortality rates. However, the current evidence on psoriasis-related mortality is limited and nationwide data have not been presented previously. In a nationwide population-based cohort we evaluated all-cause and cause-specific death rates in patients with psoriasis as compared to the general population. The entire Danish population aged 18 and above, corresponding to a total of 5,458,627 individuals (50.7% female, 40.9 years ± 19.7), including 94,069 with mild psoriasis (53% female, 42.0 ± 17.0 years) and 28,253 with severe psoriasis (53.4% female, 43.0 ± 16.5 years), was included. A total of 884,661 deaths were recorded, including 10 916 in patients with mild psoriasis and 3699 in patients with severe psoriasis. The age at time of death varied by psoriasis status, i.e. 76.5 ± 14.0, 74.4 ± 12.8 and 72.0 ± 13.4 years, for the general population, mild psoriasis and severe psoriasis respectively. In general, the highest death rates were observed in patients with severe psoriasis. Overall death rates per 1000 patient years were 13.8 [confidence interval (CI) 13.8-13.8], 17.0 (CI 16.7-17.3) and 25.4 (CI 24.6-26.3) for the general population, patients with mild psoriasis and patients with severe psoriasis respectively. This nationwide population-based study of cause-specific death rates in patients with psoriasis demonstrated reduced lifespan and increased rates of all examined specific causes of death in patients with psoriasis compared to the general population. © 2014 European Academy of Dermatology and Venereology.

[Commentary on "group and organization: a dimension of collaboration of anthropology and epidemiology" by Song LM and Wang N].

PubMed

Liao, Su-Su; Zhang, Qing-Ning; Hou, Lei

2012-10-01

Epidemiology, as the study of occurrence and distribution of diseases or health events in specified populations and the application of the study to control health problems, is not just a method to study determinants of diseases at individual level through analysis of mass data based on individuals. To achieve the aims on the control of health problems in specified populations, Epidemiology should be public health-oriented to reduce incidence, prevalence and mortality, and should include study on determinants at the population level. Interdisplinarity and systems science will facilitate the breakthrough in improving health of the populations.

Mixed-Methods for Comparing Tobacco Cessation Interventions.

PubMed

Momin, Behnoosh; Neri, Antonio; Zhang, Lei; Kahende, Jennifer; Duke, Jennifer; Green, Sonya Goode; Malarcher, Ann; Stewart, Sherri L

2017-03-01

The National Comprehensive Cancer Control Program (NCCCP) and National Tobacco Control Program (NTCP) are both well-positioned to promote the use of population-based tobacco cessation interventions, such as state quitlines and Web-based interventions. This paper outlines the methodology used to conduct a comparative effectiveness research study of traditional and Web-based tobacco cessation and quitline promotion approaches. A mixed-methods study with three components was designed to address the effect of promotional activities on service usage and the comparative effectiveness of population-based smoking cessation activities across multiple states. The cessation intervention component followed 7,902 smokers (4,307 quitline users and 3,595 Web intervention users) to ascertain prevalence of 30-day abstinence rates 7 months after registering for smoking cessation services. User characteristics and quit success was compared across the two modalities. In the promotions component, reach and use of traditional and innovative promotion strategies were assessed for 24 states, including online advertising, state Web sites, social media, mobile applications, and their effects on quitline call volume. The partnership intervention component studied the extent of collaboration among six selected NCCCPs and NTCPs. This study will guide program staff and clinicians with evidence-based recommendations and best practices for implementation of tobacco cessation within their patient and community populations and establish an evidence base that can be used for decision making.

Exploring Population Admixture Dynamics via Empirical and Simulated Genome-wide Distribution of Ancestral Chromosomal Segments

PubMed Central

Jin, Wenfei; Wang, Sijia; Wang, Haifeng; Jin, Li; Xu, Shuhua

2012-01-01

The processes of genetic admixture determine the haplotype structure and linkage disequilibrium patterns of the admixed population, which is important for medical and evolutionary studies. However, most previous studies do not consider the inherent complexity of admixture processes. Here we proposed two approaches to explore population admixture dynamics, and we demonstrated, by analyzing genome-wide empirical and simulated data, that the approach based on the distribution of chromosomal segments of distinct ancestry (CSDAs) was more powerful than that based on the distribution of individual ancestry proportions. Analysis of 1,890 African Americans showed that a continuous gene flow model, in which the African American population continuously received gene flow from European populations over about 14 generations, best explained the admixture dynamics of African Americans among several putative models. Interestingly, we observed that some African Americans had much more European ancestry than the simulated samples, indicating substructures of local ancestries in African Americans that could have been caused by individuals from some particular lineages having repeatedly admixed with people of European ancestry. In contrast, the admixture dynamics of Mexicans could be explained by a gradual admixture model in which the Mexican population continuously received gene flow from both European and Amerindian populations over about 24 generations. Our results also indicated that recent gene flows from Sub-Saharan Africans have contributed to the gene pool of Middle Eastern populations such as Mozabite, Bedouin, and Palestinian. In summary, this study not only provides approaches to explore population admixture dynamics, but also advances our understanding on population history of African Americans, Mexicans, and Middle Eastern populations. PMID:23103229

The demand control model and circadian saliva cortisol variations in a Swedish population based sample (The PART study)

PubMed Central

Alderling, Magnus; Theorell, Töres; de la Torre, Bartolomé; Lundberg, Ingvar

2006-01-01

Background Previous studies of the relationship between job strain and blood or saliva cortisol levels have been small and based on selected occupational groups. Our aim was to examine the association between job strain and saliva cortisol levels in a population-based study in which a number of potential confounders could be adjusted for. Methods The material derives from a population-based study in Stockholm on mental health and its potential determinants. Two data collections were performed three years apart with more than 8500 subjects responding to a questionnaire in both waves. In this paper our analyses are based on 529 individuals who held a job, participated in both waves as well as in an interview linked to the second wave. They gave saliva samples at awakening, half an hour later, at lunchtime and before going to bed on a weekday in close connection with the interview. Job control and job demands were assessed from the questionnaire in the second wave. Mixed models were used to analyse the association between the demand control model and saliva cortisol. Results Women in low strain jobs (high control and low demands) had significantly lower cortisol levels half an hour after awakening than women in high strain (low control and high demands), active (high control and high demands) or passive jobs (low control and low demands). There were no significant differences between the groups during other parts of the day and furthermore there was no difference between the job strain, active and passive groups. For men, no differences were found between demand control groups. Conclusion This population-based study, on a relatively large sample, weakly support the hypothesis that the demand control model is associated with saliva cortisol concentrations. PMID:17129377

Changes in Black-legged Tick Population in New England with Future Climate Change

NASA Astrophysics Data System (ADS)

Krishnan, S.; Huber, M.

2015-12-01

Lyme disease is one of the most frequently reported vector-borne diseases in the United States. In the Northeastern United States, vector transmission is maintained in a horizontal transmission cycle between the vector, the black-legged ticks, and the vertebrate reservoir hosts, which include white-tailed deer, rodents and other medium to large sized mammals. Predicting how vector populations change with future climate change is critical to understanding disease spread in the future, and for developing suitable regional adaptation strategies. For the United States, these predictions have mostly been made using regressions based on field and lab studies, or using spatial suitability studies. However, the relation between tick populations at various life-cycle stages and climate variables are complex, necessitating a mechanistic approach. In this study, we present a framework for driving a mechanistic tick population model with high-resolution regional climate modeling projections. The goal is to estimate changes in black-legged tick populations in New England for the 21st century. The tick population model used is based on the mechanistic approach of Ogden et al., (2005) developed for Canada. Dynamically downscaled climate projections at a 3-kms resolution using the Weather and Research Forecasting Model (WRF) are used to drive the tick population model.

Imputation-Based Meta-Analysis of Severe Malaria in Three African Populations

PubMed Central

Band, Gavin; Le, Quang Si; Jostins, Luke; Pirinen, Matti; Kivinen, Katja; Jallow, Muminatou; Sisay-Joof, Fatoumatta; Bojang, Kalifa; Pinder, Margaret; Sirugo, Giorgio; Conway, David J.; Nyirongo, Vysaul; Kachala, David; Molyneux, Malcolm; Taylor, Terrie; Ndila, Carolyne; Peshu, Norbert; Marsh, Kevin; Williams, Thomas N.; Alcock, Daniel; Andrews, Robert; Edkins, Sarah; Gray, Emma; Hubbart, Christina; Jeffreys, Anna; Rowlands, Kate; Schuldt, Kathrin; Clark, Taane G.; Small, Kerrin S.; Teo, Yik Ying; Kwiatkowski, Dominic P.; Rockett, Kirk A.; Barrett, Jeffrey C.; Spencer, Chris C. A.

2013-01-01

Combining data from genome-wide association studies (GWAS) conducted at different locations, using genotype imputation and fixed-effects meta-analysis, has been a powerful approach for dissecting complex disease genetics in populations of European ancestry. Here we investigate the feasibility of applying the same approach in Africa, where genetic diversity, both within and between populations, is far more extensive. We analyse genome-wide data from approximately 5,000 individuals with severe malaria and 7,000 population controls from three different locations in Africa. Our results show that the standard approach is well powered to detect known malaria susceptibility loci when sample sizes are large, and that modern methods for association analysis can control the potential confounding effects of population structure. We show that pattern of association around the haemoglobin S allele differs substantially across populations due to differences in haplotype structure. Motivated by these observations we consider new approaches to association analysis that might prove valuable for multicentre GWAS in Africa: we relax the assumptions of SNP–based fixed effect analysis; we apply Bayesian approaches to allow for heterogeneity in the effect of an allele on risk across studies; and we introduce a region-based test to allow for heterogeneity in the location of causal alleles. PMID:23717212

Reader strategies: variability and error- methodology, findings, and health policy implications from a study of the U.S. population of mammographers

NASA Astrophysics Data System (ADS)

Beam, Craig A.

2002-04-01

Each year, approximately 60% of all US women over the age of 40 utilize mammography. Through the matrix of an imaging technology, this Population of Patients (POP) interacts with a population of approximately 20,000 physicians who interpret mammograms in the US. This latter Population of Diagnosticians (POD) operationally serves as the interface between an image-centric healthcare technology system and patient. Methods: using data collected from a large POD and POP based study, I evaluate the distribution of several ROC curve-related parameters in the POD and explore the health policy implications of a population ROC curve for mammography. Results and Conclusions: Principal Components Analysis suggests that two Binormal parameters are sufficient to explain variation in the POD and implies that the Binormal model is foundational to Health Policy Research in Mammography. A population ROC curve based on percentiles of the POD can be used to set targets to achieve national health policy goals. Medical Image Perception science provides the framework. Alternatively, a restrictive policy can be envisioned using performance criteria based on area. However, the data suggests this sort of policy would be too costly in terms of reduced healthcare service capacity in the US in the face of burgeoning demands.

Phylogeography of the American woodcock (Scolopax minor): Are management units based on band recovery data reflected in genetically based management units?

USGS Publications Warehouse

Rhymer, J.M.; McAuley, D.G.; Ziel, H.L.

2005-01-01

Information on population connectivity throughout the annual cycle has become more crucial, because populations of many migratory birds are in decline. One such species is the American Woodcock (Scolopax minor), which inhabits early-successional forests in eastern North America. Although band recoveries have proved useful for dividing populations of this game bird species into an Eastern Region and Central Region for management purposes, these data do not provide enough detail to determine the breeding population of origin of birds recovered on stopover and wintering areas. To obtain more fine-scale data, we undertook a phylogeographic study of American Woodcock populations throughout their primary breeding range in the eastern United States and Canada using mitochondrial DNA (mtDNA) sequences from the hypervariable control region I (CRI) and ND6 gene. Despite high haplotype diversity, nucleotide diversity was low and there was no phylogeographic structure among American Woodcock populations across the species range, with birds from many states and provinces in both management regions sharing identical haplotypes. Results suggest recent or ongoing gene flow among populations, with asymmetric movement of birds between migration flyways. As has been demonstrated for several other avian species in North America, American Woodcock appear to have undergone a rapid population expansion following the late Pleistocene glacial retreat. Thus, a combination of historical demographic factors and recent or ongoing gene flow mask any population structure based on mtDNA that might accrue from philopatry to breeding areas observed in studies of marked birds.

Understanding Disabled Childhoods: What Can We Learn from Population-Based Studies?

ERIC Educational Resources Information Center

Emerson, Eric

2012-01-01

This article illustrates the potential value of undertaking secondary analyses of large-scale population-based survey data to better inform our understanding of disabled childhoods. It is argued that while such approaches can never address the lived experience of growing up with disability, they can provide valuable insights into the ways in which…

Increased Risk for Substance Use-Related Problems in Autism Spectrum Disorders: A Population-Based Cohort Study

ERIC Educational Resources Information Center

Butwicka, Agnieszka; Långström, Niklas; Larsson, Henrik; Lundström, Sebastian; Serlachius, Eva; Almqvist, Catarina; Frisén, Louise; Lichtenstein, Paul

2017-01-01

Despite limited and ambiguous empirical data, substance use-related problems have been assumed to be rare among patients with autism spectrum disorders (ASD). Using Swedish population-based registers we identified 26,986 individuals diagnosed with ASD during 1973-2009, and their 96,557 non-ASD relatives. ASD, without diagnosed comorbidity of…

Medicare Part D Enrollment in a Biracial Community-Based Population of Older Adults

ERIC Educational Resources Information Center

Skarupski, Kimberly A.; Mendes de Leon, Carlos F.; Barnes, Lisa L.; Evans, Denis A.

2009-01-01

Purpose: The Medicare Prescription Drug Benefit (Part D) program debuted in January 2006. We ascertained the sociodemographic and health characteristics of Blacks and Whites who enrolled in the early stages of the program. Design and Methods: Data were collected between April 2006 and October 2007 from an ongoing population-based biracial study of…

Individual-based model formulation for cutthroat trout, Little Jones Creek, California

Treesearch

Steven F. Railsback; Bret C. Harvey

2001-01-01

This report contains the detailed formulation of an individual-based model (IBM) of cutthroat trout developed for three study sites on Little Jones Creek, Del Norte County, in northwestern California. The model was designed to support research on relations between habitat and fish population dynamics, the importance of small tributaries to trout populations, and the...

Development of Population-Based Resilience Measures in the Primary School Setting

ERIC Educational Resources Information Center

Sun, Jing; Stewart, Donald

2007-01-01

Purpose: The purpose of the population-based study in the paper is to report on progress in formulating instruments to measure children's resilience and associated protective factors in family, primary school and community contexts. Design/methodology/approach: In this paper a total of 2,794 students, 1,558 parents/caregivers, and 465 staff were…

Associated Medical Disorders and Disabilities in Children with Autistic Disorder: A Population-Based Study

ERIC Educational Resources Information Center

Kielinen, Marko; Rantala, Heikki; Timonen, Eija; Linna, Sirkka-Liisa; Moilanen, Irma

2004-01-01

A population-based survey was conducted among 152,732 Finnish children and adolescents aged under 16 years and living in northern Finland. Diagnoses and associated medical conditions were derived from the hospital and institutional records of this area. One hundred and eighty-seven children with DSM-IV autistic disorder were identified. Associated…

Population-based breast cancer screening in a primary care network

PubMed Central

Atlas, Steven J.; Ashburner, Jeffrey M.; Chang, Yuchiao; Lester, William T.; Barry, Michael J.; Grant, Richard W.

2013-01-01

Objective To assess up to 3-year follow-up of a health information technology system that facilitated population-based breast cancer screening. Study Design Cohort study with 2-year follow-up after completing a 1-year cluster randomized trial. Methods Women 42-69 years old receiving care within a 12-practice primary care network. The trial tested an integrated, non-visit-based population management informatics system that: 1) identified women overdue for mammograms, 2) connected them to primary care providers using a Web-based tool, 3) created automatically-generated outreach letters for patients specified by providers, 4) monitored for subsequent mammography scheduling and completion, and 5) provided practice delegates a list of women remaining unscreened for reminder phone calls. All practices also provided visit-based cancer screening reminders. Eligible women overdue for a mammogram during a one-year study period included those overdue at study start (prevalent cohort) or becoming overdue during follow-up (incident cohort). The main outcome measure was mammography completion rates over three years. Results Among 32,688 eligible women, 9,795 (30%) were overdue for screening including 4,487 in intervention and 5,308 in control practices. Intervention patients were somewhat younger, more likely to be non-Hispanic white, and have health insurance compared to control patients. Among patients in the prevalent cohort (n=6,697), adjusted completion rates were significantly higher among intervention compared to control patients after 3 years (51.7% vs. 45.8%, p=0.002). For patients in the incident cohort (n=3,098), adjusted completion rates after 2 years were 53.8% vs. 48.7%, p=0.052, respectively. Conclusions Population-based informatics systems can enable sustained increases in mammography screening rates beyond that seen with office-based visit reminders. PMID:23286611

Global trends in the incidence and prevalence of type 2 diabetes in children and adolescents: a systematic review and evaluation of methodological approaches.

PubMed

Fazeli Farsani, S; van der Aa, M P; van der Vorst, M M J; Knibbe, C A J; de Boer, A

2013-07-01

This study aimed to systematically review what has been reported on the incidence and prevalence of type 2 diabetes in children and adolescents, to scrutinise the methodological issues observed in the included studies and to prepare recommendations for future research and surveillances. PubMed, the Cochrane Database of Systematic Reviews, Scopus, EMBASE and Web of Science were searched from inception to February 2013. Population-based studies on incidence and prevalence of type 2 diabetes in children and adolescents were summarised and methodologically evaluated. Owing to substantial methodological heterogeneity and considerable differences in study populations a quantitative meta-analysis was not performed. Among 145 potentially relevant studies, 37 population-based studies met the inclusion criteria. Variations in the incidence and prevalence rates of type 2 diabetes in children and adolescents were mainly related to age of the study population, calendar time, geographical regions and ethnicity, resulting in a range of 0-330 per 100,000 person-years for incidence rates, and 0-5,300 per 100,000 population for prevalence rates. Furthermore, a substantial variation in the methodological characteristics was observed for response rates (60-96%), ascertainment rates (53-99%), diagnostic tests and criteria used to diagnose type 2 diabetes. Worldwide incidence and prevalence of type 2 diabetes in children and adolescents vary substantially among countries, age categories and ethnic groups and this can be explained by variations in population characteristics and methodological dissimilarities between studies.

Evaluation of Selection Bias in an Internet-based Study of Pregnancy Planners

PubMed Central

Hatch, Elizabeth E.; Hahn, Kristen A.; Wise, Lauren A.; Mikkelsen, Ellen M.; Kumar, Ramya; Fox, Matthew P.; Brooks, Daniel R.; Riis, Anders H.; Sorensen, Henrik Toft; Rothman, Kenneth J.

2016-01-01

Selection bias is a potential concern in all epidemiologic studies, but it is usually difficult to assess. Recently, concerns have been raised that internet-based prospective cohort studies may be particularly prone to selection bias. Although use of the internet is efficient and facilitates recruitment of subjects that are otherwise difficult to enroll, any compromise in internal validity would be of great concern. Few studies have evaluated selection bias in internet-based prospective cohort studies. Using data from the Danish Medical Birth Registry from 2008 to 2012, we compared six well-known perinatal associations (e.g., smoking and birth weight) in an inter-net-based preconception cohort (Snart Gravid n = 4,801) with the total population of singleton live births in the registry (n = 239,791). We used log-binomial models to estimate risk ratios (RRs) and 95% confidence intervals (CIs) for each association. We found that most results in both populations were very similar. For example, maternal obesity was associated with an increased risk of delivering a macrosomic infant in Snart Gravid (RR = 1.5; 95% CI: 1.2, 1.7) and the total population (RR = 1.5; 95% CI: 1.45, 1.53), and maternal smoking of >10 cigarettes per day was associated with a higher risk of low birth weight (RR = 2.7; 95% CI: 1.2, 5.9 vs. RR = 2.9; 95% CI: 2.6, 3.1) in Snart Gravid and the total population, respectively. We cannot be certain that our results would apply to other associations or different populations. Nevertheless, our results suggest that recruitment of reproductive aged women via the internet may be no more prone to selection bias than traditional methods of recruitment. PMID:26484423

A Venue-Based Approach to Reaching MSM, IDUs and the General Population with VCT: A Three Study Site in Kenya

PubMed Central

Singh, Kavita; Brodish, Paul; Mbai, Fiona; Kingola, Nzioki; Rinyuri, Agnes; Njeru, Carol; Mureithi, Patrick; Sambisa, William; Weir, Sharon

2014-01-01

A venue-based HIV prevention study which included Voluntary Counseling and Testing (VCT) was conducted in three diverse areas of Kenya— Malindi, Nanyuki and Rachounyo. Aims of the study were to: 1) assess the acceptability of VCT for the general population, men who have sex with men (MSM), and injecting drug users (IDUs) within the context of a venue-based approach; 2) determine if there were differences between those agreeing and not agreeing to testing; and 3) study factors associated with being HIV positive. Approximately 98% of IDUs and 97% of MSM agreed to VCT, providing evidence that populations with little access to services and whose behaviors are stigmatized and often considered illegal in their countries can be reached with needed HIV prevention services. Acceptability of VCT in the general population ranged from 60% in Malindi to 48% in Nanyuki. There were a few significant differences between those accepting and declining testing. Notably in Rachuonyo and Malindi those reporting multiple partners were more likely to accept testing. There was also evidence that riskier sexual behavior was associated with being HIV positive for both men in Rachounyo and women in Malindi. Overall HIV prevalence was higher among the individuals in this study compared to individuals sampled in the 2008–2009 Kenya Demographic and Health Survey, indicating the method is an appropriate means to reach the highest risk individuals including stigmatized populations. PMID:22198312

A simple risk score for identifying individuals with impaired fasting glucose in the Southern Chinese population.

PubMed

Wang, Hui; Liu, Tao; Qiu, Quan; Ding, Peng; He, Yan-Hui; Chen, Wei-Qing

2015-01-23

This study aimed to develop and validate a simple risk score for detecting individuals with impaired fasting glucose (IFG) among the Southern Chinese population. A sample of participants aged ≥20 years and without known diabetes from the 2006-2007 Guangzhou diabetes cross-sectional survey was used to develop separate risk scores for men and women. The participants completed a self-administered structured questionnaire and underwent simple clinical measurements. The risk scores were developed by multiple logistic regression analysis. External validation was performed based on three other studies: the 2007 Zhuhai rural population-based study, the 2008-2010 Guangzhou diabetes cross-sectional study and the 2007 Tibet population-based study. Performance of the scores was measured with the Hosmer-Lemeshow goodness-of-fit test and ROC c-statistic. Age, waist circumference, body mass index and family history of diabetes were included in the risk score for both men and women, with the additional factor of hypertension for men. The ROC c-statistic was 0.70 for both men and women in the derivation samples. Risk scores of ≥28 for men and ≥18 for women showed respective sensitivity, specificity, positive predictive value and negative predictive value of 56.6%, 71.7%, 13.0% and 96.0% for men and 68.7%, 60.2%, 11% and 96.0% for women in the derivation population. The scores performed comparably with the Zhuhai rural sample and the 2008-2010 Guangzhou urban samples but poorly in the Tibet sample. The performance of pre-existing USA, Shanghai, and Chengdu risk scores was poorer in our population than in their original study populations. The results suggest that the developed simple IFG risk scores can be generalized in Guangzhou city and nearby rural regions and may help primary health care workers to identify individuals with IFG in their practice.

A Simple Risk Score for Identifying Individuals with Impaired Fasting Glucose in the Southern Chinese Population

PubMed Central

Wang, Hui; Liu, Tao; Qiu, Quan; Ding, Peng; He, Yan-Hui; Chen, Wei-Qing

2015-01-01

This study aimed to develop and validate a simple risk score for detecting individuals with impaired fasting glucose (IFG) among the Southern Chinese population. A sample of participants aged ≥20 years and without known diabetes from the 2006–2007 Guangzhou diabetes cross-sectional survey was used to develop separate risk scores for men and women. The participants completed a self-administered structured questionnaire and underwent simple clinical measurements. The risk scores were developed by multiple logistic regression analysis. External validation was performed based on three other studies: the 2007 Zhuhai rural population-based study, the 2008–2010 Guangzhou diabetes cross-sectional study and the 2007 Tibet population-based study. Performance of the scores was measured with the Hosmer-Lemeshow goodness-of-fit test and ROC c-statistic. Age, waist circumference, body mass index and family history of diabetes were included in the risk score for both men and women, with the additional factor of hypertension for men. The ROC c-statistic was 0.70 for both men and women in the derivation samples. Risk scores of ≥28 for men and ≥18 for women showed respective sensitivity, specificity, positive predictive value and negative predictive value of 56.6%, 71.7%, 13.0% and 96.0% for men and 68.7%, 60.2%, 11% and 96.0% for women in the derivation population. The scores performed comparably with the Zhuhai rural sample and the 2008–2010 Guangzhou urban samples but poorly in the Tibet sample. The performance of pre-existing USA, Shanghai, and Chengdu risk scores was poorer in our population than in their original study populations. The results suggest that the developed simple IFG risk scores can be generalized in Guangzhou city and nearby rural regions and may help primary health care workers to identify individuals with IFG in their practice. PMID:25625405

Revisiting typhoid fever surveillance in low and middle income countries: lessons from systematic literature review of population-based longitudinal studies.

PubMed

Mogasale, Vittal; Mogasale, Vijayalaxmi V; Ramani, Enusa; Lee, Jung Seok; Park, Ju Yeon; Lee, Kang Sung; Wierzba, Thomas F

2016-01-29

The control of typhoid fever being an important public health concern in low and middle income countries, improving typhoid surveillance will help in planning and implementing typhoid control activities such as deployment of new generation Vi conjugate typhoid vaccines. We conducted a systematic literature review of longitudinal population-based blood culture-confirmed typhoid fever studies from low and middle income countries published from 1(st) January 1990 to 31(st) December 2013. We quantitatively summarized typhoid fever incidence rates and qualitatively reviewed study methodology that could have influenced rate estimates. We used meta-analysis approach based on random effects model in summarizing the hospitalization rates. Twenty-two papers presented longitudinal population-based and blood culture-confirmed typhoid fever incidence estimates from 20 distinct sites in low and middle income countries. The reported incidence and hospitalizations rates were heterogeneous as well as the study methodology across the sites. We elucidated how the incidence rates were underestimated in published studies. We summarized six categories of under-estimation biases observed in these studies and presented potential solutions. Published longitudinal typhoid fever studies in low and middle income countries are geographically clustered and the methodology employed has a potential for underestimation. Future studies should account for these limitations.

"Perspectives on financing population-based health care towards Universal Health Coverage among employed individuals in Ghanzi district, Botswana: A qualitative study".

PubMed

Mbogo, Barnabas Africanus; McGill, Deborah

2016-08-19

Globally, about 150 million people experience catastrophic healthcare expenditure services annually. Among low and middle income countries, out-of-pocket expenditure pushes about 100 million people into poverty annually. In Botswana, 83 % of the general population and 58 % of employed individuals do not have medical aid coverage. Moreover, inequity allocation of financial resources between health services suggests marginalization of population-based health care services (i.e. diseases prevention and health promotion). The purpose of the study is to explore perspectives on employed individuals regarding financing population based health care interventions towards Universal Health Coverage (UHC) in order to make recommendations to the Ministry of Health on health financing options to cover population-based health services. A qualitative design grounded in interpretivist epistemology through social constructivism lens was critical for exploring perspectives of employed individuals. Through purposive and snowballing sampling techniques, a total of 15 respondents including 8 males and 7 females were recruited and interviewed using a semi-structured format. Their age ranged from 23 to 59 years with a median of 36 years. Data was analyzed using Thematic Content Analysis technique. Use of social constructivism lens enabled to classify emerging themes into population coverage, health services coverage and financial protection issues. Despite broad understanding of health coverage schemes among participants, knowledge appears insignificant in increasing enrolment. Participants indicated limited understanding of UHC concepts, however showed willingness to embrace UHC upon brief description. Main thematic issues raised include: exclusion of population-based health services from coverage scheme; disparity in financial protection and health services coverage among enrollees; inability to sustain contracted employees; and systematic exclusion of unemployed individuals and informal sector employees. Increasing enrolment in health coverage schemes requires targeted campaign for information dissemination through use of myriads mass media including: social networks, TV, Radio and others. Moreover, re-designing health insurance schemes is critical in order to include population-based interventions; expand uptake of unemployed and informal sector employees; flexibility in monthly premiums payment plan and use of technology to increase access to payment points. Further study need to evaluate the content of health financing policy in Botswana measured against the World Health Organization Universal Health Coverage conceptual requirements for Low and Middle Income Countries.

Influence of population versus convenience sampling on sample characteristics in studies of cognitive aging.

PubMed

Brodaty, Henry; Mothakunnel, Annu; de Vel-Palumbo, Melissa; Ames, David; Ellis, Kathryn A; Reppermund, Simone; Kochan, Nicole A; Savage, Greg; Trollor, Julian N; Crawford, John; Sachdev, Perminder S

2014-01-01

We examined whether differences in findings of studies examining mild cognitive impairment (MCI) were associated with recruitment methods by comparing sample characteristics in two contemporaneous Australian studies, using population-based and convenience sampling. The Sydney Memory and Aging Study invited participants randomly from the electoral roll in defined geographic areas in Sydney. The Australian Imaging, Biomarkers and Lifestyle Study of Ageing recruited cognitively normal (CN) individuals via media appeals and MCI participants via referrals from clinicians in Melbourne and Perth. Demographic and cognitive variables were harmonized, and similar diagnostic criteria were applied to both samples retrospectively. CN participants recruited via convenience sampling were younger, better educated, more likely to be married and have a family history of dementia, and performed better cognitively than those recruited via population-based sampling. MCI participants recruited via population-based sampling had better memory performance and were less likely to carry the apolipoprotein E ε4 allele than clinically referred participants but did not differ on other demographic variables. A convenience sample of normal controls is likely to be younger and better functioning and that of an MCI group likely to perform worse than a purportedly random sample. Sampling bias should be considered when interpreting findings. Copyright © 2014 Elsevier Inc. All rights reserved.

The bidirectional association between oral cancer and esophageal cancer: A population-based study in Taiwan over a 28-year period

PubMed Central

Lu, Chang-Hsien; Huang, Cih-En; Chen, Min-Chi

2017-01-01

Previous studies have revealed that patients with oral or esophageal cancer are at higher risk for subsequently developing a second primary malignancy. However, it remains to be determined what association exists between oral cancer and esophageal cancer particularly in Asian countries where squamous cell carcinoma is the predominant type of esophageal cancer. A population-based study was carried out in Taiwan, where the incidence rates of both oral and esophageal squamous cell carcinomas are high, to test the hypothesis that oral cancer or esophageal cancer predisposes an individual to developing the other form of cancer. Our results showed that patients with primary oral cancer (n=45,859) had ten times the risk of second esophageal cancer compared to the general population. Within the same cohort, the reciprocal risk of oral cancer as a second primary in primary esophageal cancer patients (n=16,658) was also increased seven-fold. The bidirectional relationship suggests common risk factors between these two cancers. The present study is not only the first population-based study in Asia to validate the reciprocal relationship between oral and esophageal squamous cell carcinomas, but also will aid in the appropriate selection of high-risk patients for a future follow-up surveillance program. PMID:28562351

Serum brain-derived neurotrophic factor levels in subjects with major depressive disorder with previous suicide attempt: A population-based study.

PubMed

Pedrotti Moreira, Fernanda; Borges, Cristiane Jackson; Wiener, Carolina David; da Silva, Paula Moraes; Portela, Luis Valmor; Lara, Diogo R; da Silva, Ricardo Azevedo; de Mattos Souza, Luciano Dias; Jansen, Karen; Oses, Jean Pierre

2018-04-01

Major depressive disorders (MDD) and suicide are significant public health concerns. Recent studies have been demonstrated that alterations in Brain Derived Neurotrophic Factor (BDNF) can be associated with this psychiatric disorders, MDD and suicide. Thus, the aim of this study was to evaluate differences in serum levels in individuals with MDD and with or without suicide attempt (SA), from a population-based sample. This was a paired cross-sectional study nested in a population-based study. The psychopathology screen was performed with the Mini-International Neuropsychiatric Interview (MINI). The total population of the sample consisted of 147 subjects distributed in three groups: 49 healthy controls, 49 subjects with MDD and 49 subjects with MDD and SA (MDD + SA). The BDNF serum levels were significantly reduced in subjects with MDD and MDD + SA compared to the healthy controls. However, there were no significant differences between the MDD and MDD + SA groups with respect to BDNF serum levels. These results suggest that SA did not interfere in the serum levels of BDNF, indicating that this neurotrophin may be related to the diagnosis of MDD and not to suicide attempt. Copyright © 2017 Elsevier B.V. All rights reserved.

The bidirectional association between oral cancer and esophageal cancer: A population-based study in Taiwan over a 28-year period.

PubMed

Lee, Kuan-Der; Wang, Ting-Yao; Lu, Chang-Hsien; Huang, Cih-En; Chen, Min-Chi

2017-07-04

Previous studies have revealed that patients with oral or esophageal cancer are at higher risk for subsequently developing a second primary malignancy. However, it remains to be determined what association exists between oral cancer and esophageal cancer particularly in Asian countries where squamous cell carcinoma is the predominant type of esophageal cancer. A population-based study was carried out in Taiwan, where the incidence rates of both oral and esophageal squamous cell carcinomas are high, to test the hypothesis that oral cancer or esophageal cancer predisposes an individual to developing the other form of cancer. Our results showed that patients with primary oral cancer (n=45,859) had ten times the risk of second esophageal cancer compared to the general population. Within the same cohort, the reciprocal risk of oral cancer as a second primary in primary esophageal cancer patients (n=16,658) was also increased seven-fold. The bidirectional relationship suggests common risk factors between these two cancers. The present study is not only the first population-based study in Asia to validate the reciprocal relationship between oral and esophageal squamous cell carcinomas, but also will aid in the appropriate selection of high-risk patients for a future follow-up surveillance program.

Prevalence and correlations of lower urinary tract symptoms, erectile dysfunction and incontinence in men from a multiethnic Asian population: Results of a regional population-based survey and comparison with industrialized nations.

PubMed

Mariappan, Paramananthan; Chong, Wooi Loong

2006-12-01

To determine, in a population-based survey, the prevalence of lower urinary tract symptoms (LUTS), erectile dysfunction (ED) and incontinence in community-dwelling men in multiethnic Malaysia, as currently available Western demographic data might not be applicable in the Asian population. A cross-sectional population-based survey was carried out in the State of Penang, Malaysia, with a target population of men aged > or = 40 years. Using a multistage study design, random systematic sampling was used to represent the target population, who were weighted based on ethnicity and rural-urban ratios so as to represent the general population distribution. Trained field-workers conducted direct interviews and administered the American Urological Association Symptom Index (AUA-SI), the International Index of Erectile Function (IIEF-5) questionnaire and questions on incontinence based on the International Continence Society 2002 definition. In all, 418 men aged > or = 40 years were interviewed, of whom 353 completed the AUA-SI questionnaire (84.5% response rate). The prevalence of mild, moderate and severe LUTS was 80.6%, 6% and 0.3%, respectively. The prevalent symptoms were frequency and nocturia. There was moderate and severe ED in 45.9% of men, whereas incontinence was reported by 8.2%. The AUA-SI correlated strongly with age (R = 0.291, P < 0.001), IIEF-5 (R = - 0.265, P < 0.001) and diabetes mellitus. The prevalence and severity of LUTS, ED and incontinence increased with age in this multiethnic Asian population, in which ED correlated strongly with LUTS. Compared to the Western population, the prevalence of LUTS was significantly lower, while the prevalence of ED and incontinence were comparable.

Effective population size and genetic structure of a Piute ground squirrel (Spermophilus mollis) population

USGS Publications Warehouse

Antolin, Michael F.; Van Horne, Beatrice; Berger, Michael D.

2001-01-01

Piute ground squirrels (Spermophilus mollis) are distributed continuously in habitat dominated by native shrubs and perennial grasses in the Snake River Birds of Prey National Conservation Area in Idaho, U.S.A. This habitat is being fragmented and replaced by exotic annual plants, changing it to a wildfire-dominated system that provides poor habitat for ground squirrels. To assess potential effects of this fragmentation on ground squirrel populations, we combined an estimate of effective population size (Ne) based upon a demographic study with a population genetic analysis. The study area included three subpopulations separated from each other by 8–13 km. The ratio of effective population size to census number (Ne/N) was 0.57. Combining Ne/N with dispersal distances from a radio-tracking study, we calculated that neighborhood size was 62.2 ha, which included between 204 and 480 individuals. Our population genetic analysis (based on randomly amplified polymorphic DNA (RAPD) and microsatellite markers) showed relatively low levels of genetic differentiation (Qpopulations 0.07–0.10) between subpopulations and no inbreeding within subpopulations (f = 0.0003). These estimates of population subdivision translate into an effective migration rate (Nem) of 2.3–3.3 per year, which represents a high level of gene flow. Invasion by exotics will reduce the overall productivity of the habitat, and will lead to isolation among subpopulations if favorable habitat patches become isolated.

Enantiomorphism and rule similarity in the astigmatism axes of fellow eyes: A population-based study.

PubMed

Hashemi, Hassan; Asharlous, Amir; Yekta, Abbasali; Ostadimoghaddam, Hadi; Mohebi, Masumeh; Aghamirsalim, Mohamadreza; Khabazkhoob, Mehdi

2018-04-03

To evaluate the relationship patterns between astigmatism axes of fellow eyes (rule similarity and symmetry) and to determine the prevalence of each pattern in the studied population. This population-based study was conducted in 2015 in Iran. All participants had tests for visual acuity, objective refraction, subjective refraction (if cooperative), and assessment of eye health at the slit-lamp. Axis symmetry was based on two different patterns: direct (equal axes) and mirror (mirror image symmetry) or enantiomorphism. Bilateral astigmatism was classified as isorule if fellow eyes had the same orientation (e.g. both eyes were with-the-rule) and as anisorule if otherwise. Of the total cases of bilateral astigmatism, 80% were isorule, and in the studied population, the prevalence of isorule and anisorule astigmatism was 14.89% and 3.53%, respectively. The prevalence of isorule increased with age (p<0.001). The prevalence of both isorule and anisorule increased at higher degrees of spherical ametropia (p<0.001). Median inter-ocular axis difference was 10° in mirror symmetry and 20° in direct symmetry with no significant difference between two genders (p>0.288). Both symmetry patterns reduced with age (p<0.001). Among cases of bilateral astigmatism, 15.5% and 19.8% had exact direct and mirror symmetry, respectively. Bilateral astigmatism is mainly isorule in the population and anisorule astigmatism is rare. The enantiomorphism is the most common pattern in the population of bilateral astigmatism. Copyright © 2018 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

Temporal trends in prevalence, incidence, and mortality for rheumatoid arthritis in Quebec, Canada: a population-based study.

PubMed

Jean, Sonia; Hudson, Marie; Gamache, Philippe; Bessette, Louis; Fortin, Paul R; Boire, Gilles; Bernatsky, Sasha

2017-12-01

Health administrative data are a potentially efficient resource to conduct population-based research and surveillance, including trends in incidence and mortality over time. Our objective was to explore time trends in incidence and mortality for rheumatoid arthritis (RA), as well as estimating period prevalence. Our RA case definition was based on one or more hospitalizations with a RA diagnosis code, or three or more RA physician-billing codes, over 2 years, with at least one RA billing code by a rheumatologist, orthopedic surgeon, or internist. To identify incident cases, a "run-in" period of 5 years (1996-2000) was used to exclude prevalent cases. Crude age and sex-specific incidence rates were calculated (using data from 2001 to 2015), and sex-specific incidence rates were also standardized to the 2001 age structure of the Quebec population. We linked the RA cohort (both prevalent and incident patients) to the vital statistics registry, and standardized mortality rate ratios were generated. Negative binomial regression was used to test for linear change in standardized incidence rates and mortality ratios. The linear trends in standardized incidence rates did not show significant change over the study period. Mortality in RA was significantly higher than the general population and this remained true throughout the study period. Our prevalence estimate suggested 0.8% of the Quebec population may be affected by RA. RA incidence appeared relatively stable, and mortality was substantially higher in RA versus the general population and remained so over the study period. This suggests the need to optimize long-term RA outcomes.

Population structure of humpback whales in the western and central South Pacific Ocean as determined by vocal exchange among populations.

PubMed

Garland, Ellen C; Goldizen, Anne W; Lilley, Matthew S; Rekdahl, Melinda L; Garrigue, Claire; Constantine, Rochelle; Hauser, Nan Daeschler; Poole, M Michael; Robbins, Jooke; Noad, Michael J

2015-08-01

For cetaceans, population structure is traditionally determined by molecular genetics or photographically identified individuals. Acoustic data, however, has provided information on movement and population structure with less effort and cost than traditional methods in an array of taxa. Male humpback whales (Megaptera novaeangliae) produce a continually evolving vocal sexual display, or song, that is similar among all males in a population. The rapid cultural transmission (the transfer of information or behavior between conspecifics through social learning) of different versions of this display between distinct but interconnected populations in the western and central South Pacific region presents a unique way to investigate population structure based on the movement dynamics of a song (acoustic) display. Using 11 years of data, we investigated an acoustically based population structure for the region by comparing stereotyped song sequences among populations and years. We used the Levenshtein distance technique to group previously defined populations into (vocally based) clusters based on the overall similarity of their song display in space and time. We identified the following distinct vocal clusters: western cluster, 1 population off eastern Australia; central cluster, populations around New Caledonia, Tonga, and American Samoa; and eastern region, either a single cluster or 2 clusters, one around the Cook Islands and the other off French Polynesia. These results are consistent with the hypothesis that each breeding aggregation represents a distinct population (each occupied a single, terminal node) in a metapopulation, similar to the current understanding of population structure based on genetic and photo-identification studies. However, the central vocal cluster had higher levels of song-sharing among populations than the other clusters, indicating that levels of vocal connectivity varied within the region. Our results demonstrate the utility and value of using culturally transmitted vocal patterns as a way of defining connectivity to infer population structure. We suggest vocal patterns be incorporated by the International Whaling Commission in conjunction with traditional methods in the assessment of structure. © 2015, Society for Conservation Biology.

The Relation Between Inflation in Type-I and Type-II Error Rate and Population Divergence in Genome-Wide Association Analysis of Multi-Ethnic Populations.

PubMed

Derks, E M; Zwinderman, A H; Gamazon, E R

2017-05-01

Population divergence impacts the degree of population stratification in Genome Wide Association Studies. We aim to: (i) investigate type-I error rate as a function of population divergence (F ST ) in multi-ethnic (admixed) populations; (ii) evaluate the statistical power and effect size estimates; and (iii) investigate the impact of population stratification on the results of gene-based analyses. Quantitative phenotypes were simulated. Type-I error rate was investigated for Single Nucleotide Polymorphisms (SNPs) with varying levels of F ST between the ancestral European and African populations. Type-II error rate was investigated for a SNP characterized by a high value of F ST . In all tests, genomic MDS components were included to correct for population stratification. Type-I and type-II error rate was adequately controlled in a population that included two distinct ethnic populations but not in admixed samples. Statistical power was reduced in the admixed samples. Gene-based tests showed no residual inflation in type-I error rate.

Differences in reported sepsis incidence according to study design: a literature review.

PubMed

Mariansdatter, Saga Elise; Eiset, Andreas Halgreen; Søgaard, Kirstine Kobberøe; Christiansen, Christian Fynbo

2016-10-12

Sepsis and severe sepsis are common conditions in hospital settings, and are associated with high rates of morbidity and mortality, but reported incidences vary considerably. In this literature review, we describe the variation in reported population-based incidences of sepsis and severe sepsis. We also examine methodological and demographic differences between studies that may explain this variation. We carried out a literature review searching three major databases and reference lists of relevant articles, to identify all original studies reporting the incidence of sepsis or severe sepsis in the general population. Two authors independently assessed all articles, and the final decision to exclude an article was reached by consensus. We extracted data according to predetermined variables, including study country, sepsis definition, and data source. We then calculated descriptive statistics for the reported incidences of sepsis and severe sepsis. The studies were classified according to the method used to identify cases of sepsis or severe sepsis: chart-based (i.e. review of patient charts) or code-based (i.e. predetermined International Classification of Diseases [ICD] codes). Among 482 articles initially screened, we identified 23 primary publications reporting incidence of sepsis and/or severe sepsis in the general population. The reported incidences ranged from 74 to 1180 per 100,000 person-years and 3 to 1074 per 100,000 person-years for sepsis and severe sepsis, respectively. Most chart-based studies used the Bone criteria (or a modification hereof) and Protein C Worldwide Evaluation in Severe Sepsis (PROWESS) study criteria to identify cases of sepsis and severe sepsis. Most code-based studies used ICD-9 codes, but the number of codes used ranged from 1 to more than 1200. We found that the incidence varied according to how sepsis was identified (chart-based vs. code-based), calendar year, data source, and world region. The reported incidences of sepsis and severe sepsis in the general population varied greatly between studies. Such differences may be attributable to differences in the methods used to collect the data, the study period, or the world region where the study was undertaken. This finding highlights the importance of standardised definitions and acquisition of data regarding sepsis and severe sepsis.

Hypertension in Germany.

PubMed

Neuhauser, Hannelore; Diederichs, Claudia; Boeing, Heiner; Felix, Stephan B; Jünger, Claus; Lorbeer, Roberto; Meisinger, Christine; Peters, Annette; Völzke, Henry; Weikert, Cornelia; Wild, Philipp; Dörr, Marcus

2016-12-02

Hypertension is a key risk factor. However, population data based on blood pressure measurements in Germany are scarce. Standardized blood pressure (BP) measurements and medication data from seven population-based studies conducted in Germany between 1994 and 2012 (66 845 participants, 25-74 years) were analyzed: the EPICPotsdam study (1994-1998, EPIC), the KORA-S4 Study (1999-2001) in Augsburg, and the Gutenberg Health Study (2007-2012, GHS) in Mainz/Mainz-Bingen provided data for descriptive comparisons. Time trends were analyzed based on identical study regions for the German National Health Interview and Examination Survey 1998 (BGS98) and the German Health Examination Survey for Adults (2008-11, DEGS1) as well as the Study of Health in Pomerania (SHIP) in Northeast Germany (1997-2001) and the SHIP-TREND study (2008-2012). BP data were adjusted for study-specific measurement devices based on calibration studies. After adjustment for study-specific measurement devices, mean systolic and diastolic BP values were lower and treatment proportions higher in recent (2007-2012) compared to older (1994-2001) studies. Mean BP decrease was most pronounced (systolic ≥ 10 mmHg) in the elderly (55-74 years). The regional SHIP-TREND data for Northeast Germany showed a decrease in mean systolic BP in young men aged 25 to 34 years; on a national level according to the DEGS1 data, however, no such decrease was observed for this group. New data add evidence for lower BP in Germany. However, the prevention potential remains high. Future research based on population-based data should place a special focus on blood pressure data in young men.

The protocols for the 10/66 dementia research group population-based research programme.

PubMed

Prince, Martin; Ferri, Cleusa P; Acosta, Daisy; Albanese, Emiliano; Arizaga, Raul; Dewey, Michael; Gavrilova, Svetlana I; Guerra, Mariella; Huang, Yueqin; Jacob, K S; Krishnamoorthy, E S; McKeigue, Paul; Rodriguez, Juan Llibre; Salas, Aquiles; Sosa, Ana Luisa; Sousa, Renata M M; Stewart, Robert; Uwakwe, Richard

2007-07-20

Latin America, China and India are experiencing unprecedentedly rapid demographic ageing with an increasing number of people with dementia. The 10/66 Dementia Research Group's title refers to the 66% of people with dementia that live in developing countries and the less than one tenth of population-based research carried out in those settings. This paper describes the protocols for the 10/66 population-based and intervention studies that aim to redress this imbalance. Cross-sectional comprehensive one phase surveys have been conducted of all residents aged 65 and over of geographically defined catchment areas in ten low and middle income countries (India, China, Nigeria, Cuba, Dominican Republic, Brazil, Venezuela, Mexico, Peru and Argentina), with a sample size of between 1000 and 3000 (generally 2000). Each of the studies uses the same core minimum data set with cross-culturally validated assessments (dementia diagnosis and subtypes, mental disorders, physical health, anthropometry, demographics, extensive non communicable disease risk factor questionnaires, disability/functioning, health service utilisation, care arrangements and caregiver strain). Nested within the population based studies is a randomised controlled trial of a caregiver intervention for people with dementia and their families (ISRCTN41039907; ISRCTN41062011; ISRCTN95135433; ISRCTN66355402; ISRCTN93378627; ISRCTN94921815). A follow up of 2.5 to 3.5 years will be conducted in 7 countries (China, Cuba, Dominican Republic, Venezuela, Mexico, Peru and Argentina) to assess risk factors for incident dementia, stroke and all cause and cause-specific mortality; verbal autopsy will be used to identify causes of death. The 10/66 DRG baseline population-based studies are nearly complete. The incidence phase will be completed in 2009. All investigators are committed to establish an anonymised file sharing archive with monitored public access. Our aim is to create an evidence base to empower advocacy, raise awareness about dementia, and ensure that the health and social care needs of older people are anticipated and met.

The protocols for the 10/66 dementia research group population-based research programme

PubMed Central

Prince, Martin; Ferri, Cleusa P; Acosta, Daisy; Albanese, Emiliano; Arizaga, Raul; Dewey, Michael; Gavrilova, Svetlana I; Guerra, Mariella; Huang, Yueqin; Jacob, KS; Krishnamoorthy, ES; McKeigue, Paul; Rodriguez, Juan Llibre; Salas, Aquiles; Sosa, Ana Luisa; Sousa, Renata MM; Stewart, Robert; Uwakwe, Richard

2007-01-01

Background Latin America, China and India are experiencing unprecedentedly rapid demographic ageing with an increasing number of people with dementia. The 10/66 Dementia Research Group's title refers to the 66% of people with dementia that live in developing countries and the less than one tenth of population-based research carried out in those settings. This paper describes the protocols for the 10/66 population-based and intervention studies that aim to redress this imbalance. Methods/design Cross-sectional comprehensive one phase surveys have been conducted of all residents aged 65 and over of geographically defined catchment areas in ten low and middle income countries (India, China, Nigeria, Cuba, Dominican Republic, Brazil, Venezuela, Mexico, Peru and Argentina), with a sample size of between 1000 and 3000 (generally 2000). Each of the studies uses the same core minimum data set with cross-culturally validated assessments (dementia diagnosis and subtypes, mental disorders, physical health, anthropometry, demographics, extensive non communicable disease risk factor questionnaires, disability/functioning, health service utilisation, care arrangements and caregiver strain). Nested within the population based studies is a randomised controlled trial of a caregiver intervention for people with dementia and their families (ISRCTN41039907; ISRCTN41062011; ISRCTN95135433; ISRCTN66355402; ISRCTN93378627; ISRCTN94921815). A follow up of 2.5 to 3.5 years will be conducted in 7 countries (China, Cuba, Dominican Republic, Venezuela, Mexico, Peru and Argentina) to assess risk factors for incident dementia, stroke and all cause and cause-specific mortality; verbal autopsy will be used to identify causes of death. Discussion The 10/66 DRG baseline population-based studies are nearly complete. The incidence phase will be completed in 2009. All investigators are committed to establish an anonymised file sharing archive with monitored public access. Our aim is to create an evidence base to empower advocacy, raise awareness about dementia, and ensure that the health and social care needs of older people are anticipated and met. PMID:17659078

Count data, detection probabilities, and the demography, dynamics, distribution, and decline of amphibians.

PubMed

Schmidt, Benedikt R

2003-08-01

The evidence for amphibian population declines is based on count data that were not adjusted for detection probabilities. Such data are not reliable even when collected using standard methods. The formula C = Np (where C is a count, N the true parameter value, and p is a detection probability) relates count data to demography, population size, or distributions. With unadjusted count data, one assumes a linear relationship between C and N and that p is constant. These assumptions are unlikely to be met in studies of amphibian populations. Amphibian population data should be based on methods that account for detection probabilities.

Simulated effects of recruitment variability, exploitation, and reduced habitat area on the muskellunge population in Shoepack Lake, Voyageurs National Park, Minnesota

USGS Publications Warehouse

Frohnauer, N.K.; Pierce, C.L.; Kallemeyn, L.W.

2007-01-01

The genetically unique population of muskellunge Esox masquinongy inhabiting Shoepack Lake in Voyageurs National Park, Minnesota, is potentially at risk for loss of genetic variability and long-term viability. Shoepack Lake has been subject to dramatic surface area changes from the construction of an outlet dam by beavers Castor canadensis and its subsequent failure. We simulated the long-term dynamics of this population in response to recruitment variation, increased exploitation, and reduced habitat area. We then estimated the effective population size of the simulated population and evaluated potential threats to long-term viability, based on which we recommend management actions to help preserve the long-term viability of the population. Simulations based on the population size and habitat area at the beginning of a companion study resulted in an effective population size that was generally above the threshold level for risk of loss of genetic variability, except when fishing mortality was increased. Simulations based on the reduced habitat area after the beaver dam failure and our assumption of a proportional reduction in population size resulted in an effective population size that was generally below the threshold level for risk of loss of genetic variability. Our results identified two potential threats to the long-term viability of the Shoepack Lake muskellunge population, reduction in habitat area and exploitation. Increased exploitation can be prevented through traditional fishery management approaches such as the adoption of no-kill, barbless hook, and limited entry regulations. Maintenance of the greatest possible habitat area and prevention of future habitat area reductions will require maintenance of the outlet dam built by beavers. Our study should enhance the long-term viability of the Shoepack Lake muskellunge population and illustrates a useful approach for other unique populations. ?? Copyright by the American Fisheries Society 2007.

The Forgotten Learning Disability – Epidemiology of Written Language Disorder in a Population-Based Birth Cohort (1976-1982), Rochester, Minnesota

PubMed Central

Katusic, Slavica K.; Colligan, Robert C.; Weaver, Amy L.; Barbaresi, William J.

2009-01-01

OBJECTIVE The aim of this study was to report the incidence rates and other epidemiologic characterizations of Written Language Disorder (WLD). There have been no epidemiologic studies on the incidence of WLD in the United States and the use of a population-based birth cohort, longitudinally followed, is the most powerful method to reach this objective. METHODS In this population-based, retrospective birth cohort study, subjects included 5718 children born 1976-1982 in Rochester, Minnesota who remained in the community after age 5 years. Records from all public and nonpublic schools, medical facilities, and private tutorial services were reviewed and results of all individually administered IQ and achievement tests, and extensive medical, educational, and socioeconomic information were collected. The essential features of writing problems from the DSM-IV-TR were included in our operationalized definition of WLD. WLD incident cases were established using research criteria based on 3 formulas (regression-based discrepancy, non-regression-based discrepancy, low achievement). RESULTS Cumulative incidence rates of WLD varied from 6.9% to 14.7% depending on the formula. Boys were 2-3 times more likely to be affected than girls, regardless of the formula. Among all WLD cases (N=806), 25% (N=203) had WLD without Reading Disability (RD). Specifics of the writing problems were identified for 87% (N=702) of WLD cases. CONCLUSION In this population-based birth cohort of school aged children, WLD was at least as frequent as RD, and significantly more frequent among boys than girls. PMID:19403496

Estimating the population density of the Asian tapir (Tapirus indicus) in a selectively logged forest in Peninsular Malaysia.

PubMed

Rayan, D Mark; Mohamad, Shariff Wan; Dorward, Leejiah; Aziz, Sheema Abdul; Clements, Gopalasamy Reuben; Christopher, Wong Chai Thiam; Traeholt, Carl; Magintan, David

2012-12-01

The endangered Asian tapir (Tapirus indicus) is threatened by large-scale habitat loss, forest fragmentation and increased hunting pressure. Conservation planning for this species, however, is hampered by a severe paucity of information on its ecology and population status. We present the first Asian tapir population density estimate from a camera trapping study targeting tigers in a selectively logged forest within Peninsular Malaysia using a spatially explicit capture-recapture maximum likelihood based framework. With a trap effort of 2496 nights, 17 individuals were identified corresponding to a density (standard error) estimate of 9.49 (2.55) adult tapirs/100 km(2) . Although our results include several caveats, we believe that our density estimate still serves as an important baseline to facilitate the monitoring of tapir population trends in Peninsular Malaysia. Our study also highlights the potential of extracting vital ecological and population information for other cryptic individually identifiable animals from tiger-centric studies, especially with the use of a spatially explicit capture-recapture maximum likelihood based framework. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

Dengue fever spreading based on probabilistic cellular automata with two lattices

NASA Astrophysics Data System (ADS)

Pereira, F. M. M.; Schimit, P. H. T.

2018-06-01

Modeling and simulation of mosquito-borne diseases have gained attention due to a growing incidence in tropical countries in the past few years. Here, we study the dengue spreading in a population modeled by cellular automata, where there are two lattices to model the human-mosquitointeraction: one lattice for human individuals, and one lattice for mosquitoes in order to enable different dynamics in populations. The disease considered is the dengue fever with one, two or three different serotypes coexisting in population. Although many regions exhibit the incidence of only one serotype, here we set a complete framework to also study the occurrence of two and three serotypes at the same time in a population. Furthermore, the flexibility of the model allows its use to other mosquito-borne diseases, like chikungunya, yellow fever and malaria. An approximation of the cellular automata is proposed in terms of ordinary differential equations; the spreading of mosquitoes is studied and the influence of some model parameters are analyzed with numerical simulations. Finally, a method to combat dengue spreading is simulated based on a reduction of mosquito birth and mosquito bites in population.

Shift Work and Obesity among Canadian Women: A Cross-Sectional Study Using a Novel Exposure Assessment Tool

PubMed Central

McGlynn, Natalie; Kirsh, Victoria A.; Cotterchio, Michelle; Harris, M. Anne; Nadalin, Victoria; Kreiger, Nancy

2015-01-01

Background/Objectives It has been suggested that the association between shift work and chronic disease is mediated by an increase in obesity. However, investigations of the relationship between shift work and obesity reveal mixed findings. Using a recently developed exposure assessment tool, this study examined the association between shift work and obesity among Canadian women from two studies: a cohort of university alumni, and a population-based study. Methods Self-administered questionnaire data were used from healthy, currently employed females in a population-based study, the Ontario Women’s Diet and Health case-control study (n = 1611 controls), and from a subset of a of university alumni from the Canadian Study of Diet, Lifestyle, and Health (n = 1097) cohort study. Overweight was defined as BMI≥25 to <30, and obesity as BMI≥30. Reported occupation was converted to occupational codes and linked to a probability of shift work value derived from Survey of Labour and Income Dynamics data. Regular evenings, nights, or rotating work comprised shift work. Polytomous logistic regression estimated the association between probability of shift work, categorized as near nil, low, medium, and high probability of shift work, on overweight and obesity, controlling for detected confounders. Results In the population-based sample, high probability of shift work was associated with obesity (reference = near nil probability of shift work, OR: 1.88, 95% CI: 1.01–3.51, p = 0.047). In the alumni cohort, no significant association was detected between shift work and overweight or obesity. Conclusions As these analyses found a positive association between high probability of shift work exposure and obesity in a population-based sample, but not in an alumni cohort, it is suggested that the relationship between shift work and obesity is complex, and may be particularly susceptible to occupational and education-related factors within a given population. PMID:26376050

Shift Work and Obesity among Canadian Women: A Cross-Sectional Study Using a Novel Exposure Assessment Tool.

PubMed

McGlynn, Natalie; Kirsh, Victoria A; Cotterchio, Michelle; Harris, M Anne; Nadalin, Victoria; Kreiger, Nancy

2015-01-01

It has been suggested that the association between shift work and chronic disease is mediated by an increase in obesity. However, investigations of the relationship between shift work and obesity reveal mixed findings. Using a recently developed exposure assessment tool, this study examined the association between shift work and obesity among Canadian women from two studies: a cohort of university alumni, and a population-based study. Self-administered questionnaire data were used from healthy, currently employed females in a population-based study, the Ontario Women's Diet and Health case-control study (n = 1611 controls), and from a subset of a of university alumni from the Canadian Study of Diet, Lifestyle, and Health (n = 1097) cohort study. Overweight was defined as BMI≥25 to <30, and obesity as BMI≥30. Reported occupation was converted to occupational codes and linked to a probability of shift work value derived from Survey of Labour and Income Dynamics data. Regular evenings, nights, or rotating work comprised shift work. Polytomous logistic regression estimated the association between probability of shift work, categorized as near nil, low, medium, and high probability of shift work, on overweight and obesity, controlling for detected confounders. In the population-based sample, high probability of shift work was associated with obesity (reference = near nil probability of shift work, OR: 1.88, 95% CI: 1.01-3.51, p = 0.047). In the alumni cohort, no significant association was detected between shift work and overweight or obesity. As these analyses found a positive association between high probability of shift work exposure and obesity in a population-based sample, but not in an alumni cohort, it is suggested that the relationship between shift work and obesity is complex, and may be particularly susceptible to occupational and education-related factors within a given population.

New insights into the correlation structure of DSM-IV depression symptoms in the general population v. subsamples of depressed individuals.

PubMed

Foster, S; Mohler-Kuo, M

2018-06-01

Previous research failed to uncover a replicable dimensional structure underlying the symptoms of depression. We aimed to examine two neglected methodological issues in this research: (a) adjusting symptom correlations for overall depression severity; and (b) analysing general population samples v. subsamples of currently depressed individuals. Using population-based cross-sectional and longitudinal data from two nations (Switzerland, 5883 young men; USA, 2174 young men and 2244 young women) we assessed the dimensions of the nine DSM-IV depression symptoms in young adults. In each general-population sample and each subsample of currently depressed participants, we conducted a standardised process of three analytical steps, based on exploratory and confirmatory factor and bifactor analysis, to reveal any replicable dimensional structure underlying symptom correlations while controlling for overall depression severity. We found no evidence of a replicable dimensional structure across samples when adjusting symptom correlations for overall depression severity. In the general-population samples, symptoms correlated strongly and a single dimension of depression severity was revealed. Among depressed participants, symptom correlations were surprisingly weak and no replicable dimensions were identified, regardless of severity-adjustment. First, caution is warranted when considering studies assessing dimensions of depression because general population-based studies and studies of depressed individuals generate different data that can lead to different conclusions. This problem likely generalises to other models based on the symptoms' inter-relationships such as network models. Second, whereas the overall severity aligns individuals on a continuum of disorder intensity that allows non-affected individuals to be distinguished from affected individuals, the clinical evaluation and treatment of depressed individuals should focus directly on each individual's symptom profile.

ASSESSMENT OF THE FOOD PATTERNS OF IMMIGRANT ECUADORIAN POPULATION IN SOUTHERN SPAIN BASED ON A 24-H FOOD RECALL SURVEY.

PubMed

Neira-Mosquera, Juan Alejandro; Sanchez-Llaguno, Sungey; Pérez-Rodríguez, Fernando; Moreno-Rojas, Rafael

2015-08-01

Ecuador is a country with limited nutritional information, with exception of some general studies supported by Food Agriculture Organization (FAO) Aims: to carry out a nutritional assessment of the diet of Ecuadorian immigrant population in Southern Spain to determine differences in food patterns and possible nutritional deficiencies. the nutritional assessment was based on a 24-h food recall survey applied to the Ecuadorian population residing in Seville and Córdoba (Spain) in combination with the application of national and international food composition data bases. Nutrient intake levels and fulfillment of Dietary Reference Intakes (DRIs) were estimated and statistically tested for social, sex, age and geographical factors. macronutrient distributions and nutrient intake levels in relation with DRIs were adequate in most cases. Importantly, Ecuadorian food habits were still present in immigrant population, with rice being the main energy source. Intakes levels were significantly different for several nutrients depending on age group, sex, place of residence and professional occupation. Comparison with previous nutritional data from Ecuador revealed a better nutritional status of immigrant population in Spain, though deficiencies in fiber, vitamin E, I and Se were detected in the diet of both populations. Nevertheless, data for these deficiencies were insufficient to be conclusive given both limitations in the food composition data bases (e.g. Se) and the lack of more adequate information tools for its assessment (e.g. long-term studies for vitamin E). the results in the present study evidenced that Ecuadorian immigrants in Spain showed more adequate food patterns that those reported for Ecuador. These data can be helpful to get further insight into the nutritional value of Ecuadorian diet and develop suitable nutrition intervention. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Associations of all-cause mortality with census-based neighbourhood deprivation and population density in Japan: a multilevel survival analysis.

PubMed

Nakaya, Tomoki; Honjo, Kaori; Hanibuchi, Tomoya; Ikeda, Ai; Iso, Hiroyasu; Inoue, Manami; Sawada, Norie; Tsugane, Shoichiro

2014-01-01

Despite evidence that neighbourhood conditions affect residents' health, no prospective studies of the association between neighbourhood socio-demographic factors and all-cause mortality have been conducted in non-Western societies. Thus, we examined the effects of areal deprivation and population density on all-cause mortality in Japan. We employed census and survival data from the Japan Public Health Center-based Prospective Study, Cohort I (n = 37,455), consisting of middle-aged residents (40 to 59 years at the baseline in 1990) living in four public health centre districts. Data spanned between 1990 and 2010. A multilevel parametric proportional-hazard regression model was applied to estimate the hazard ratios (HRs) of all-cause mortality by two census-based areal variables--areal deprivation index and population density--as well as individualistic variables such as socioeconomic status and various risk factors. We found that areal deprivation and population density had moderate associations with all-cause mortality at the neighbourhood level based on the survival data with 21 years of follow-ups. Even when controlling for individualistic socio-economic status and behavioural factors, the HRs of the two areal factors (using quartile categorical variables) significantly predicted mortality. Further, this analysis indicated an interaction effect of the two factors: areal deprivation prominently affects the health of residents in neighbourhoods with high population density. We confirmed that neighbourhood socio-demographic factors are significant predictors of all-cause death in Japanese non-metropolitan settings. Although further study is needed to clarify the cause-effect relationship of this association, the present findings suggest that health promotion policies should consider health disparities between neighbourhoods and possibly direct interventions towards reducing mortality in densely populated and highly deprived neighbourhoods.

Trends and predictors of outcomes after surgery for hepatocellular carcinoma: A nationwide population-based study in Taiwan.

PubMed

Chiu, C-C; Wang, J-J; Chen, Y-S; Chen, J-J; Tsai, T-C; Lai, C-C; Sun, D-P; Shi, H-Y

2015-09-01

Despite the huge and growing global burden of hepatocellular carcinoma (HCC), high-quality population-based studies of HCC prevalence and outcomes are scarce. To analyze trends and predictors of hospital resource utilization and mortality rates in a population of patients who had received HCC surgery. This population-based patient cohort study retrospectively analyzed 23,107 patients who had received surgical treatment for HCC from 1998 to 2009. The prevalence rate of surgical treatment in HCC patients significantly increased by 167.4% from 4.857 per 100,000 persons in 1998 to 12.989 per 100,000 persons in 2009 (P < 0.001). Age, gender, Deyo-Charlson co-morbidity index score, hospital volume, surgeon volume, digestive system disease, hepatitis type and liver cirrhosis were significantly associated with HCC surgical outcomes (P < 0.05). Over the 12-year period analyzed, the estimated mean hospital treatment cost increased 9.4% whereas mean length of stay (LOS) decreased 25.3%. The estimated mean overall survival time after HCC surgery was 40.9 months (SD 1.2 months), and the overall in-hospital 1-, 3-, and 5-year survival rates were 97.2%, 79.9%, 61.1%, and 54.6%, respectively. These population-based data reveal that the prevalence of HCC has increased, especially in older patients. Additionally, hospital treatment costs for HCC have increased despite decreases in LOS. These analytical results should be applicable to most countries with relatively small populations. Additionally, healthcare providers and patients should recognize that attributes of both the patient and the hospital may affect outcomes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Associations of All-Cause Mortality with Census-Based Neighbourhood Deprivation and Population Density in Japan: A Multilevel Survival Analysis

PubMed Central

Nakaya, Tomoki; Honjo, Kaori; Hanibuchi, Tomoya; Ikeda, Ai; Iso, Hiroyasu; Inoue, Manami; Sawada, Norie; Tsugane, Shoichiro

2014-01-01

Background Despite evidence that neighbourhood conditions affect residents' health, no prospective studies of the association between neighbourhood socio-demographic factors and all-cause mortality have been conducted in non-Western societies. Thus, we examined the effects of areal deprivation and population density on all-cause mortality in Japan. Methods We employed census and survival data from the Japan Public Health Center-based Prospective Study, Cohort I (n = 37,455), consisting of middle-aged residents (40 to 59 years at the baseline in 1990) living in four public health centre districts. Data spanned between 1990 and 2010. A multilevel parametric proportional-hazard regression model was applied to estimate the hazard ratios (HRs) of all-cause mortality by two census-based areal variables —areal deprivation index and population density—as well as individualistic variables such as socioeconomic status and various risk factors. Results We found that areal deprivation and population density had moderate associations with all-cause mortality at the neighbourhood level based on the survival data with 21 years of follow-ups. Even when controlling for individualistic socio-economic status and behavioural factors, the HRs of the two areal factors (using quartile categorical variables) significantly predicted mortality. Further, this analysis indicated an interaction effect of the two factors: areal deprivation prominently affects the health of residents in neighbourhoods with high population density. Conclusions We confirmed that neighbourhood socio-demographic factors are significant predictors of all-cause death in Japanese non-metropolitan settings. Although further study is needed to clarify the cause-effect relationship of this association, the present findings suggest that health promotion policies should consider health disparities between neighbourhoods and possibly direct interventions towards reducing mortality in densely populated and highly deprived neighbourhoods. PMID:24905731

The role of self-defined race/ethnicity in population structure control.

PubMed

Liu, X-Q; Paterson, A D; John, E M; Knight, J A

2006-07-01

Population-based association studies are powerful tools for the genetic mapping of complex diseases. However, this method is sensitive to potential confounding by population structure. While statistical methods that use genetic markers to detect and control for population structure have been the focus of current literature, the utility of self-defined race/ethnicity in controlling for population structure has been controversial. In this study of 1334 individuals, who self-identified as either African American, European American or Hispanic, we demonstrated that when the true underlying genetic structure and the self-defined racial/ethnic groups were roughly in agreement with each other, the self-defined race/ethnicity information was useful in the control of population structure.

Qualifications and Competencies for Population Health Management Positions: A Content Analysis of Job Postings.

PubMed

Meyer, Melanie

2017-12-01

The need for population health management expertise has increased as the health care industry shifts toward value-based care. However, many organizations report hiring gaps as they seek to fill positions. The purpose of this study was to analyze the types of population health management positions for which health care organizations are hiring, including qualifications and competencies required for these positions. A content analysis was conducted on 271 job postings collected during a 2-month period. A typology of qualifications and competencies was developed based on the content analysis. Profiles were generated for the top 5 job title classifications: directors, coordinators, care managers, analysts, and specialists. This study highlights the investment health care organizations are making in population health management and the prominent role these positions are playing in the health care environment today. Many organizations are building out population health management teams resulting in multiple positions at different levels being added. As the market demands competent candidates who are equipped with specialized population health expertise as well as practical experience in program development, technology applications, care management, and analytics, professional education programs will need to adapt curricula to address the required areas. Competencies for specific job title classifications may need further evaluation and refinement over time. Study results can be used by organizations for strategic planning, by educators to target needed qualifications and competencies, and by researchers and policy advisors to assess progress toward value-based care.

Importance of latrine communication in European rabbits shifts along a rural-to-urban gradient.

PubMed

Ziege, Madlen; Bierbach, David; Bischoff, Svenja; Brandt, Anna-Lena; Brix, Mareike; Greshake, Bastian; Merker, Stefan; Wenninger, Sandra; Wronski, Torsten; Plath, Martin

2016-06-14

Information transfer in mammalian communication networks is often based on the deposition of excreta in latrines. Depending on the intended receiver(s), latrines are either formed at territorial boundaries (between-group communication) or in core areas of home ranges (within-group communication). The relative importance of both types of marking behavior should depend, amongst other factors, on population densities and social group sizes, which tend to differ between urban and rural wildlife populations. Our study is the first to assess (direct and indirect) anthropogenic influences on mammalian latrine-based communication networks along a rural-to-urban gradient in European rabbits (Oryctolagus cuniculus) living in urban, suburban and rural areas in and around Frankfurt am Main (Germany). The proportion of latrines located in close proximity to the burrow was higher at rural study sites compared to urban and suburban ones. At rural sites, we found the largest latrines and highest latrine densities close to the burrow, suggesting that core marking prevailed. By contrast, latrine dimensions and densities increased with increasing distance from the burrow in urban and suburban populations, suggesting a higher importance of peripheral marking. Increased population densities, but smaller social group sizes in urban rabbit populations may lead to an increased importance of between-group communication and thus, favor peripheral over core marking. Our study provides novel insights into the manifold ways by which man-made habitat alterations along a rural-to-urban gradient directly and indirectly affect wildlife populations, including latrine-based communication networks.

The risk-stratified osteoporosis strategy evaluation study (ROSE): a randomized prospective population-based study. Design and baseline characteristics.

PubMed

Rubin, Katrine Hass; Holmberg, Teresa; Rothmann, Mette Juel; Høiberg, Mikkel; Barkmann, Reinhard; Gram, Jeppe; Hermann, Anne Pernille; Bech, Mickael; Rasmussen, Ole; Glüer, Claus C; Brixen, Kim

2015-02-01

The risk-stratified osteoporosis strategy evaluation study (ROSE) is a randomized prospective population-based study investigating the effectiveness of a two-step screening program for osteoporosis in women. This paper reports the study design and baseline characteristics of the study population. 35,000 women aged 65-80 years were selected at random from the population in the Region of Southern Denmark and-before inclusion-randomized to either a screening group or a control group. As first step, a self-administered questionnaire regarding risk factors for osteoporosis based on FRAX(®) was issued to both groups. As second step, subjects in the screening group with a 10-year probability of major osteoporotic fractures ≥15% were offered a DXA scan. Patients diagnosed with osteoporosis from the DXA scan were advised to see their GP and discuss pharmaceutical treatment according to Danish National guidelines. The primary outcome is incident clinical fractures as evaluated through annual follow-up using the Danish National Patient Registry. The secondary outcomes are cost-effectiveness, participation rate, and patient preferences. 20,904 (60%) women participated and included in the baseline analyses (10,411 in screening and 10,949 in control group). The mean age was 71 years. As expected by randomization, the screening and control groups had similar baseline characteristics. Screening for osteoporosis is at present not evidence based according to the WHO screening criteria. The ROSE study is expected to provide knowledge of the effectiveness of a screening strategy that may be implemented in health care systems to prevent fractures.

A population-based job exposure matrix for power-frequency magnetic fields.

PubMed

Bowman, Joseph D; Touchstone, Jennifer A; Yost, Michael G

2007-09-01

A population-based job exposure matrix (JEM) was developed to assess personal exposures to power-frequency magnetic fields (MF) for epidemiologic studies. The JEM compiled 2,317 MF measurements taken on or near workers by 10 studies in the United States, Sweden, New Zealand, Finland, and Italy. A database was assembled from the original data for six studies plus summary statistics grouped by occupation from four other published studies. The job descriptions were coded into the 1980 Standard Occupational Classification system (SOC) and then translated to the 1980 job categories of the U.S. Bureau of the Census (BOC). For each job category, the JEM database calculated the arithmetic mean, standard deviation, geometric mean, and geometric standard deviation of the workday-average MF magnitude from the combined data. Analysis of variance demonstrated that the combining of MF data from the different sources was justified, and that the homogeneity of MF exposures in the SOC occupations was comparable to JEMs for solvents and particulates. BOC occupation accounted for 30% of the MF variance (p < 10(-6)), and the contrast (ratio of the between-job variance to the total of within- and between-job variances) was 88%. Jobs lacking data had their exposures inferred from measurements on similar occupations. The JEM provided MF exposures for 97% of the person-months in a population-based case-control study and 95% of the jobs on death certificates in a registry study covering 22 states. Therefore, we expect this JEM to be useful in other population-based epidemiologic studies.

Prevalence of self-reported stomach symptoms after consuming milk among indigenous Sami and non-Sami in Northern- and Mid-Norway - the SAMINOR study.

PubMed

Hansen, Ketil Lenert; Brustad, Magritt; Johnsen, Knut

2015-01-01

The main purpose of this work was to identify the prevalence of self-reported stomach symptoms after consuming milk among Sami and non-Sami adults. A cross-sectional population-based study (the SAMINOR study). Data were collected by self-administrated questionnaires. SAMINOR is a population-based study of health and living conditions conducted in 24 municipalities in Northern Norway during 2003 and 2004. The present study included 15,546 individuals aged between 36 and 79, whose ethnicity was categorized as Sami (33.4%), Kven (7.3%) and Norwegian majority population (57.2%). Sami respondents had a higher prevalence of self-reported stomach symptoms after consuming milk than the Norwegian majority population. The reporting was highest among Sami females (27.1%). Consumption of milk and dairy products (yoghurt and cheese) was high among all the ethnic groups. However, significantly more Sami than non-Sami never (or rarely) consume milk or cheese, and individuals who reported stomach symptoms after consuming milk had an significant lower intake of dairy products than those not reporting stomach symptoms after consuming dairy products. Sami reported general abdominal pain more often than the majority population. The adjusted models show a significant effect of Sami ethnicity in both men and women on self-reported stomach symptoms after consuming milk. In females, the odds ratio (OR)=1.77 (p=0.001) and in males OR=1.64 (p=0.001). Our study shows that the Sami population reported more stomach symptoms after consuming milk, suggesting a higher prevalence of milk intolerance among the Sami population than the Norwegian majority population.

Maternal and perinatal mortality by place of delivery in sub-Saharan Africa: a meta-analysis of population-based cohort studies.

PubMed

Chinkhumba, Jobiba; De Allegri, Manuela; Muula, Adamson S; Robberstad, Bjarne

2014-09-28

Facility-based delivery has gained traction as a key strategy for reducing maternal and perinatal mortality in developing countries. However, robust evidence of impact of place of delivery on maternal and perinatal mortality is lacking. We aimed to estimate the risk of maternal and perinatal mortality by place of delivery in sub-Saharan Africa. We conducted a systematic review of population-based cohort studies reporting on risk of maternal or perinatal mortality at the individual level by place of delivery in sub-Saharan Africa. Newcastle-Ottawa Scale was used to assess study quality. Outcomes were summarized in pooled analyses using fixed and random effects models. We calculated attributable risk percentage reduction in mortality to estimate exposure effect. We report mortality ratios, crude odds ratios and associated 95% confidence intervals. We found 9 population-based cohort studies: 6 reporting on perinatal and 3 on maternal mortality. The mean study quality score was 10 out of 15 points. Control for confounders varied between the studies. A total of 36,772 pregnancy episodes were included in the analyses. Overall, perinatal mortality is 21% higher for home compared to facility-based deliveries, but the difference is only significant when produced with a fixed effects model (OR 1.21, 95% CI: 1.02-1.46) and not when produced by a random effects model (OR 1.21, 95% CI: 0.79-1.84). Under best settings, up to 14 perinatal deaths might be averted per 1000 births if the women delivered at facilities instead of homes. We found significantly increased risk of maternal mortality for facility-based compared to home deliveries (OR 2.29, 95% CI: 1.58-3.31), precluding estimates of attributable risk fraction. Evaluating the impact of facility-based delivery strategy on maternal and perinatal mortality using population-based studies is complicated by selection bias and poor control of confounders. Studies that pool data at an individual level may overcome some of these problems and provide better estimates of relative effectiveness of place of delivery in the region.

Study of Genetic Diversity among Simmental Cross Cattle in West Sumatra Based on Microsatellite Markers

PubMed Central

Agung, Paskah Partogi; Saputra, Ferdy; Septian, Wike Andre; Lusiana; Zein, Moch. Syamsul Arifin; Sulandari, Sri; Anwar, Saiful; Wulandari, Ari Sulistyo; Said, Syahruddin; Tappa, Baharuddin

2016-01-01

A study was conducted to assess the genetic diversity among Simmental Cross cattle in West Sumatra using microsatellite DNA markers. A total of 176 individual cattle blood samples was used for obtaining DNA samples. Twelve primers of microsatellite loci as recommended by FAO were used to identify the genetic diversity of the Simmental Cross cattle population. Multiplex DNA fragment analysis method was used for allele identification. All the microsatellite loci in this study were highly polymorphic and all of the identified alleles were able to classify the cattle population into several groups based on their genetic distance. The heterozygosity values of microsatellite loci in this study ranged from 0.556 to 0.782. The polymorphism information content (PIC) value of the 12 observed loci is high (PIC>0.5). The highest PIC value in the Simmental cattle population was 0.893 (locus TGLA53), while the lowest value was 0.529 (locus BM1818). Based on the genetic distance value, the subpopulation of the Simmental Cross-Agam and the Simmental Cross-Limapuluh Kota was exceptionally close to the Simmental Purebred thus indicating that a grading-up process has taken place with the Simmental Purebred. In view of the advantages possessed by the Simmental Cross cattle and the evaluation of the genetic diversity results, a number of subpopulations in this study can be considered as the initial (base) population for the Simmental Cross cattle breeding programs in West Sumatra, Indonesia. PMID:26732442

Spatial capture-recapture models for jointly estimating population density and landscape connectivity

USGS Publications Warehouse

Royle, J. Andrew; Chandler, Richard B.; Gazenski, Kimberly D.; Graves, Tabitha A.

2013-01-01

Population size and landscape connectivity are key determinants of population viability, yet no methods exist for simultaneously estimating density and connectivity parameters. Recently developed spatial capture–recapture (SCR) models provide a framework for estimating density of animal populations but thus far have not been used to study connectivity. Rather, all applications of SCR models have used encounter probability models based on the Euclidean distance between traps and animal activity centers, which implies that home ranges are stationary, symmetric, and unaffected by landscape structure. In this paper we devise encounter probability models based on “ecological distance,” i.e., the least-cost path between traps and activity centers, which is a function of both Euclidean distance and animal movement behavior in resistant landscapes. We integrate least-cost path models into a likelihood-based estimation scheme for spatial capture–recapture models in order to estimate population density and parameters of the least-cost encounter probability model. Therefore, it is possible to make explicit inferences about animal density, distribution, and landscape connectivity as it relates to animal movement from standard capture–recapture data. Furthermore, a simulation study demonstrated that ignoring landscape connectivity can result in negatively biased density estimators under the naive SCR model.

Spatial capture--recapture models for jointly estimating population density and landscape connectivity.

PubMed

Royle, J Andrew; Chandler, Richard B; Gazenski, Kimberly D; Graves, Tabitha A

2013-02-01

Population size and landscape connectivity are key determinants of population viability, yet no methods exist for simultaneously estimating density and connectivity parameters. Recently developed spatial capture--recapture (SCR) models provide a framework for estimating density of animal populations but thus far have not been used to study connectivity. Rather, all applications of SCR models have used encounter probability models based on the Euclidean distance between traps and animal activity centers, which implies that home ranges are stationary, symmetric, and unaffected by landscape structure. In this paper we devise encounter probability models based on "ecological distance," i.e., the least-cost path between traps and activity centers, which is a function of both Euclidean distance and animal movement behavior in resistant landscapes. We integrate least-cost path models into a likelihood-based estimation scheme for spatial capture-recapture models in order to estimate population density and parameters of the least-cost encounter probability model. Therefore, it is possible to make explicit inferences about animal density, distribution, and landscape connectivity as it relates to animal movement from standard capture-recapture data. Furthermore, a simulation study demonstrated that ignoring landscape connectivity can result in negatively biased density estimators under the naive SCR model.

Measuring Stress Before and During Pregnancy: A Review of Population-Based Studies of Obstetric Outcomes

PubMed Central

Witt, Whitney; Litzelman, Kristin; Cheng, Erika R; Wakeel, Fathima; Barker, Emily S.

2013-01-01

Objectives Mounting evidence from clinic and convenience samples suggests that stress is an important predictor of adverse obstetric outcomes. Using a proposed theoretical framework, this review identified and synthesized the population-based literature on the measurement of stress prior to and during pregnancy in relation to obstetric outcomes. Methods Population-based, peer-reviewed empirical articles that examined stress prior to or during pregnancy in relation to obstetric outcomes were identified in the PubMed and PsycInfo databases. Articles were evaluated to determine the domain(s) of stress (environmental, psychological, and/or biological), period(s) of stress (preconception and/or pregnancy), and strength of the association between stress and obstetric outcomes. Results Thirteen studies were evaluated. The identified studies were all conducted in developed countries. The majority of studies examined stress only during pregnancy (n=10); three examined stress during both the preconception and pregnancy periods (n=3). Most studies examined the environmental domain (e.g., life events) only (n=9), two studies examined the psychological domain only, and two studies examined both. No study incorporated a biological measure of stress. Environmental stressors before and during pregnancy were associated with worse obstetric outcomes, although some conflicting findings exist. Conclusions Few population-based studies have examined stress before or during pregnancy in relation to obstetric outcomes. Although considerable variation exists in the measurement of stress across studies, environmental stress increased the risk for poor obstetric outcomes. Additional work using a lifecourse approach is needed to fill the existing gaps in the literature and to develop a more comprehensive understanding of the mechanisms by which stress impacts obstetric outcomes. PMID:23447085

Systematic Review of the Use of Online Questionnaires among the Geriatric Population

PubMed Central

Remillard, Meegan L.; Mazor, Kathleen M.; Cutrona, Sarah L.; Gurwitz, Jerry H.; Tjia, Jennifer

2014-01-01

Background/Objectives The use of internet-based questionnaires to collect information from older adults is not well established. This systematic literature review of studies using online questionnaires in older adult populations aims to 1. describe methodologic approaches to population targeting and sampling and 2. summarize limitations of Internet-based questionnaires in geriatric populations. Design, Setting, Participants We identified English language articles using search terms for geriatric, age 65 and over, Internet survey, online survey, Internet questionnaire, and online questionnaire in PubMed and EBSCO host between 1984 and July 2012. Inclusion criteria were: study population mean age ≥65 years old and use of an online questionnaire for research. Review of 336 abstracts yielded 14 articles for full review by 2 investigators; 11 articles met inclusion criteria. Measurements Articles were extracted for study design and setting, patient characteristics, recruitment strategy, country, and study limitations. Results Eleven (11) articles were published after 2001. Studies had populations with a mean age of 65 to 78 years, included descriptive and analytical designs, and were conducted in the United States, Australia, and Japan. Recruiting methods varied widely from paper fliers and personal emails to use of consumer marketing panels. Investigator-reported study limitations included the use of small convenience samples and limited generalizability. Conclusion Online questionnaires are a feasible method of surveying older adults in some geographic regions and for some subsets of older adults, but limited Internet access constrains recruiting methods and often limits study generalizability. PMID:24635138

Genotyping faecal samples of Bengal tiger Panthera tigris tigris for population estimation: a pilot study.

PubMed

Bhagavatula, Jyotsna; Singh, Lalji

2006-10-17

Bengal tiger Panthera tigris tigris the National Animal of India, is an endangered species. Estimating populations for such species is the main objective for designing conservation measures and for evaluating those that are already in place. Due to the tiger's cryptic and secretive behaviour, it is not possible to enumerate and monitor its populations through direct observations; instead indirect methods have always been used for studying tigers in the wild. DNA methods based on non-invasive sampling have not been attempted so far for tiger population studies in India. We describe here a pilot study using DNA extracted from faecal samples of tigers for the purpose of population estimation. In this study, PCR primers were developed based on tiger-specific variations in the mitochondrial cytochrome b for reliably identifying tiger faecal samples from those of sympatric carnivores. Microsatellite markers were developed for the identification of individual tigers with a sibling Probability of Identity of 0.005 that can distinguish even closely related individuals with 99.9% certainty. The effectiveness of using field-collected tiger faecal samples for DNA analysis was evaluated by sampling, identification and subsequently genotyping samples from two protected areas in southern India. Our results demonstrate the feasibility of using tiger faecal matter as a potential source of DNA for population estimation of tigers in protected areas in India in addition to the methods currently in use.

Conservation genetics of the rare Pyreneo-Cantabrian endemic Aster pyrenaeus (Asteraceae)

PubMed Central

Escaravage, Nathalie; Cambecèdes, Jocelyne; Largier, Gérard; Pornon, André

2011-01-01

Background and aims Aster pyrenaeus (Asteraceae) is an endangered species, endemic to the Pyrenees and Cantabrian Mountain ranges (Spain). For its long-term persistence, this taxon needs an appropriate conservation strategy to be implemented. In this context, we studied the genetic structure over the entire geographical range of the species and then inferred the genetic relationships between populations. Methodology Molecular diversity was analysed for 290 individuals from 12 populations in the Pyrenees and the Cantabrian Mountains using inter simple sequence repeats (ISSRs). Bayesian-based analysis was applied to examine population structure. Principal results Analysis of genetic similarity and diversity, based on 87 polymorphic ISSR markers, suggests that despite being small and isolated, populations have an intermediate genetic diversity level (P % = 52.8 %, HE = 0.21 ± 0.01, genetic similarity between individuals = 49.6 %). Genetic variation was mainly found within populations (80–84 %), independently of mountain ranges, whereas 16–18 % was found between populations and <5 % between mountain ranges. Analyses of molecular variance indicated that population differentiation was highly significant. However, no significant correlation was found between the genetic and geographical distances among populations (Rs = 0.359, P = 0.140). Geographical structure based on assignment tests identified five different gene pools that were independent of any particular structure in the landscape. Conclusions The results suggest that population isolation is probably relatively recent, and that the outbreeding behaviour of the species maintains a high within-population genetic diversity. We assume that some long-distance dispersal, even among topographically remote populations, may be determinant for the pattern of genetic variation found in populations. Based on these findings, strategies are proposed for genetic conservation and management of the species. PMID:22476499

Effectiveness of music-based interventions on motricity or cognitive functioning in neurological populations: a systematic review.

PubMed

Moumdjian, Lousin; Sarkamo, Teppo; Leone, Carmela; Leman, Marc; Feys, Peter

2017-06-01

Motor and cognitive symptoms are frequent in persons with neurological disorders and often require extensive long-term rehabilitation. Recently, a variety of music-based interventions have been introduced into neurological rehabilitation as training tools. This review aims to 1) describe and define music-based intervention modalities and content which are applied in experimental studies; and 2) describe the effects of these interventions on motor and/or cognitive symptoms in the neurological population. The databases PubMed and Web of Science were searched. Cited references of included articles where screened for potential inclusion. A systematic literature search up to 20th of June 2016 was conducted to include controlled trials and cohort studies that have used music-based interventions for ≥3 weeks in the neurological population (in- and outpatients) targeting motor and/or cognitive symptoms. No limitations to publication date was set. EVIDENCE SYNTHESISː Nineteen articles comprising thirteen randomized controlled trials (total participants Nexp=241, Nctrl=269), four controlled trials (Nexp=59, Nctrl=53) and two cohort studies (N.=27) were included. Fourteen studies were conducted in stroke, three in Parkinson's disease, and two in multiple sclerosis population. Modalities of music-based interventions were clustered into four groups: instrument-based, listening-based, rhythm-based, and multicomponent-based music interventions. Overall, studies consistently showed that music-based interventions had similar or larger effects than conventional rehabilitation on upper limb function (N.=16; fine motricity, hand and arm capacity, finger and hand tapping velocity/variability), mobility (N.=7; gait parameters), and cognition (N.=4; verbal memory and focused attention). CONCLUSIONSː Variety of modalities using music-based interventions has been identified and grouped into four clusters. Effects of interventions demonstrate an improvement in the domains assessed. Evidence is most available for improving motricity in stroke. More studies are warranted to investigate cognition as well as motor and cognition dysfunctions in combination. Instrument-based music interventions can improve fine motor dexterity and gross motor functions in stroke. Rhythm-based music interventions can improve gait parameters of velocity and cadence in stroke, Parkinson's disease and multiple sclerosis. Cognition in the domains of verbal memory and focused attention can improve after listening-based music interventions in stroke.

The Ottawa Citizen Engagement and Action Model (OCEAM): A Citizen engagement Strategy Operationalized Through The Participatory Research in Ottawa, Management and Point-of-care of Tobacco (PROMPT) Study: A Community Based Participatory Action Research Project in Inner City Ottawa.

PubMed

Pakhale, Smita; Kaur, Tina; Florence, Kelly; Rose, Tiffany; Boyd, Robert; Haddad, Joanne; Pettey, Donna; Muckle, Wendy; Tyndall, Mark

2016-01-01

The PROMPT study is a community-based research project designed to understand the factors which affect smoking as well as ways to manage, reduce and quit smoking among people who use drugs in Ottawa. There is strong medical evidence that smoking tobacco is related to more than two dozen diseases and conditions. Smoking tobacco remains the leading cause of preventable death and has negative health impacts on people of all ages. Although Ottawa has one of the lowest smoking rates in Ontario (12 %), major differences exist, with approximately a 96 % smoking rate among those who use drugs in the city of Ottawa. To address this inequity, we recruited and trained four community research peers who were representative of the study target population (ex- or currently homeless, insecurely housed or multi-drug users). We designed the ten-step Ottawa Citizen Engagement and Action Model (OCEAM) for the PROMPT study. In this paper we have described this process in a step-by-step fashion, as used in the PROMPT study. The eighty PROMPT participants are being followed for six months and are being provided with free and off-label Nicotine Replacement Therapy (NRT). Objectives The PROMPT study, Participatory Research in Ottawa, Management and Point-of-care of Tobacco, is a prospective cohort study which utilizes community-based participation and social network-based approaches to address tobacco dependence in inner city Ottawa. The project was designed to: facilitate retention of participants; to understand the barriers and facilitators of smoking; optimize ways to manage, reduce, and quit tobacco use among people who use drugs in Ottawa, Canada. The purpose of this paper is to describe the processes utilized in citizen or patient engagement in academic research, through our tobacco dependence management project in the inner city population in Ottawa, Canada. Background Tobacco smoking is inequitably distributed in Canada with rates at 12 % in Ottawa, as compared to 18 % in rest of Canada. However, the PROUD Study (Participatory Research in Ottawa: Understanding Drugs) demonstrated that 96 % of the inner city population, of Ottawa currently smoke tobacco. This distinct inequity in tobacco use translates into inequitable distribution of health outcomes, such morbidity and mortality in this population. Consequently, a community-based participatory, peer-led research project was conducted in the inner city population of Ottawa. Methods We recruited and trained four community research peers who were representative of the study target population. We conceived, designed and operationalized the ten-step Ottawa Citizen Engagement and Action Model (OCEAM) for the PROMPT study. The peers have co-led all aspects of the project from conceptualizing the study question to participating in knowledge translation. Each step of the project had defined objectives and outcome measures. Discussion The involvement of peers in recruitment ensured representation of tobacco and drug users-individuals truly representative of the intended target population. Peer, participant engagement and trust was established from the conception of the project. For historical and self-evident reasons, trust and engagement is rarely found in this population. Peers successfully participated in all ten steps of the Citizen Engagement and Action model. The PROMPT study utilized the CBPR (Community Based Participatory research) approach to encourage engagement and build trust in a difficult to reach and hard to treat, inner city population. The ten-step OCEAM model was conceived, designed and operationalized and the PROMPT study will continue to follow the eighty PROMPT participants for six months to understand the optimal ways to manage, reduce, and quit smoking within an inner city population.

Epigenetic differentiation and relationship to adaptive genetic divergence in discrete populations of the violet Viola cazorlensis.

PubMed

Herrera, Carlos M; Bazaga, Pilar

2010-08-01

*In plants, epigenetic variations based on DNA methylation are often heritable and could influence the course of evolution. Before this hypothesis can be assessed, fundamental questions about epigenetic variation remain to be addressed in a real-world context, including its magnitude, structuring within and among natural populations, and autonomy in relation to the genetic context. *Extent and patterns of cytosine methylation, and the relationship to adaptive genetic divergence between populations, were investigated for wild populations of the southern Spanish violet Viola cazorlensis (Violaceae) using the methylation-sensitive amplified polymorphism (MSAP) technique, a modification of the amplified fragment length polymorphism method (AFLP) based on the differential sensitivity of isoschizomeric restriction enzymes to site-specific cytosine methylation. *The genome of V. cazorlensis plants exhibited extensive levels of methylation, and methylation-based epigenetic variation was structured into distinct between- and within- population components. Epigenetic differentiation of populations was correlated with adaptive genetic divergence revealed by a Bayesian population-genomic analysis of AFLP data. Significant associations existed at the individual genome level between adaptive AFLP loci and the methylation state of methylation-susceptible MSAP loci. *Population-specific, divergent patterns of correlated selection on epigenetic and genetic individual variation could account for the coordinated epigenetic-genetic adaptive population differentiation revealed by this study.

Gender equality in university sportspeople's drinking.

PubMed

O'Brien, Kerry S; Hunter, Jackie; Kypri, Kypros; Ali, Ajmol

2008-11-01

In large population-based alcohol studies males are shown consistently to drink more, and more hazardously, than females. However, research from some countries suggests that gender differences in drinking are converging, with females drinking more than in the past. Large population-based research may miss gender-based changes in drinking behaviours that occur in sub-populations most at risk of hazardous drinking. We examine gender differences in a sub-population where hazardous drinking is common and endorsed, namely university sportspeople. The Alcohol Use Disorders Identification Test (AUDIT) and a drinking motives measure were used to assess hazardous drinking behaviours and drinking motives in 631 university sportspeople (females = 331, 52%). There were no gender differences in AUDIT scores. However, drinking motives differed between genders, with coping motives being a significant predictor of hazardous drinking in females but not males. Hazardous drinking, including binge drinking (46.3%) and frequent binge drinking (35%), in New Zealand university sportspeople is high for both males and females. New Zealand university sportspeople are one population where gender differences in drinking are not apparent and run counter to European population based research and research in US sporting populations. Gender role equality in the university systems, and endorsement of drinking in sporting culture, may account for the lack of gender differences in this New Zealand sporting population. Future research on gender differences in drinking should examine sub-populations where gender role differentiation is low, and socio-cultural/structural factors supporting gender equality are high.

Food risk assessment for perfluoroalkyl acids and brominated flame retardants in the French population: results from the second French total diet study.

PubMed

Rivière, G; Sirot, V; Tard, A; Jean, J; Marchand, P; Veyrand, B; Le Bizec, B; Leblanc, J C

2014-09-01

To determine the exposure of the French population to toxic compounds contaminating the food chain, a total diet study was performed in France between 2007 and 2009. This study was designed to reflect the consumption habits of the French population and covered the most important foods in terms of consumption, selected nutrients and contribution to contamination. Based on French consumption data, the present study reports the dietary exposure to perfluoroalkyl acids (16 congeners) and brominated flame retardants (polybrominated diphenyl ethers, hexabromocyclododecane and polybrominated biphenyls). Comparison of the calculated dietary exposures with the generally accepted health-based guidance values revealed that most compounds do not pose any risk. There are however knowledge gaps for some congeners in these large chemical classes. Copyright © 2014 Elsevier B.V. All rights reserved.

Epidemiology of cognitive aging and Alzheimer's disease: contributions of the cache county utah study of memory, health and aging.

PubMed

Hayden, Kathleen M; Welsh-Bohmer, Kathleen A

2012-01-01

Epidemiological studies of Alzheimer's disease (AD) provide insights into changing public health trends and their contribution to disease incidence. The current chapter considers how the population-based approach has contributed to our understanding of lifetime exposures that contribute to later disease risk and may act to modify onset of symptoms. We focus on the findings from a recent survey of an exceptionally long-lived population, the Cache County Utah Study of Memory, Health, and Aging. This study is confined to a single geographic population has allowed estimation of the genetic and environmental influences on AD expression across the expected human lifespan of 95+ years. Given the emphasis of this text on the behavioral neurosciences of aging, we highlight within the current chapter the particular contributions of this population-based study to the neuropsychology of aging and AD. We also discuss hypotheses generated from this survey with respect to factors that may either accelerate or delay symptom onset in AD and the conditions that appear to be associated with successful cognitive aging.

Young People's Risk of Suicide Attempts in Relation to Parental Death: A Population-Based Register Study

ERIC Educational Resources Information Center

Jakobsen, Ida Skytte; Christiansen, Erik

2011-01-01

Background: The objective of this study was to examine the association between the death of a biological parent and subsequent suicide attempts by young people (aged 10-22 years), and to explore sociodemographic factors as modifying factors in the process. Methods: The study used a nested case-control design. The full study population was obtained…

Registration of a rice gene mapping population of Lemont X Jasmine 85 recombinant inbred lines

USDA-ARS?s Scientific Manuscript database

A mapping population developed from a cross of rice (Oryza sativa L.) tropical japonica cultivar ‘Lemont’ and indica cultivar ‘Jasmine 85’ was developed to facilitate genetic studies for important agronomic traits. The indica- and japonica-based rice recombinant inbred line (RIL) mapping population ...

Prevalence and Factors Associated with Social Avoidance of Recovered SARS Patients in the Hong Kong General Population

ERIC Educational Resources Information Center

Lau, Joseph T. F.; Yang, Xilin; Wong, Eric; Tsui, H. Y.

2006-01-01

The study investigated the general population's perceived infectivity of asymptomatic and recovered severe acute respiratory syndrome (SARS) patients and factors associated with avoidance and discriminatory attitudes, including demographic background, SARS-related perceptions and emotional response to the SARS epidemic. A population-based survey…

Estimating population size in wastewater-based epidemiology. Valencia metropolitan area as a case study.

PubMed

Rico, María; Andrés-Costa, María Jesús; Picó, Yolanda

2017-02-05

Wastewater can provide a wealth of epidemiologic data on common drugs consumed and on health and nutritional problems based on the biomarkers excreted into community sewage systems. One of the biggest uncertainties of these studies is the estimation of the number of inhabitants served by the treatment plants. Twelve human urine biomarkers -5-hydroxyindoleacetic acid (5-HIAA), acesulfame, atenolol, caffeine, carbamazepine, codeine, cotinine, creatinine, hydrochlorothiazide (HCTZ), naproxen, salicylic acid (SA) and hydroxycotinine (OHCOT)- were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) to estimate population size. The results reveal that populations calculated from cotinine, 5-HIAA and caffeine are commonly in agreement with those calculated by the hydrochemical parameters. Creatinine is too unstable to be applicable. HCTZ, naproxen, codeine, OHCOT and carbamazepine, under or overestimate the population compared to the hydrochemical population estimates but showed constant results through the weekdays. The consumption of cannabis, cocaine, heroin and bufotenine in Valencia was estimated for a week using different population calculations. Copyright © 2016 Elsevier B.V. All rights reserved.

Higher dietary anthocyanin and flavonol intakes are associated with anti-inflammatory effects in a population of US adults

USDA-ARS?s Scientific Manuscript database

Background: Although growing evidence from trials and population-based studies has supported a protective role for flavonoids in relation to risk of certain chronic diseases, the underlying mechanisms remain unclear. Several previous studies focused on individual inflammatory biomarkers, but because...

Concepts and controversies in estimating vitamin K status in population based studies

USDA-ARS?s Scientific Manuscript database

A better understanding of vitamin K's role in health and disease requires the assessment of vitamin K nutritional status in population and clinical studies. This is primarily accomplished using dietary questionnaires and/or biomarkers. Because food composition databases in the U.S. are most complete...

Tissues from population-based cancer registries: a novel approach to increasing research potential.

PubMed

Goodman, Marc T; Hernandez, Brenda Y; Hewitt, Stephen; Lynch, Charles F; Coté, Timothy R; Frierson, Henry F; Moskaluk, Christopher A; Killeen, Jeffrey L; Cozen, Wendy; Key, Charles R; Clegg, Limin; Reichman, Marsha; Hankey, Benjamin F; Edwards, Brenda

2005-07-01

Population-based cancer registries, such as those included in the Surveillance, Epidemiology, and End-Results (SEER) Program, offer tremendous research potential beyond traditional surveillance activities. We describe the expansion of SEER registries to gather formalin-fixed, paraffin-embedded tissue from cancer patients on a population basis. Population-based tissue banks have the advantage of providing an unbiased sampling frame for evaluating the public health impact of genes or protein targets that may be used for therapeutic or diagnostic purposes in defined communities. Such repositories provide a unique resource for testing new molecular classification schemes for cancer, validating new biologic markers of malignancy, prognosis and progression, assessing therapeutic targets, and measuring allele frequencies of cancer-associated genetic polymorphisms or germline mutations in representative samples. The assembly of tissue microarrays will allow for the use of rapid, large-scale protein-expression profiling of tumor samples while limiting depletion of this valuable resource. Access to biologic specimens through SEER registries will provide researchers with demographic, clinical, and risk factor information on cancer patients with assured data quality and completeness. Clinical outcome data, such as disease-free survival, can be correlated with previously validated prognostic markers. Furthermore, the anonymity of the study subject can be protected through rigorous standards of confidentiality. SEER-based tissue resources represent a step forward in true, population-based tissue repositories of tumors from US patients and may serve as a foundation for molecular epidemiology studies of cancer in this country.

Common needs but divergent interventions for U.S. homeless and foster care children: results from a systematic review.

PubMed

Zlotnick, Cheryl; Tam, Tammy; Zerger, Suzanne

2012-09-01

Many children living in homeless situations in the U.S. have temporary stays in foster care, and both populations suffer disproportionately higher rates of physical, psychological and social difficulties compared with other children. However, very little is known about which specific interventions achieve the best outcomes for children in these overlapping transitional living situations. To address this gap, we review existing literature to identify the most promising practices for children living in transition. A standardised vocabulary specific to each of three electronic databases (i.e. Medline, PsychINFO and CINAHL) was employed to identify studies that described an intervention specifically targeting foster care or homeless children and families. Separate systematic searches were conducted for homeless and foster children, and only studies published in English between January 1993 and February 2009 were selected. The final sample (n = 43) of articles described interventions that fell into two categories: mental health (n = 17) and case management (n = 26). No article included a sample containing both homeless and foster care children, and most studies on homeless children used case management interventions while most studies on foster care children focused on mental health interventions. Few articles employed rigorous study designs. Although repeatedly studies have demonstrated the overlap between populations of homeless and foster care children, studies focused on one population or the other. Virtually all studies on both homeless and foster children devised interventions to reduce trauma and family instability; yet, no evidence-based practice addresses the overlapping needs and potentially relevant evidence-based practice for these two populations. An important and vital next step is to establish an effective evidence-based intervention that reduces the impact of trauma on both U.S. populations of children living in transition. © 2012 Blackwell Publishing Ltd.

Greater Cincinnati/Northern Kentucky Stroke Study: volume of first-ever ischemic stroke among blacks in a population-based study.

PubMed

Kissela, B; Broderick, J; Woo, D; Kothari, R; Miller, R; Khoury, J; Brott, T; Pancioli, A; Jauch, E; Gebel, J; Shukla, R; Alwell, K; Tomsick, T

2001-06-01

The volume of ischemic stroke on CT scans has been studied in a standardized fashion in acute stroke therapy trials with median volumes between 10.5 to 55 cm(3). The volume of first-ever ischemic stroke in the population is not known. The first phase of the population-based Greater Cincinnati/Northern Kentucky Stroke Study identified all ischemic strokes occurring in blacks in the greater Cincinnati region between January and June of 1993. The patients in this phase of the study who had a first-ever ischemic clinical stroke were identified, and the volume of ischemic stroke was measured. There were 257 verified clinical cases of ischemic stroke, of which 181 had a first-ever ischemic infarct. Imaging was available for 150 of these patients, and 79 had an infarct on the CT or MRI study that was definitely or possibly related to the clinical symptoms. For these patients, volumetric measurements were performed by means of the modified ellipsoid method. The median volume of first-ever ischemic stroke for the 79 patients was 2.5 cm(3) (interquartile range, 0.5 to 8.8 cm(3)). There was a significant relation between location of lesion and infarct size (P<0.001) and between volume and mechanism of stroke (P=0.001). The volume of first-ever ischemic stroke among blacks in our population-based study is smaller than has been previously reported in acute stroke therapy trials. The large proportion of small, mild strokes in blacks may be an important reason for the low percentage of patients who meet the inclusion criteria for tissue plasminogen activator. Further study is necessary to see if these results are generalizable to a multiracial population.

Performance of Dutch children on the Bayley III: a comparison study of US and Dutch norms.

PubMed

Steenis, Leonie J P; Verhoeven, Marjolein; Hessen, Dave J; van Baar, Anneloes L

2015-01-01

The Bayley Scales of Infant and Toddler Development-third edition (Bayley-III) are frequently used to assess early child development worldwide. However, the original standardization only included US children, and it is still unclear whether or not these norms are adequate for use in other populations. Recently, norms for the Dutch version of the Bayley-III (The Bayley-III-NL) were made. Scores based on Dutch and US norms were compared to study the need for population-specific norms. Scaled scores based on Dutch and US norms were compared for 1912 children between 14 days and 42 months 14 days. Next, the proportions of children scoring < 1-SD and < -2 SD based on the two norms were compared, to identify over- or under-referral for developmental delay resulting from non-population-based norms. Scaled scores based on Dutch norms fluctuated around values based on US norms on all subtests. The extent of the deviations differed across ages and subtests. Differences in means were significant across all five subtests (p < .01) with small to large effect sizes (ηp2) ranging from .03 to .26). Using the US instead of Dutch norms resulted in over-referral regarding gross motor skills, and under-referral regarding cognitive, receptive communication, expressive communication, and fine motor skills. The Dutch norms differ from the US norms for all subtests and these differences are clinically relevant. Population specific norms are needed to identify children with low scores for referral and intervention, and to facilitate international comparisons of population data.

Inference and Analysis of Population Structure Using Genetic Data and Network Theory

PubMed Central

Greenbaum, Gili; Templeton, Alan R.; Bar-David, Shirli

2016-01-01

Clustering individuals to subpopulations based on genetic data has become commonplace in many genetic studies. Inference about population structure is most often done by applying model-based approaches, aided by visualization using distance-based approaches such as multidimensional scaling. While existing distance-based approaches suffer from a lack of statistical rigor, model-based approaches entail assumptions of prior conditions such as that the subpopulations are at Hardy-Weinberg equilibria. Here we present a distance-based approach for inference about population structure using genetic data by defining population structure using network theory terminology and methods. A network is constructed from a pairwise genetic-similarity matrix of all sampled individuals. The community partition, a partition of a network to dense subgraphs, is equated with population structure, a partition of the population to genetically related groups. Community-detection algorithms are used to partition the network into communities, interpreted as a partition of the population to subpopulations. The statistical significance of the structure can be estimated by using permutation tests to evaluate the significance of the partition’s modularity, a network theory measure indicating the quality of community partitions. To further characterize population structure, a new measure of the strength of association (SA) for an individual to its assigned community is presented. The strength of association distribution (SAD) of the communities is analyzed to provide additional population structure characteristics, such as the relative amount of gene flow experienced by the different subpopulations and identification of hybrid individuals. Human genetic data and simulations are used to demonstrate the applicability of the analyses. The approach presented here provides a novel, computationally efficient model-free method for inference about population structure that does not entail assumption of prior conditions. The method is implemented in the software NetStruct (available at https://giligreenbaum.wordpress.com/software/). PMID:26888080

The dynamic influence of human resources on evidence-based intervention sustainability and population outcomes: an agent-based modeling approach.

PubMed

McKay, Virginia R; Hoffer, Lee D; Combs, Todd B; Margaret Dolcini, M

2018-06-05

Sustaining evidence-based interventions (EBIs) is an ongoing challenge for dissemination and implementation science in public health and social services. Characterizing the relationship among human resource capacity within an agency and subsequent population outcomes is an important step to improving our understanding of how EBIs are sustained. Although human resource capacity and population outcomes are theoretically related, examining them over time within real-world experiments is difficult. Simulation approaches, especially agent-based models, offer advantages that complement existing methods. We used an agent-based model to examine the relationships among human resources, EBI delivery, and population outcomes by simulating provision of an EBI through a hypothetical agency and its staff. We used data from existing studies examining a widely implemented HIV prevention intervention to inform simulation design, calibration, and validity. Once we developed a baseline model, we used the model as a simulated laboratory by systematically varying three human resource variables: the number of staff positions, the staff turnover rate, and timing in training. We tracked the subsequent influence on EBI delivery and the level of population risk over time to describe the overall and dynamic relationships among these variables. Higher overall levels of human resource capacity at an agency (more positions) led to more extensive EBI delivery over time and lowered population risk earlier in time. In simulations representing the typical human resource investments, substantial influences on population risk were visible after approximately 2 years and peaked around 4 years. Human resources, especially staff positions, have an important impact on EBI sustainability and ultimately population health. A minimum level of human resources based on the context (e.g., size of the initial population and characteristics of the EBI) is likely needed for an EBI to have a meaningful impact on population outcomes. Furthermore, this model demonstrates how ABMs may be leveraged to inform research design and assess the impact of EBI sustainability in practice.

Inference and Analysis of Population Structure Using Genetic Data and Network Theory.

PubMed

Greenbaum, Gili; Templeton, Alan R; Bar-David, Shirli

2016-04-01

Clustering individuals to subpopulations based on genetic data has become commonplace in many genetic studies. Inference about population structure is most often done by applying model-based approaches, aided by visualization using distance-based approaches such as multidimensional scaling. While existing distance-based approaches suffer from a lack of statistical rigor, model-based approaches entail assumptions of prior conditions such as that the subpopulations are at Hardy-Weinberg equilibria. Here we present a distance-based approach for inference about population structure using genetic data by defining population structure using network theory terminology and methods. A network is constructed from a pairwise genetic-similarity matrix of all sampled individuals. The community partition, a partition of a network to dense subgraphs, is equated with population structure, a partition of the population to genetically related groups. Community-detection algorithms are used to partition the network into communities, interpreted as a partition of the population to subpopulations. The statistical significance of the structure can be estimated by using permutation tests to evaluate the significance of the partition's modularity, a network theory measure indicating the quality of community partitions. To further characterize population structure, a new measure of the strength of association (SA) for an individual to its assigned community is presented. The strength of association distribution (SAD) of the communities is analyzed to provide additional population structure characteristics, such as the relative amount of gene flow experienced by the different subpopulations and identification of hybrid individuals. Human genetic data and simulations are used to demonstrate the applicability of the analyses. The approach presented here provides a novel, computationally efficient model-free method for inference about population structure that does not entail assumption of prior conditions. The method is implemented in the software NetStruct (available at https://giligreenbaum.wordpress.com/software/). Copyright © 2016 by the Genetics Society of America.

First experiences in the implementation of biometric technology to link data from Health and Demographic Surveillance Systems with health facility data

PubMed Central

Serwaa-Bonsu, Adwoa; Herbst, Abraham J.; Reniers, Georges; Ijaa, Wilfred; Clark, Benjamin; Kabudula, Chodziwadziwa; Sankoh, Osman

2010-01-01

Background In developing countries, Health and Demographic Surveillance Systems (HDSSs) provide a framework for tracking demographic and health dynamics over time in a defined geographical area. Many HDSSs co-exist with facility-based data sources in the form of Health Management Information Systems (HMIS). Integrating both data sources through reliable record linkage could provide both numerator and denominator populations to estimate disease prevalence and incidence rates in the population and enable determination of accurate health service coverage. Objective To measure the acceptability and performance of fingerprint biometrics to identify individuals in demographic surveillance populations and those attending health care facilities serving the surveillance populations. Methodology Two HDSS sites used fingerprint biometrics for patient and/or surveillance population participant identification. The proportion of individuals for whom a fingerprint could be successfully enrolled were characterised in terms of age and sex. Results Adult (18–65 years) fingerprint enrolment rates varied between 94.1% (95% CI 93.6–94.5) for facility-based fingerprint data collection at the Africa Centre site to 96.7% (95% CI 95.9–97.6) for population-based fingerprint data collection at the Agincourt site. Fingerprint enrolment rates in children under 1 year old (Africa Centre site) were only 55.1% (95% CI 52.7–57.4). By age 5, child fingerprint enrolment rates were comparable to those of adults. Conclusion This work demonstrates the feasibility of fingerprint-based individual identification for population-based research in developing countries. Record linkage between demographic surveillance population databases and health care facility data based on biometric identification systems would allow for a more comprehensive evaluation of population health, including the ability to study health service utilisation from a population perspective, rather than the more restrictive health service perspective. PMID:20200659

Do we need demographic data to forecast plant population dynamics?

USGS Publications Warehouse

Tredennick, Andrew T.; Hooten, Mevin B.; Adler, Peter B.

2017-01-01

Rapid environmental change has generated growing interest in forecasts of future population trajectories. Traditional population models built with detailed demographic observations from one study site can address the impacts of environmental change at particular locations, but are difficult to scale up to the landscape and regional scales relevant to management decisions. An alternative is to build models using population-level data that are much easier to collect over broad spatial scales than individual-level data. However, it is unknown whether models built using population-level data adequately capture the effects of density-dependence and environmental forcing that are necessary to generate skillful forecasts.Here, we test the consequences of aggregating individual responses when forecasting the population states (percent cover) and trajectories of four perennial grass species in a semi-arid grassland in Montana, USA. We parameterized two population models for each species, one based on individual-level data (survival, growth and recruitment) and one on population-level data (percent cover), and compared their forecasting accuracy and forecast horizons with and without the inclusion of climate covariates. For both models, we used Bayesian ridge regression to weight the influence of climate covariates for optimal prediction.In the absence of climate effects, we found no significant difference between the forecast accuracy of models based on individual-level data and models based on population-level data. Climate effects were weak, but increased forecast accuracy for two species. Increases in accuracy with climate covariates were similar between model types.In our case study, percent cover models generated forecasts as accurate as those from a demographic model. For the goal of forecasting, models based on aggregated individual-level data may offer a practical alternative to data-intensive demographic models. Long time series of percent cover data already exist for many plant species. Modelers should exploit these data to predict the impacts of environmental change.

Analysis of anatomic variability in children with low mathematical skills

NASA Astrophysics Data System (ADS)

Han, Zhaoying; Fuchs, Lynn; Davis, Nikki; Cannistraci, Christopher J.; Anderson, Adam W.; Gore, John C.; Dawant, Benoit M.

2008-03-01

Mathematical difficulty affects approximately 5-9% of the population. Studies on individuals with dyscalculia, a neurologically based math disorder, provide important insight into the neural correlates of mathematical ability. For example, cognitive theories, neuropsychological studies, and functional neuroimaging studies in individuals with dyscalculia suggest that the bilateral parietal lobes and intraparietal sulcus are central to mathematical performance. The purpose of the present study was to investigate morphological differences in a group of third grade children with poor math skills. We compare population averages of children with low math skill (MD) to gender and age matched controls with average math ability. Anatomical data were gathered with high resolution MRI and four different population averaging methods were used to study the effect of the normalization technique on the results. Statistical results based on the deformation fields between the two groups show anatomical differences in the bilateral parietal lobes, right frontal lobe, and left occipital/parietal lobe.

Mindfulness-Based Interventions for Older Adults: A Review of the Effects on Physical and Emotional Well-being

PubMed Central

Geiger, Paul J.; Boggero, Ian A.; Brake, C. Alex; Caldera, Carolina A.; Combs, Hannah L.; Peters, Jessica R.; Baer, Ruth A.

2015-01-01

This comprehensive review examined the effects of mindfulness-based interventions on the physical and emotional wellbeing of older adults, a rapidly growing segment of the general population. Search procedures yielded 15 treatment outcome studies meeting inclusion criteria. Support was found for the feasibility and acceptability of mindfulness-based interventions with older adults. Physical and emotional wellbeing outcome variables offered mixed support for the use of mindfulness-based interventions with older adults. Potential explanations of mixed findings may include methodological flaws, study limitations, and inconsistent modifications of protocols. These are discussed in detail and future avenues of research are discussed, emphasizing the need to incorporate geriatric populations into future mindfulness-based empirical research. PMID:27200109

Towards Evidence-Based Practice in Language Intervention for Bilingual Children

ERIC Educational Resources Information Center

Thordardottir, Elin

2010-01-01

Evidence-based practice requires that clinical decisions be based on evidence from rigorously controlled research studies. At this time, very few studies have directly examined the efficacy of clinical intervention methods for bilingual children. Clinical decisions for this population cannot, therefore, be based on the strongest forms of research…

Does marital status predict the odds of suicidal death in taiwan? A seven-year population-based study.

PubMed

Yeh, Jui-Yuan; Xirasagar, Sudha; Liu, Tsai-Ching; Li, Chong-Yi; Lin, Herng-Ching

2008-06-01

Using nationwide, 7-year population-based data for 1997-2003, we examined marital status to see if it predicted suicide among the ethnic Chinese population of Taiwan. Using cause of death data, with a case-control design, two groups-total adult suicide deaths, n = 17,850, the study group, and adult deaths other than suicide, n = 71,400 (randomly selected from age, sex, and geographic region matched controls, four per suicide)-were studied. Using multiple logistic regression analysis including age-marital status interaction, adjusted estimates show divorced status to be the most detrimental for suicide propensity, with males showing stronger effect size. Females never married, aged below 35 and 65-plus, and widowed 65-plus had lower suicide odds.

Key Design Considerations When Calculating Cost Savings for Population Health Management Programs in an Observational Setting.

PubMed

Murphy, Shannon M E; Hough, Douglas E; Sylvia, Martha L; Dunbar, Linda J; Frick, Kevin D

2018-02-08

To illustrate the impact of key quasi-experimental design elements on cost savings measurement for population health management (PHM) programs. Population health management program records and Medicaid claims and enrollment data from December 2011 through March 2016. The study uses a difference-in-difference design to compare changes in cost and utilization outcomes between program participants and propensity score-matched nonparticipants. Comparisons of measured savings are made based on (1) stable versus dynamic population enrollment and (2) all eligible versus enrolled-only participant definitions. Options for the operationalization of time are also discussed. Individual-level Medicaid administrative and claims data and PHM program records are used to match study groups on baseline risk factors and assess changes in costs and utilization. Savings estimates are statistically similar but smaller in magnitude when eliminating variability based on duration of population enrollment and when evaluating program impact on the entire target population. Measurement in calendar time, when possible, simplifies interpretability. Program evaluation design elements, including population stability and participant definitions, can influence the estimated magnitude of program savings for the payer and should be considered carefully. Time specifications can also affect interpretability and usefulness. © Health Research and Educational Trust.

Economic Impact of Dyspepsia in Rural and Urban Malaysia: A Population-Based Study

PubMed Central

Yadav, Hematram; Everett, Simon M; Goh, Khean-Lee

2012-01-01

Background/Aims The economic impact of dyspepsia in regions with a diverse healthcare system remains uncertain. This study aimed to estimate the costs of dyspepsia in a rural and urban population in Malaysia. Methods Economic evaluation was performed based on the cost-of-illness method. Resource utilization and quality of life data over a specific time frame, were collected to determine direct, indirect and intangible costs related to dyspepsia. Results The prevalences of dyspepsia in the rural (n = 2,000) and urban (n = 2,039) populations were 14.6% and 24.3% respectively. Differences in socioeconomic status and healthcare utilisation between both populations were considerable. The cost of dyspepsia per 1,000 population per year was estimated at USD14,816.10 and USD59,282.20 in the rural and urban populations respectively. The cost per quality adjusted life year for dyspepsia in rural and urban adults was USD16.30 and USD69.75, respectively. Conclusions The economic impact of dyspepsia is greater in an urban compared to a rural setting. Differences in socioeconomic status and healthcare utilisation between populations are thought to contribute to this difference. PMID:22323987

The Influence of Physical Activity, Sport and Exercise Motives among UK-Based University Students

ERIC Educational Resources Information Center

Roberts, Simon; Reeves, Matthew; Ryrie, Angus

2015-01-01

Recent evidence suggests that the majority of the adult population fails to achieve the recommended target of 30-minutes moderate intensity exercise, days a week. This includes university students who often have the time to engage in physical activity. The aim of this study was to determine exercise motives for a UK-based student population. The…

Understanding Risk and Protective Factors for Child Maltreatment: The Value of Integrated, Population-Based Data

ERIC Educational Resources Information Center

Putnam-Hornstein, Emily; Needell, Barbara; Rhodes, Anne E.

2013-01-01

In this article, we argue for expanded efforts to integrate administrative data systems as a "practical strategy" for developing a richer understanding of child abuse and neglect. Although the study of child maltreatment is often critiqued for being atheoretical, we believe that a more pressing concern is the absence of population-based and…

Socioeconomic Status and the Risk of Suspected Autism Spectrum Disorders among 18-Month-Old Toddlers in Japan: A Population-Based Study

ERIC Educational Resources Information Center

Fujiwara, Takeo

2014-01-01

The association between family socioeconomic status (SES) and the suspected autism spectrum disorder (ASD) status of 18-month-old toddlers was investigated using a population-based sample in Japan, which has a universal healthcare system and a mandatory health checkup system for toddlers. Questionnaires including SES measurements and modified…

Childhood ADHD Is Strongly Associated with a Broad Range of Psychiatric Disorders during Adolescence: A Population-Based Birth Cohort Study

ERIC Educational Resources Information Center

Yoshimasu, Kouichi; Barbaresi, William J.; Colligan, Robert C.; Voigt, Robert G.; Killian, Jill M.; Weaver, Amy L.; Katusic, Slavica K.

2012-01-01

Background: To evaluate associations between attention-deficit/hyperactivity disorder (ADHD) and comorbid psychiatric disorders using research-identified incident cases of ADHD and population-based controls. Methods: Subjects included a birth cohort of all children born 1976-1982 remaining in Rochester, MN after age five (n = 5,718). Among them we…

Men's and Women's Health Beliefs Differentially Predict Coronary Heart Disease Incidence in a Population-Based Sample

ERIC Educational Resources Information Center

Korin, Maya Rom; Chaplin, William F.; Shaffer, Jonathan A.; Butler, Mark J.; Ojie, Mary-Jane; Davidson, Karina W.

2013-01-01

Objective: To examine gender differences in the association between beliefs in heart disease preventability and 10-year incidence of coronary heart disease (CHD) in a population-based sample. Methods: A total of 2,688 Noninstitutionalized Nova Scotians without prior CHD enrolled in the Nova Scotia Health Study (NSHS95) and were followed for 10…

Incidence and Clinical Features of Rare Cutaneous Malignancies in Olmsted County, Minnesota, 2000 to 2010.

PubMed

Tolkachjov, Stanislav N; Schmitt, Adam R; Muzic, John G; Weaver, Amy L; Baum, Christian L

2017-01-01

The incidence of rare cutaneous malignancies is unknown. Current estimates of rare cutaneous malignancy incidences are based on broad epidemiologic data or single institution experiences, not population-based data. To determine the incidence of several rare nonmelanoma skin cancers. The authors conducted a retrospective chart review of a population-based cohort between the years 2000 and 2010. Residents of Olmsted County, Minnesota, who were diagnosed with a biopsy-proven nonmelanoma skin cancer-excluding basal cell carcinoma and squamous cell carcinoma-were included in this study. The primary outcome was tumor incidence. Additionally, the authors extracted patient demographics, tumor characteristics, treatment modalities, and outcomes. The age-adjusted and sex-adjusted incidences per 100,000 persons of multiple rare cutaneous malignancies were: atypical fibroxanthoma (1.8), sebaceous carcinoma (0.8), dermatofibrosarcoma protuberans (0.4), microcystic adnexal carcinoma (0.7), eccrine carcinoma (0.4), eccrine porocarcinoma (0.2), and leiomyosarcoma (0.2). The authors report population-based incidences and clinical characteristics for these rare cutaneous malignancies. The immune status and smoking status of patients and the treatment and outcomes of these tumors are reported. Additional studies in a broader population are needed to further define the epidemiology and outcomes of these malignancies.

A comprehensive risk assessment framework for offsite transportation of inflammable hazardous waste.

PubMed

Das, Arup; Gupta, A K; Mazumder, T N

2012-08-15

A framework for risk assessment due to offsite transportation of hazardous wastes is designed based on the type of event that can be triggered from an accident of a hazardous waste carrier. The objective of this study is to design a framework for computing the risk to population associated with offsite transportation of inflammable and volatile wastes. The framework is based on traditional definition of risk and is designed for conditions where accident databases are not available. The probability based variable in risk assessment framework is substituted by a composite accident index proposed in this study. The framework computes the impacts due to a volatile cloud explosion based on TNO Multi-energy model. The methodology also estimates the vulnerable population in terms of disability adjusted life years (DALY) which takes into consideration the demographic profile of the population and the degree of injury on mortality and morbidity sustained. The methodology is illustrated using a case study of a pharmaceutical industry in the Kolkata metropolitan area. Copyright © 2012 Elsevier B.V. All rights reserved.

Understanding and Measuring LGBTQ Pathways to Health: A Scoping Review of Strengths-Based Health Promotion Approaches in LGBTQ Health Research.

PubMed

Gahagan, Jacqueline; Colpitts, Emily

2017-01-01

Health research traditionally has focused on the health risks and deficits of lesbian, gay, bisexual, transgender, and queer (LGBTQ) populations, obscuring the determinants that can promote health across the life course. Recognizing, appropriately measuring, and rendering visible these determinants of health is paramount to informing appropriate and engaging health policies, services, and systems for LGBTQ populations. The overarching purpose of this article is to provide an overview of the findings of a scoping review aimed at exploring strengths-based health promotion approaches to understanding and measuring LGBTQ health. Specifically, this scoping review examined peer-reviewed, published academic literature to determine (a) existing methodological frameworks for studying LGBTQ health from a strengths-based health promotion approach, and (b) suggestions for future methodological approaches for studying LGBTQ health from a strengths-based health promotion approach. The findings of this scoping review will be used to inform the development of a study aimed at assessing the health of and improving pathways to health services among LGBTQ populations in Nova Scotia, Canada.

Customized versus population-based growth curves: prediction of low body fat percent at term corrected gestational age following preterm birth.

PubMed

Law, Tameeka L; Katikaneni, Lakshmi D; Taylor, Sarah N; Korte, Jeffrey E; Ebeling, Myla D; Wagner, Carol L; Newman, Roger B

2012-07-01

Compare customized versus population-based growth curves for identification of small-for-gestational-age (SGA) and body fat percent (BF%) among preterm infants. Prospective cohort study of 204 preterm infants classified as SGA or appropriate-for-gestational-age (AGA) by population-based and customized growth curves. BF% was determined by air-displacement plethysmography. Differences between groups were compared using bivariable and multivariable linear and logistic regression analyses. Customized curves reclassified 30% of the preterm infants as SGA. SGA infants identified by customized method only had significantly lower BF% (13.8 ± 6.0) than the AGA (16.2 ± 6.3, p = 0.02) infants and similar to the SGA infants classified by both methods (14.6 ± 6.7, p = 0.51). Customized growth curves were a significant predictor of BF% (p = 0.02), whereas population-based growth curves were not a significant independent predictor of BF% (p = 0.50) at term corrected gestational age. Customized growth potential improves the differentiation of SGA infants and low BF% compared with a standard population-based growth curve among a cohort of preterm infants.

Differences between seven measures of self-reported numbers of clients of female sex workers in southern India: implications for individual- and population-level analysis.

PubMed

Deering, Kathleen N; Vickerman, P; Pickles, M; Moses, S; Blanchard, J F; Ramesh, B M; Isac, S; Boily, M-C

2013-02-01

Quantifying sexual activity of sub-populations with high-risk sexual behaviour is important in understanding HIV epidemiology. This study examined inconsistency of seven outcomes measuring self-reported clients per month (CPM) of female sex workers (FSWs) in southern India and implications for individual/population-level analysis. Multivariate negative binomial regression was used to compare key social/environmental factors associated with each outcome. A transmission dynamics model was used to assess the impact of differences between outcomes on population-level FSW/client HIV prevalence. Outcomes based on 'clients per last working day' produced lower estimates than those based on 'clients per typical day'. Although the outcomes were strongly correlated, their averages differed by approximately two-fold (range 39.0-79.1 CPM). The CPM measure chosen did not greatly influence standard epidemiological 'risk factor' analysis. Differences across outcomes influenced HIV prevalence predictions. Due to this uncertainty, we recommend basing population-based estimates on the range of outcomes, particularly when assessing the impact of interventions.

Developing a systems-based framework of the factors influencing dietary and physical activity behaviours in ethnic minority populations living in Europe - a DEDIPAC study.

PubMed

Holdsworth, Michelle; Nicolaou, Mary; Langøien, Lars Jørun; Osei-Kwasi, Hibbah Araba; Chastin, Sebastien F M; Stok, F Marijn; Capranica, Laura; Lien, Nanna; Terragni, Laura; Monsivais, Pablo; Mazzocchi, Mario; Maes, Lea; Roos, Gun; Mejean, Caroline; Powell, Katie; Stronks, Karien

2017-11-07

Some ethnic minority populations have a higher risk of non-communicable diseases than the majority European population. Diet and physical activity behaviours contribute to this risk, shaped by a system of inter-related factors. This study mapped a systems-based framework of the factors influencing dietary and physical activity behaviours in ethnic minority populations living in Europe, to inform research prioritisation and intervention development. A concept mapping approach guided by systems thinking was used: i. Preparation (protocol and terminology); ii. Generating a list of factors influencing dietary and physical activity behaviours in ethnic minority populations living in Europe from evidence (systematic mapping reviews) and 'eminence' (89 participants from 24 academic disciplines via brainstorming, an international symposium and expert review) and; iii. Seeking consensus on structuring, rating and clustering factors, based on how they relate to each other; and iv. Interpreting/utilising the framework for research and interventions. Similar steps were undertaken for frameworks developed for the majority European population. Seven distinct clusters emerged for dietary behaviour (containing 85 factors) and 8 for physical activity behaviours (containing 183 factors). Four clusters were similar across behaviours: Social and cultural environment; Social and material resources; Psychosocial; and Migration context. Similar clusters of factors emerged in the frameworks for diet and physical activity behaviours of the majority European population, except for 'migration context'. The importance of factors across all clusters was acknowledged, but their relative importance differed for ethnic minority populations compared with the majority population. This systems-based framework integrates evidence from both expert opinion and published literature, to map the factors influencing dietary and physical activity behaviours in ethnic minority groups. Our findings illustrate that innovative research and complex interventions need to be developed that are sensitive to the needs of ethnic minority populations. A systems approach that encompasses the complexity of the inter-related factors that drive behaviours may inform a more holistic public health paradigm to more effectively reach ethnic minorities living in Europe, as well as the majority host population.

Controversial opinion: evaluation of EGR1 and LAMA2 loci for high myopia in Chinese populations.

PubMed

Lin, Fang-yu; Huang, Zhu; Lu, Ning; Chen, Wei; Fang, Hui; Han, Wei

2016-03-01

Functional studies have suggested the important role of early growth response 1 (EGR1) and Laminin α2-chain (LAMA2) in human eye development. Genetic studies have reported a significant association of the single nucleotide polymorphism (SNP) in the LAMA2 gene with myopia. This study aimed to evaluate the association of the tagging SNPs (tSNPs) in the EGR1 and LAMA2 genes with high myopia in two independent Han Chinese populations. Four tSNPs (rs11743810 in the EGR1 gene; rs2571575, rs9321170, and rs1889891 in the LAMA2 gene) were selected, according to the HapMap database (http://hapmap.ncbi.nlm.nih.gov), and were genotyped using the ligase detection reaction (LDR) approach for 167 Han Chinese nuclear families with extremely highly myopic offspring (<-10.0 diopters) and an independent group with 485 extremely highly myopic cases (<-10.0 diopters) and 499 controls. Direct sequencing was used to confirm the LDR results in twenty randomly selected subjects. Family-based association analysis was performed using the family-based association test (FBAT) software package (Version 1.5.5). Population-based association analysis was performed using the Chi-square test. The association analysis power was estimated using online software (http://design.cs.ucla.edu). The FBAT demonstrated that all four tSNPs tested did not show association with high myopia (P>0.05). Haplotype analysis of tSNPs in the LAMA2 genes also did not show a significant association (P>0.05). Meanwhile, population-based association analysis also showed no significant association results with high myopia (P>0.05). On the basis of our family- and population-based analyses for the Han Chinese population, we did not find positive association signals of the four SNPs in the LAMA2 and EGR1 genes with high myopia.

IBSEM: An Individual-Based Atlantic Salmon Population Model.

PubMed

Castellani, Marco; Heino, Mikko; Gilbey, John; Araki, Hitoshi; Svåsand, Terje; Glover, Kevin A

2015-01-01

Ecology and genetics can influence the fate of individuals and populations in multiple ways. However, to date, few studies consider them when modelling the evolutionary trajectory of populations faced with admixture with non-local populations. For the Atlantic salmon, a model incorporating these elements is urgently needed because many populations are challenged with gene-flow from non-local and domesticated conspecifics. We developed an Individual-Based Salmon Eco-genetic Model (IBSEM) to simulate the demographic and population genetic change of an Atlantic salmon population through its entire life-cycle. Processes such as growth, mortality, and maturation are simulated through stochastic procedures, which take into account environmental variables as well as the genotype of the individuals. IBSEM is based upon detailed empirical data from salmon biology, and parameterized to reproduce the environmental conditions and the characteristics of a wild population inhabiting a Norwegian river. Simulations demonstrated that the model consistently and reliably reproduces the characteristics of the population. Moreover, in absence of farmed escapees, the modelled populations reach an evolutionary equilibrium that is similar to our definition of a 'wild' genotype. We assessed the sensitivity of the model in the face of assumptions made on the fitness differences between farm and wild salmon, and evaluated the role of straying as a buffering mechanism against the intrusion of farm genes into wild populations. These results demonstrate that IBSEM is able to capture the evolutionary forces shaping the life history of wild salmon and is therefore able to model the response of populations under environmental and genetic stressors.

An isochrone data base and a rapid model for stellar population synthesis

NASA Astrophysics Data System (ADS)

Li, Zhongmu; Han, Zhanwen

2008-06-01

We first presented an isochrone data base that can be widely used for stellar population synthesis studies and colour-magnitude diagram (CMD) fitting. The data base consists of the isochrones of both single-star and binary-star simple stellar populations (ss-SSPs and bs-SSPs). The ranges for the age and metallicity of populations are 0-15 Gyr and 0.0001-0.03, respectively. All data are available for populations with two widely used initial mass functions (IMFs), that is, Salpeter IMF and Chabrier IMF. The uncertainty caused by the data base (about 0.81 per cent) is designed to be smaller than those caused by the Hurley code and widely used stellar spectra libraries (e.g. BaSeL 3.1) when it is used for stellar population synthesis. Based on the isochrone data base, we then built a rapid stellar population synthesis (RPS) model and calculated the high-resolution (0.3-Å) integrated spectral energy distributions, Lick indices and colour indices for bs-SSPs and ss-SSPs. In particular, we calculated the UBVRIJHKLM colours, ugriz colours and some composite colours that consist of magnitudes on different systems. These colours are useful for disentangling the well-known stellar age-metallicity degeneracy according to our previous work. As an example for applying the isochrone data base for CMD fitting, we fitted the CMDs of two star clusters (M67 and NGC1868) and obtained their distance moduli, colour excesses, stellar metallicities and ages. The results showed that the isochrones of bs-SSPs are closer to those of real star clusters. It suggests that we should take the effects of binary interactions into account in stellar population synthesis. We also discussed on the limitations of the application of the isochrone data base and the results of the RPS model. All the data are available at the CDS or on request to the authors. E-mail: zhongmu.li@gmail.com

What is the most bothersome lower urinary tract symptom? Individual- and population-level perspectives for both men and women.

PubMed

Agarwal, Arnav; Eryuzlu, Leyla N; Cartwright, Rufus; Thorlund, Kristian; Tammela, Teuvo L J; Guyatt, Gordon H; Auvinen, Anssi; Tikkinen, Kari A O

2014-06-01

No study has compared the bothersomeness of all lower urinary tract symptoms (LUTS) using a population-based sample of adults. Despite this lack of evidence, investigators have often cited their LUTS of interest as the "most bothersome" or "one of the most bothersome." To compare the population- and individual-level burden of LUTS in men and women. In this population-based cross-sectional study, questionnaires were mailed to 6000 individuals (18-79 yr of age) randomly identified from the Finnish Population Register. The validated Danish Prostatic Symptom Score questionnaire was used for assessment of bother of 12 different LUTS. The age-standardized prevalence of at least moderate bother was calculated for each symptom (population-level burden). Among symptomatic individuals, the proportion of affected individuals with at least moderate bother was calculated for each symptom (individual-level bother). A total of 3727 individuals (62.4%) participated (53.7% female). The LUTS with the greatest population-level burden were urgency (7.9% with at least moderate bother), stress urinary incontinence (SUI) (6.5%), nocturia (6.0%), postmicturition dribble (5.8%), and urgency urinary incontinence (UUI) (5.0%). Burden from incontinence symptoms was higher in women than men, and the opposite was true for voiding and postmicturition symptoms. At the individual level, UUI was the most bothersome for both genders. Although the response proportion was high, approximately a third did not participate. Both men and women with UUI report moderate or major bother more frequently than individuals with other LUTS. At the population level, the most prevalent bothersome symptoms are urgency, SUI, and nocturia. Urinary urgency was the most common troubling symptom in a large population-based study; however, for individuals, urgency incontinence was the most likely to be rated as bothersome. Copyright © 2014 European Association of Urology. All rights reserved.

Mapping the Risk of Snakebite in Sri Lanka - A National Survey with Geospatial Analysis

PubMed Central

Ediriweera, Dileepa Senajith; Kasturiratne, Anuradhani; Pathmeswaran, Arunasalam; Gunawardena, Nipul Kithsiri; Wijayawickrama, Buddhika Asiri; Jayamanne, Shaluka Francis; Isbister, Geoffrey Kennedy; Dawson, Andrew; Giorgi, Emanuele; Diggle, Peter John; Lalloo, David Griffith; de Silva, Hithanadura Janaka

2016-01-01

Background There is a paucity of robust epidemiological data on snakebite, and data available from hospitals and localized or time-limited surveys have major limitations. No study has investigated the incidence of snakebite across a whole country. We undertook a community-based national survey and model based geostatistics to determine incidence, envenoming, mortality and geographical pattern of snakebite in Sri Lanka. Methodology/Principal Findings The survey was designed to sample a population distributed equally among the nine provinces of the country. The number of data collection clusters was divided among districts in proportion to their population. Within districts clusters were randomly selected. Population based incidence of snakebite and significant envenoming were estimated. Model-based geostatistics was used to develop snakebite risk maps for Sri Lanka. 1118 of the total of 14022 GN divisions with a population of 165665 (0.8%of the country’s population) were surveyed. The crude overall community incidence of snakebite, envenoming and mortality were 398 (95% CI: 356–441), 151 (130–173) and 2.3 (0.2–4.4) per 100000 population, respectively. Risk maps showed wide variation in incidence within the country, and snakebite hotspots and cold spots were determined by considering the probability of exceeding the national incidence. Conclusions/Significance This study provides community based incidence rates of snakebite and envenoming for Sri Lanka. The within-country spatial variation of bites can inform healthcare decision making and highlights the limitations associated with estimates of incidence from hospital data or localized surveys. Our methods are replicable, and these models can be adapted to other geographic regions after re-estimating spatial covariance parameters for the particular region. PMID:27391023

Epidemiology of haemolytic uremic syndrome in children. Data from the North Italian HUS network.

PubMed

Ardissino, Gianluigi; Salardi, Stefania; Colombo, Elisa; Testa, Sara; Borsa-Ghiringhelli, Nicolò; Paglialonga, Fabio; Paracchini, Valentina; Tel, Francesca; Possenti, Ilaria; Belingheri, Mirco; Civitillo, Cristina Felice; Sardini, Stefano; Ceruti, Rossella; Baldioli, Carlo; Tommasi, Paola; Parola, Luciana; Russo, Fiorella; Tedeschi, Silvana

2016-04-01

Despite the severity of HUS and the fact that it represents a leading cause of acute kidney injury in children, the general epidemiology of HUS is all but well documented. The present study provides updated, population-based, purely epidemiological information on HUS in childhood from a large and densely populated area of northern Italy (9.6 million inhabitants, 1.6 million children). We systematically reviewed the files concerning patients with STEC-HUS and atypical HUS (aHUS) over a 10-year observation period (January 2003-December 2012). We included all incident cases with a documented first episode of HUS before the age of 18 years. We identified 101 cases of HUS during the 10 years. The overall mean annual incidence was 6.3 cases/million children aged <18 years (range 1.9-11.9), and 15.7/million of age-related population (MARP) among subjects aged <5 years; aHUS accounted for 11.9 % of the cases (mean incidence 0.75/MARP). The overall case fatality rate was 4.0 % (3.4 % STEC-HUS, 8.3 % aHUS). Given the public health impact of HUS, this study provides recent, population-based epidemiological data useful for healthcare planning and particularly for estimating the financial burden that healthcare providers might have to face in treating HUS, whose incidence rate seems to increase in Northern Italy. • HUS is a rare disease, but it represents the leading cause of acute kidney injury in children worldwide. • STEC-HUS (also called typical, D + HUS) is more common compared to atypical HUS, but recent, population-based epidemiological data (incidence) are scanty. What is New: • Comprehensive, population-based epidemiological data concerning both typical and atypical HUS based on a long observational period.

Costs of detection bias in index-based population monitoring

USGS Publications Warehouse

Moore, C.T.; Kendall, W.L.

2004-01-01

Managers of wildlife populations commonly rely on indirect, count-based measures of the population in making decisions regarding conservation, harvest, or control. The main appeal in the use of such counts is their low material expense compared to methods that directly measure the population. However, their correct use rests on the rarely-tested but often-assumed premise that they proportionately reflect population size, i.e., that they constitute a population index. This study investigates forest management for the endangered Red-cockaded Woodpecker (Picoides borealis) and the Wood Thrush (Hylocichla mustelina) at the Piedmont National Wildlife Refuge in central Georgia, U.S.A. Optimal decision policies for a joint species objective were derived for two alternative models of Wood Thrush population dynamics. Policies were simulated under scenarios of unbiasedness, consistent negative bias, and habitat-dependent negative bias in observed Wood Thrush densities. Differences in simulation outcomes between biased and unbiased detection scenarios indicated the expected loss in resource objectives (here, forest habitat and birds) through decision-making based on biased population counts. Given the models and objective function used in our analysis, expected losses were as great as 11%, a degree of loss perhaps not trivial for applications such as endangered species management. Our analysis demonstrates that costs of uncertainty about the relationship between the population and its observation can be measured in units of the resource, costs which may offset apparent savings achieved by collecting uncorrected population counts.

Sun Exposure Prevalence and Associated Skin Health Habits: Results from the Austrian Population-Based UVSkinRisk Survey

PubMed Central

Haluza, Daniela; Simic, Stana; Moshammer, Hanns

2016-01-01

Recreational sun exposure accounts for a large number of acute and chronic dermatological diseases, including skin cancer. This study aimed at estimating the one-year prevalence of sun exposure and skin health-associated knowledge and attitudes among Austrian citizens. The population-based UVSkinRisk survey investigated a representative sample of Austrian adults using a structured questionnaire. In total, 1500 study subjects (median age 33.0 years, 50.5% females) participated in this questionnaire survey. Among study participants, prevalence of sun exposure was 47%, with slightly higher rates in males (48%) compared to females (46%). Younger age, lower professional category, darker skin type, motives to tan, sunbed use, sunburn, and outdoor sport activity increased the odds for prevalent sun exposure. This is the first population-based study evaluating the prevailing sun exposure and recreational habits influencing skin health among Austrian citizens. Despite public media campaigns educating on the harmful effects of sunlight exposure, we found a high prevalence of self-reported sunlight exposure. The results suggest that multifaceted socio-cultural characteristics stimulate recreational sun exposure and tanning habits. Communicating individualized Public (Skin) Health messages might be the key to prevent photo-induced skin health hazards in light-skinned populations. The practical and theoretical implications of these findings are discussed. PMID:26797627

Hospital-based epidemiological and clinical characterisation of the malignant transformation of oral leukoplakia in a Chinese population.

PubMed

Lyu, Ming-Yue; Guo, Yu-Si; Li, Shuo; Yang, Di; Hua, Hong

2017-08-01

The aim of this review was to analyse, systematically, hospital-based epidemiological information concerning the malignant transformation rate (MTR) of oral leukoplakia (OL) in a Chinese population, as well as the associated risk factors. Four electronic databases were searched for studies dealing with OL and related risk factors, including age, gender, type of lesion, site, and smoking and drinking habits. The MTR of OL in the hospital-based Chinese population ranged from 4% to 13%, based on the studies analysed. Regarding risk factors, we found that female patients had a higher MTR than male patients, and that patients older than 50 years of age also had a higher MTR. Patients who smoked had a lower MTR, while alcohol consumption seemed to have no association with MTR. Malignant transformation occurred most commonly on the tongue. Regarding lesion type, non-homogeneous OL had a higher MTR, with the granular type having the highest MTR. Our results regarding the epidemiology of OL showed a similar trend to those reported in western populations and provided preliminary epidemiological information on the Chinese population. Our findings show that female gender, age >50 years and non-homogeneous OL are risk factors for malignant transformation. It is important to develop clinical strategies to educate, diagnose and treat patients with OL and to minimise the MTR of OL. © 2017 FDI World Dental Federation.

[Kawasaki disease is more prevalent in rural areas of Catalonia (Spain)].

PubMed

Sánchez-Manubens, Judith; Antón, Jordi; Bou, Rosa; Iglesias, Estibaliz; Calzada-Hernandez, Joan; Rodó, Xavier; Morguí, Josep-Antón

2017-10-01

Kawasaki disease (KD) is an acute self-limited systemic vasculitis relatively common in childhood. The etiology of KD is still unknown, although clinical, laboratory and epidemiological features suggest an infectious origin or trigger. Differences on incidence between countries have been related to specific genetic factors, ethnicity, country of birth and some other sociocultural and environmental factors. We present a population-based study on incidence of KD in Catalonia (Spain), focusing on differences between patients in rural and non-rural areas of the region. Observational population-based study including all Pediatric Units in Catalan hospitals, between 2004 and 2014. A 12-month (March 2013-March 2014) prospective collection of new cases of KD was carried out to determine the incidence of KD. The rest of the data was retrieved retrospectively. Data from 399 patients over the 10-year study period was analyzed. Among the total KD patients, 353 (88.5%) lived in non-rural areas and 46 (11.5%) in rural areas. It was found that there is a significant difference (P<.001) between the percentage of rural population observed in patients with KD (11.5%), and the expected 5% of the Catalan population. This is the first population-based study showing significant differences on KD incidence rates between rural and non-rural areas. Copyright © 2016 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

Evaluating the Impact of an Accountable Care Organization on Population Health: The Quasi-Experimental Design of the German Gesundes Kinzigtal.

PubMed

Pimperl, Alexander; Schulte, Timo; Mühlbacher, Axel; Rosenmöller, Magdalena; Busse, Reinhard; Groene, Oliver; Rodriguez, Hector P; Hildebrandt, Helmut

2017-06-01

A central goal of accountable care organizations (ACOs) is to improve the health of their accountable population. No evidence currently links ACO development to improved population health. A major challenge to establishing the evidence base for the impact of ACOs on population health is the absence of a theoretically grounded, robust, operationally feasible, and meaningful research design. The authors present an evaluation study design, provide an empirical example, and discuss considerations for generating the evidence base for ACO implementation. A quasi-experimental study design using propensity score matching in combination with small-scale exact matching is implemented. Outcome indicators based on claims data were constructed and analyzed. Population health is measured by using a range of mortality indicators: mortality ratio, age at time of death, years of potential life lost/gained, and survival time. The application is assessed using longitudinal data from Gesundes Kinzigtal, one of the leading population-based ACOs in Germany. The proposed matching approach resulted in a balanced control of observable differences between the intervention (ACO) and control groups. The mortality indicators used indicate positive results. For example, 635.6 fewer years of potential life lost (2005.8 vs. 2641.4; t-test: sig. P < 0.05*) in the ACO intervention group (n = 5411) attributable to the ACO, also after controlling for a potential (indirect) immortal time bias by excluding the first half year after enrollment from the outcome measurement. This empirical example of the impact of a German ACO on population health can be extended to the evaluation of ACOs and other integrated delivery models of care.

[Population dynamics and armed violence in Colombia, 1985-2010].

PubMed

Salaya, Hernán Eduardo; Rodríguez, Jesús

2014-09-01

Describe changes in the population structure of Colombia's municipalities in relation to internal displacement in response to armed violence. A descriptive ecological study was carried out. Secondary sources were consulted, taken from the Consolidated Registry of Displaced Population and from the National Administrative Department of Statistics, to calculate expulsion and reception rates for population displaced by violence from 2002 to 2010. Based on these rates, four groups were created of municipalities in the extreme quartile for each rate during the entire period, which were classified as high expulsion, low expulsion, high reception, and low reception. Subsequently, population pyramids and structure indicators were constructed for each group of municipalities for two comparative reference years (1985 and 2010). Municipalities with high expulsion or reception rates experienced a slower epidemiological transition, with lower mean ages and aging indices. The high expulsion group had the least regression, based on the Sundbärg index. In the high reception group, the masculinity ratio decreased the most, especially among the economically active population, and it had the highest population growth. Population dynamics in Colombia have been affected by armed violence and changes in these dynamics are not uniform across the country, leading to important social, economic, and cultural consequences. This study is useful for decision-making and public policy making.

Exposure to childhood adversity and deficits in emotion recognition: results from a large, population-based sample.

PubMed

Dunn, Erin C; Crawford, Katherine M; Soare, Thomas W; Button, Katherine S; Raffeld, Miriam R; Smith, Andrew D A C; Penton-Voak, Ian S; Munafò, Marcus R

2018-03-07

Emotion recognition skills are essential for social communication. Deficits in these skills have been implicated in mental disorders. Prior studies of clinical and high-risk samples have consistently shown that children exposed to adversity are more likely than their unexposed peers to have emotion recognition skills deficits. However, only one population-based study has examined this association. We analyzed data from children participating in the Avon Longitudinal Study of Parents and Children, a prospective birth cohort (n = 6,506). We examined the association between eight adversities, assessed repeatedly from birth to age 8 (caregiver physical or emotional abuse; sexual or physical abuse; maternal psychopathology; one adult in the household; family instability; financial stress; parent legal problems; neighborhood disadvantage) and the ability to recognize facial displays of emotion measured using the faces subtest of the Diagnostic Assessment of Non-Verbal Accuracy (DANVA) at age 8.5 years. In addition to examining the role of exposure (vs. nonexposure) to each type of adversity, we also evaluated the role of the timing, duration, and recency of each adversity using a Least Angle Regression variable selection procedure. Over three-quarters of the sample experienced at least one adversity. We found no evidence to support an association between emotion recognition deficits and previous exposure to adversity, either in terms of total lifetime exposure, timing, duration, or recency, or when stratifying by sex. Results from the largest population-based sample suggest that even extreme forms of adversity are unrelated to emotion recognition deficits as measured by the DANVA, suggesting the possible immutability of emotion recognition in the general population. These findings emphasize the importance of population-based studies to generate generalizable results. © 2018 Association for Child and Adolescent Mental Health.

Population norms for the EQ-5D-3L: a cross-country analysis of population surveys for 20 countries.

PubMed

Janssen, M F; Szende, A; Cabases, J; Ramos-Goñi, J M; Vilagut, G; König, H H

2018-02-14

This study provides EQ-5D population norms for 20 countries (N = 163,838), which can be used to compare profiles for patients with specific conditions with data for the average person in the general population in a similar age and/or gender group. Descriptive EQ-5D data are provided for the total population, by gender and by seven age groups. Provided index values are based on European VAS for all countries, based on TTO for 11 countries and based on VAS for 10 countries. Important differences exist in EQ-5D reported health status across countries after standardizing for population structure. Self-reported health according to all five dimensions and EQ VAS generally decreased with increasing age and was lower for females. Mean self-rated EQ VAS scores varied from 70.4 to 83.3 in the total population by country. The prior living standards (GDP per capita) in the countries studied are correlated most with the EQ VAS scores (0.58), while unemployment appeared to be significantly correlated in people over the age of 45 only. A country's expenditure on health care correlated moderately with higher ratings on the EQ VAS (0.55). EQ-5D norms can be used as reference data to assess the burden of disease of patients with specific conditions. Such information, in turn, can inform policy-making and assist in setting priorities in health care.

Prevalence and Annual Incidence of Thyroid Disease in Korea from 2006 to 2015: A Nationwide Population-Based Cohort Study.

PubMed

Kwon, Hyemi; Jung, Jin Hyung; Han, Kyung Do; Park, Yong Gyu; Cho, Jung Hwan; Lee, Da Young; Han, Ji Min; Park, Se Eun; Rhee, Eun Jung; Lee, Won Young

2018-06-01

The incidence of thyroid nodules has increased worldwide in recent years. Thyroid dysfunction is a potential risk factor for hypercholesterolemia, cardiovascular disease, osteoporosis, arrhythmia, and neuropsychiatric disease. This study investigated the prevalence and annual incidence of thyroid nodules, hypothyroidism, and hyperthyroidism in Koreans. In this nationwide population-based cohort study, 51,834,660 subjects were included using the National Health Information database from 2006 to 2015, after the exclusion of subjects with thyroid cancer. The prevalence in Korea in 2015 of thyroid nodules, hypothyroidism in patients taking thyroid hormone, and hyperthyroidism in patients undergoing treatment was 15.82/1,000 population, 15.94/1,000 population, and 2.76/1,000 population, respectively. All these diseases were more prevalent among women than among men. The number of incident cases of these three thyroid diseases steadily increased from 2006 to 2012, and then decreased through 2015. The incidence of thyroid nodules, hypothyroidism treated with thyroid hormone, and treated hyperthyroidism was 6.79/1,000 population, 1.76/1,000 population, and 0.55/1,000 population, respectively, in Korea in 2015. The use of methimazole continuously increased, from 33% of total antithyroid drug prescriptions in 2006 to 74.4% in 2015, and it became the most frequently prescribed antithyroid drug in Korea. In contrast, the use of propylthiouracil continuously decreased. This was the first nationwide study of the prevalence and annual incidence of thyroid nodules, hypothyroidism, and hyperthyroidism to take into account recent changes and to include the current status of patients receiving treatment. Copyright © 2018 Korean Endocrine Society.

A Population-Based Intervention for the Prevention of Falls and Fractures in Home Dwelling People 65 Years and Older in South Germany: Protocol

PubMed Central

Rapp, Kilian; Küpper, Michaela; Becker, Clemens; Fischer, Torben; Büchele, Gisela; Benzinger, Petra

2014-01-01

Background Falls and fall-related injuries pose a major threat to older peoples’ health, and are associated with increased morbidity and mortality. In the course of demographic changes, development and implementation of fall prevention strategies have been recognized as an urgent public health challenge. Various risk factors for falls and a number of effective interventions have been recognized. A substantial proportion of falls occur for people who are neither frail nor at high risk. Therefore, population-based approaches reaching the entire older population are needed. Objective The objective of the study presented is the development, implementation, and evaluation of a population-based intervention for the prevention of falls and fall-related injuries in a medium sized city in Germany. Methods The study is designed as a population-based approach. The intervention community is a mid sized city named Reutlingen in southern Germany with a population of 112,700 people. All community dwelling inhabitants 65 years and older are addressed. There are two main measures that are defined: (1) increase of overall physical activity, and (2) reduction of modifiable risk factors for falls such as deficits in strength and balance, home and environmental hazards, impaired vision, unsafe footwear, and improper use of assistive devices. The implementation strategies are developed in a participatory community planning process. These might include, for example, training of professionals and volunteers, improved availability of exercise classes, and education and raising awareness via newspaper, radio, or lectures. Results The study starts in September 2010 and ends in December 2013. It is evaluated primarily by process evaluation as well as by telephone survey. Conclusions Physical activity as a key message entails multiple positive effects with benefits on a range of geriatric symptoms. The strength of the design is the development of implementation strategies in a participatory community planning. The problems that we anticipate are the dependency on the stakeholders’ willingness to participate, and the difficulty of evaluating population-based programs by hard end points. PMID:24686959

Factors associated with quality of life in active childhood epilepsy: a population-based study.

PubMed

Reilly, Colin; Atkinson, Patricia; Das, Krishna B; Chin, Richard F M; Aylett, Sarah E; Burch, Victoria; Gillberg, Christopher; Scott, Rod C; Neville, Brian G R

2015-05-01

Improving health-related quality of life (HRQOL), rather than just reducing seizures, should be the principal goal in comprehensive management of childhood epilepsy. There is a lack of population-based data on predictors of HRQOL in childhood epilepsy. The Children with Epilepsy in Sussex Schools (CHESS) study is a prospective, population-based study involving school-aged children (5-15 years) with active epilepsy (on one or more AED and/or had a seizure in the last year) in a defined geographical area in the UK. Eighty-five of 115 (74% of eligible population) children underwent comprehensive psychological assessment including measures of cognition, behaviour, and motor functioning. Parents of the children completed the Quality of Life in Childhood Epilepsy (QOLCE).Clinical data on eligible children was extracted using a standardised pro forma. Linear regression analysis was undertaken to identify factors significantly associated with total Quality of Life in this population. Factors independently significantly associated (p < .05) with total QOLCE scores were seizures before 24 months, cognitive impairment (IQ < 85), anxiety, and parent reported school attendance difficulty. These factors were also significantly associated with total QOLCE when children with IQ < 50 were excluded from analysis. The majority of factors associated with parent reported HRQOL in active childhood epilepsy are related to neurobehavioural and/or psychosocial aspects of the condition. Copyright © 2015 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

Population pharmacokinetics of busulfan in pediatric and young adult patients undergoing hematopoietic cell transplant: a model-based dosing algorithm for personalized therapy and implementation into routine clinical use.

PubMed

Long-Boyle, Janel R; Savic, Rada; Yan, Shirley; Bartelink, Imke; Musick, Lisa; French, Deborah; Law, Jason; Horn, Biljana; Cowan, Morton J; Dvorak, Christopher C

2015-04-01

Population pharmacokinetic (PK) studies of busulfan in children have shown that individualized model-based algorithms provide improved targeted busulfan therapy when compared with conventional dose guidelines. The adoption of population PK models into routine clinical practice has been hampered by the tendency of pharmacologists to develop complex models too impractical for clinicians to use. The authors aimed to develop a population PK model for busulfan in children that can reliably achieve therapeutic exposure (concentration at steady state) and implement a simple model-based tool for the initial dosing of busulfan in children undergoing hematopoietic cell transplantation. Model development was conducted using retrospective data available in 90 pediatric and young adult patients who had undergone hematopoietic cell transplantation with busulfan conditioning. Busulfan drug levels and potential covariates influencing drug exposure were analyzed using the nonlinear mixed effects modeling software, NONMEM. The final population PK model was implemented into a clinician-friendly Microsoft Excel-based tool and used to recommend initial doses of busulfan in a group of 21 pediatric patients prospectively dosed based on the population PK model. Modeling of busulfan time-concentration data indicates that busulfan clearance displays nonlinearity in children, decreasing up to approximately 20% between the concentrations of 250-2000 ng/mL. Important patient-specific covariates found to significantly impact busulfan clearance were actual body weight and age. The percentage of individuals achieving a therapeutic concentration at steady state was significantly higher in subjects receiving initial doses based on the population PK model (81%) than in historical controls dosed on conventional guidelines (52%) (P = 0.02). When compared with the conventional dosing guidelines, the model-based algorithm demonstrates significant improvement for providing targeted busulfan therapy in children and young adults.

Prevalence of depressive disorders in the elderly.

PubMed

Barua, Ankur; Ghosh, Mihir Kumar; Kar, Nilamadhab; Basilio, Mary Anne

2011-01-01

Community-based mental health studies have revealed that the point prevalence of depressive disorders in the elderly population of the world varies between 10% and 20%, depending on cultural situations. A retrospective study based on analysis of various study reports was conducted, to determine the median prevalence rates of depressive disorders in the elderly population of India and various other countries in the world. All the studies that constituted the sample were conducted between 1955 and 2005. Included are only community-based, cross-sectional surveys and some prospective studies that had not excluded depression at baseline. These studies were conducted on a homogenous community of the elderly population in the world, who were selected by a simple random sampling technique. After applying the inclusion and exclusion criteria on published and indexed articles, 74 original research studies that surveyed a total of 487,275 elderly individuals, in the age group of 60 years and above, residing in various parts of the world, were included for the final analysis. The median prevalence rate and its corresponding interquartile range were calculated. The chi-square test and chi-square for linear trend were applied. A P value of <.05 was considered as statistically significant. The median prevalence rate of depressive disorders in the world for the elderly population was determined to be 10.3% (interquartile range [IQR], 4.7%-16.0%). The median prevalence rate of depression among the elderly Indian population was determined to be 21.9% (IQR, 11.6%-31.1%). Although there was a significant decrease in the trend of world prevalence of geriatric depression, it was significantly higher among Indians, in recent years, than the rest of the world.

[Gypsy moth Lymantria dispar L. in the South Urals: Patterns in population dynamics and modelling].

PubMed

Soukhovolsky, V G; Ponomarev, V I; Sokolov, G I; Tarasova, O V; Krasnoperova, P A

2015-01-01

The analysis is conducted on population dynamics of gypsy moth from different habitats of the South Urals. The pattern of cyclic changes in population density is examined, the assessment of temporal conjugation in time series of gypsy moth population dynamics from separate habitats of the South Urals is carried out, the relationships between population density and weather conditions are studied. Based on the results obtained, a statistical model of gypsy moth population dynamics in the South Urals is designed, and estimations are given of regulatory and modifying factors effects on the population dynamics.

Genetic variations in the Dravidian population of South West coast of India: Implications in designing case-control studies.

PubMed

D'Cunha, Anitha; Pandit, Lekha; Malli, Chaithra

2017-06-01

Indian data have been largely missing from genome-wide databases that provide information on genetic variations in different populations. This hinders association studies for complex disorders in India. This study was aimed to determine whether the complex genetic structure and endogamy among Indians could potentially influence the design of case-control studies for autoimmune disorders in the south Indian population. A total of 12 single nucleotide variations (SNVs) related to genes associated with autoimmune disorders were genotyped in 370 healthy individuals belonging to six different caste groups in southern India. Allele frequencies were estimated; genetic divergence and phylogenetic relationship within the various caste groups and other HapMap populations were ascertained. Allele frequencies for all genotyped SNVs did not vary significantly among the different groups studied. Wright's FSTwas 0.001 per cent among study population and 0.38 per cent when compared with Gujarati in Houston (GIH) population on HapMap data. The analysis of molecular variance results showed a 97 per cent variation attributable to differences within the study population and <1 per cent variation due to differences between castes. Phylogenetic analysis showed a separation of Dravidian population from other HapMap populations and particularly from GIH population. Despite the complex genetic origins of the Indian population, our study indicated a low level of genetic differentiation among Dravidian language-speaking people of south India. Case-control studies of association among Dravidians of south India may not require stratification based on language and caste.

[Comparative study of the population structure and population assignment of sockeye salmon Oncorhynchus nerka from West Kamchatka based on RAPD-PCR and microsatellite polymorphism].

PubMed

Zelenina, D A; Khrustaleva, A M; Volkov, A A

2006-05-01

Using two types of molecular markers, a comparative analysis of the population structure of sockeye salmon from West Kamchatka as well as population assignment of each individual fish were carried out. The values of a RAPD-PCR-based population assignment test (94-100%) were somewhat higher than those based on microsatellite data (74-84%). However, these results seem quite satisfactory because of high polymorphism of the microsatellite loci examined. The UPGMA dendrograms of genetic similarity of three largest spawning populations, constructed using each of the methods, were highly reliable, which was demonstrated by high bootstrap indices (100% in the case of RAPD-PCR; 84 and 100%, in the case of microsatellite analysis), though the resultant trees differed from one another. The different topology of the trees, in our view, is explained by the fact that the employed methods explored different parts of the genome; hence, the obtained results, albeit valid, may not correlate. Thus, to enhance reliability of the results, several methods of analysis should be used concurrently.

Assessing interethnic admixture using an X-linked insertion-deletion multiplex.

PubMed

Ribeiro-Rodrigues, Elzemar Martins; dos Santos, Ney Pereira Carneiro; dos Santos, Andrea Kely Campos Ribeiro; Pereira, Rui; Amorim, António; Gusmão, Leonor; Zago, Marco Antonio; dos Santos, Sidney Emanuel Batista

2009-01-01

In this study, a PCR multiplex was optimized, allowing the simultaneous analysis of 13 X-chromosome Insertion/deletion polymorphisms (INDELs). Genetic variation observed in Africans, Europeans, and Native Americans reveals high inter-population variability. The estimated proportions of X-chromosomes in an admixed population from the Brazilian Amazon region show a predominant Amerindian contribution (approximately 41%), followed by European (approximately 32%) and African (approximately 27%) contributions. The proportion of Amerindian contribution based on X-linked data is similar to the expected value based on mtDNA and Y-chromosome information. The accuracy for assessing interethnic admixture, and the high differentiation between African, European, and Native American populations, demonstrates the suitability of this INDEL set to measure ancestry proportions in three-hybrid populations, as it is the case of Latin American populations.

Evidence for the effect of disease management: is $1 billion a year a good investment?

PubMed

Mattke, Soeren; Seid, Michael; Ma, Sai

2007-12-01

To assess the evidence for the effect of disease management on quality of care, disease control, and cost, with a focus on population-based programs. Literature review. We conducted a literature search for and a structured review of studies on population-based disease management programs, as well as for reviews and meta-analyses of disease management interventions. We identified 3 evaluations of large-scale population-based programs, as well as 10 meta-analyses and 16 systematic reviews, covering 317 unique studies. We found consistent evidence that disease management improves processes of care and disease control but no conclusive support for its effect on health outcomes. Overall, disease management does not seem to affect utilization except for a reduction in hospitalization rates among patients with congestive heart failure and an increase in outpatient care and prescription drug use among patients with depression. When the costs of the intervention were appropriately accounted for and subtracted from any savings, there was no conclusive evidence that disease management leads to a net reduction of direct medical costs. Although disease management seems to improve quality of care, its effect on cost is uncertain. Most of the evidence to date addresses small-scale programs targeting high-risk individuals, while only 3 studies evaluate large population-based interventions, implying that little is known about their effect. Payers and policy makers should remain skeptical about vendor claims and should demand supporting evidence based on transparent and scientifically sound methods.

Distribution of Brazilian dermatologists according to geographic location, population and HDI of municipalities: an ecological study*

PubMed Central

Schmitt, Juliano Vilaverde; Miot, Hélio Amante

2014-01-01

This study investigated the geographic distribution of dermatologists in Brazilian municipalities in relation to the population, regions of the country and human development index. We conducted an ecological study based on data from the 2010 census, the 2010 human development index, and the records of the Brazilian Society of Dermatology. 5565 municipalities and 6718 dermatologists were surveyed. Only 504 (9.1%) municipalities had dermatologists, and accounted for 56.2% of the Brazilian population. The smallest population size and lowest HDI rate that best discriminated municipalities that did not have dermatologists were found to be 28,000 and 0.71, respectively. The average population density of dermatologists in cities was 1/23.000 inhabitants, and variations were independently associated with the HDI, the population of the municipalities and the region of the country. PMID:25387516

Selection bias in population-based cancer case-control studies due to incomplete sampling frame coverage.

PubMed

Walsh, Matthew C; Trentham-Dietz, Amy; Gangnon, Ronald E; Nieto, F Javier; Newcomb, Polly A; Palta, Mari

2012-06-01

Increasing numbers of individuals are choosing to opt out of population-based sampling frames due to privacy concerns. This is especially a problem in the selection of controls for case-control studies, as the cases often arise from relatively complete population-based registries, whereas control selection requires a sampling frame. If opt out is also related to risk factors, bias can arise. We linked breast cancer cases who reported having a valid driver's license from the 2004-2008 Wisconsin women's health study (N = 2,988) with a master list of licensed drivers from the Wisconsin Department of Transportation (WDOT). This master list excludes Wisconsin drivers that requested their information not be sold by the state. Multivariate-adjusted selection probability ratios (SPR) were calculated to estimate potential bias when using this driver's license sampling frame to select controls. A total of 962 cases (32%) had opted out of the WDOT sampling frame. Cases age <40 (SPR = 0.90), income either unreported (SPR = 0.89) or greater than $50,000 (SPR = 0.94), lower parity (SPR = 0.96 per one-child decrease), and hormone use (SPR = 0.93) were significantly less likely to be covered by the WDOT sampling frame (α = 0.05 level). Our results indicate the potential for selection bias due to differential opt out between various demographic and behavioral subgroups of controls. As selection bias may differ by exposure and study base, the assessment of potential bias needs to be ongoing. SPRs can be used to predict the direction of bias when cases and controls stem from different sampling frames in population-based case-control studies.

Combining multiple sources of data to inform conservation of Lesser Prairie-Chicken populations

USGS Publications Warehouse

Ross, Beth; Haukos, David A.; Hagen, Christian A.; Pitman, James

2018-01-01

Conservation of small populations is often based on limited data from spatially and temporally restricted studies, resulting in management actions based on an incomplete assessment of the population drivers. If fluctuations in abundance are related to changes in weather, proper management is especially important, because extreme weather events could disproportionately affect population abundance. Conservation assessments, especially for vulnerable populations, are aided by a knowledge of how extreme events influence population status and trends. Although important for conservation efforts, data may be limited for small or vulnerable populations. Integrated population models maximize information from various sources of data to yield population estimates that fully incorporate uncertainty from multiple data sources while allowing for the explicit incorporation of environmental covariates of interest. Our goal was to assess the relative influence of population drivers for the Lesser Prairie-Chicken (Tympanuchus pallidicinctus) in the core of its range, western and southern Kansas, USA. We used data from roadside lek count surveys, nest monitoring surveys, and survival data from telemetry monitoring combined with climate (Palmer drought severity index) data in an integrated population model. Our results indicate that variability in population growth rate was most influenced by variability in juvenile survival. The Palmer drought severity index had no measurable direct effects on adult survival or mean number of offspring per female; however, there were declines in population growth rate following severe drought. Because declines in population growth rate occurred at a broad spatial scale, declines in response to drought were likely due to decreases in chick and juvenile survival rather than emigration outside of the study area. Overall, our model highlights the importance of accounting for environmental and demographic sources of variability, and provides a thorough method for simultaneously evaluating population demography in response to long-term climate effects.

Injury risk functions based on population-based finite element model responses: Application to femurs under dynamic three-point bending.

PubMed

Park, Gwansik; Forman, Jason; Kim, Taewung; Panzer, Matthew B; Crandall, Jeff R

2018-02-28

The goal of this study was to explore a framework for developing injury risk functions (IRFs) in a bottom-up approach based on responses of parametrically variable finite element (FE) models representing exemplar populations. First, a parametric femur modeling tool was developed and validated using a subject-specific (SS)-FE modeling approach. Second, principal component analysis and regression were used to identify parametric geometric descriptors of the human femur and the distribution of those factors for 3 target occupant sizes (5th, 50th, and 95th percentile males). Third, distributions of material parameters of cortical bone were obtained from the literature for 3 target occupant ages (25, 50, and 75 years) using regression analysis. A Monte Carlo method was then implemented to generate populations of FE models of the femur for target occupants, using a parametric femur modeling tool. Simulations were conducted with each of these models under 3-point dynamic bending. Finally, model-based IRFs were developed using logistic regression analysis, based on the moment at fracture observed in the FE simulation. In total, 100 femur FE models incorporating the variation in the population of interest were generated, and 500,000 moments at fracture were observed (applying 5,000 ultimate strains for each synthesized 100 femur FE models) for each target occupant characteristics. Using the proposed framework on this study, the model-based IRFs for 3 target male occupant sizes (5th, 50th, and 95th percentiles) and ages (25, 50, and 75 years) were developed. The model-based IRF was located in the 95% confidence interval of the test-based IRF for the range of 15 to 70% injury risks. The 95% confidence interval of the developed IRF was almost in line with the mean curve due to a large number of data points. The framework proposed in this study would be beneficial for developing the IRFs in a bottom-up manner, whose range of variabilities is informed by the population-based FE model responses. Specifically, this method mitigates the uncertainties in applying empirical scaling and may improve IRF fidelity when a limited number of experimental specimens are available.

Population-genetic properties of differentiated copy number variations in cattle.

PubMed

Xu, Lingyang; Hou, Yali; Bickhart, Derek M; Zhou, Yang; Hay, El Hamidi Abdel; Song, Jiuzhou; Sonstegard, Tad S; Van Tassell, Curtis P; Liu, George E

2016-03-23

While single nucleotide polymorphism (SNP) is typically the variant of choice for population genetics, copy number variation (CNV) which comprises insertion, deletion and duplication of genomic sequence, is an informative type of genetic variation. CNVs have been shown to be both common in mammals and important for understanding the relationship between genotype and phenotype. However, CNV differentiation, selection and its population genetic properties are not well understood across diverse populations. We performed a population genetics survey based on CNVs derived from the BovineHD SNP array data of eight distinct cattle breeds. We generated high resolution results that show geographical patterns of variations and genome-wide admixture proportions within and among breeds. Similar to the previous SNP-based studies, our CNV-based results displayed a strong correlation of population structure and geographical location. By conducting three pairwise comparisons among European taurine, African taurine, and indicine groups, we further identified 78 unique CNV regions that were highly differentiated, some of which might be due to selection. These CNV regions overlapped with genes involved in traits related to parasite resistance, immunity response, body size, fertility, and milk production. Our results characterize CNV diversity among cattle populations and provide a list of lineage-differentiated CNVs.

The national burden of cerebrovascular diseases in Spain: a population-based study using disability-adjusted life years.

PubMed

Catalá-López, Ferrán; Fernández de Larrea-Baz, Nerea; Morant-Ginestar, Consuelo; Álvarez-Martín, Elena; Díaz-Guzmán, Jaime; Gènova-Maleras, Ricard

2015-04-20

The aim of the present study was to determine the national burden of cerebrovascular diseases in the adult population of Spain. Cross-sectional, descriptive population-based study. We calculated the disability-adjusted life years (DALY) metric using country-specific data from national statistics and epidemiological studies to obtain representative outcomes for the Spanish population. DALYs were divided into years of life lost due to premature mortality (YLLs) and years of life lived with disability (YLDs). DALYs were estimated for the year 2008 by applying demographic structure by sex and age-groups, cause-specific mortality, morbidity data and new disability weights proposed in the recent Global Burden of Disease study. In the base case, neither YLLs nor YLDs were discounted or age-weighted. Uncertainty around DALYs was tested using sensitivity analyses. In Spain, cerebrovascular diseases generated 418,052 DALYs, comprising 337,000 (80.6%) YLLs and 81,052 (19.4%) YLDs. This accounts for 1,113 DALYs per 100,000 population (men: 1,197 and women: 1,033) and 3,912 per 100,000 in those over the age of 65 years (men: 4,427 and women: 2,033). Depending on the standard life table and choice of social values used for calculation, total DALYs varied by 15.3% and 59.9% below the main estimate. Estimates provided here represent a comprehensive analysis of the burden of cerebrovascular diseases at a national level. Prevention and control programmes aimed at reducing the disease burden merit further priority in Spain. Copyright © 2013 Elsevier España, S.L.U. All rights reserved.

Alcohol Drinking, Dyslipidemia, and Diabetes: A Population-based Prospective Cohort Study among Inner Mongolians in China.

PubMed

Liang, Zhu; Qiu, Qiao Yan; Wu, Jia Hui; Zhou, Jing Wen; Xu, Tian; Zhang, Ming Zhi; Zhang, Yong Hong; Zhang, Shao Yan

2016-08-01

No previous studies have evaluated the association between dyslipidemia, alcohol drinking, and diabetes in an Inner Mongolian population. We aimed to evaluate the co-effects of drinking and dyslipidemia on diabetes incidence in this population. The present study was based on 1880 participants from a population-based prospective cohort study among Inner Mongolians living in China. Participants were classified into four subgroups according to their drinking status and dyslipidemia. Multivariate logistic regression analysis and receiver operating characteristic (ROC) curves were used to evaluate the association between alcohol drinking, dyslipidemia, and diabetes. During the follow-up period, 203 participants were found to have developed diabetes. The multivariable-adjusted odds ratios (95% confidence interval) for the incidence of non-dyslipidemia/drinkers, dyslipidemia/non-drinkers, and dyslipidemia/drinkers in diabetic patients were 1.40 (0.82-2.37), 1.73 (1.17-2.55), and 2.31 (1.38-3.87), respectively, when compared with non-dyslipidemia/non-drinkers. The area under the ROC curve for a model containing dyslipidemia and drinking status along with conventional factors (AUC=0.746) was significantly (P=0.003) larger than the one containing only conventional factors (AUC=0.711). The present study showed that dyslipidemia was an independent risk factor for diabetes, and that drinkers with dyslipidemia had the highest risk of diabetes in the Mongolian population. These findings suggest that dyslipidemia and drinking status may be valuable in predicting diabetes incidence. Copyright © 2016 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

Mixed-Methods for Comparing Tobacco Cessation Interventions

PubMed Central

Momin, Behnoosh; Neri, Antonio; Zhang, Lei; Kahende, Jennifer; Duke, Jennifer; Green, Sonya Goode; Malarcher, Ann; Stewart, Sherri L.

2017-01-01

Introduction The National Comprehensive Cancer Control Program (NCCCP) and National Tobacco Control Program (NTCP) are both well-positioned to promote the use of population-based tobacco cessation interventions, such as state quitlines and Web-based interventions. Aims This paper outlines the methodology used to conduct a comparative effectiveness research study of traditional and Web-based tobacco cessation and quitline promotion approaches. Methods A mixed-methods study with three components was designed to address the effect of promotional activities on service usage and the comparative effectiveness of population-based smoking cessation activities across multiple states. Results/Findings The cessation intervention component followed 7,902 smokers (4,307 quitline users and 3,595 Web intervention users) to ascertain prevalence of 30-day abstinence rates 7 months after registering for smoking cessation services. User characteristics and quit success was compared across the two modalities. In the promotions component, reach and use of traditional and innovative promotion strategies were assessed for 24 states, including online advertising, state Web sites, social media, mobile applications, and their effects on quitline call volume. The partnership intervention component studied the extent of collaboration among six selected NCCCPs and NTCPs. Conclusions This study will guide program staff and clinicians with evidence-based recommendations and best practices for implementation of tobacco cessation within their patient and community populations and establish an evidence base that can be used for decision making. PMID:28243318

"Development of Model-Based Air Pollution Exposure Metrics for use in Epidemiologic Studies"

EPA Science Inventory

Population-based epidemiological studies of air pollution have traditionally relied upon imperfect surrogates of personal exposures, such as area-wide ambient air pollution levels based on readily available concentrations from central monitoring sites. U.S. EPA in collaboration w...

DEVELOPMENT OF MODEL-BASED AIR POLLUTION EXPOSURE METRICS FOR USE IN EPIDEMIOLOGIC STUDIES

EPA Science Inventory

Population-based epidemiological studies of air pollution have traditionally relied upon imperfect surrogates of personal exposures, such as area-wide ambient air pollution levels based on readily available concentrations from central monitoring sites. U.S. EPA in collaboration w...

Clinical governance and research ethics as barriers to UK low-risk population-based health research?

PubMed Central

van Teijlingen, Edwin R; Douglas, Flora; Torrance, Nicola

2008-01-01

Background Since the Helsinki Declaration was introduced in 1964 as a code of practice for clinical research, it has generally been agreed that research governance is also needed in the field of public health and health promotion research. Recently, a range of factors led to the development of more stringent bureaucratic procedures, governing the conduct of low-risk population-based health research in the United Kingdom. Methods Our paper highlights a case study of the application process to medical research ethics committees in the United Kingdom for a study of the promotion of physical activity by health care providers. The case study presented here is an illustration of the challenges in conducting low-risk population-based health research. Results Our mixed-methods approach involved a questionnaire survey of and semi-structured interviews with health professionals (who were all healthy volunteers). Since our study does not involve the participation of either patients or the general population, one would expect the application to the relevant research ethics committees to be a formality. This proved not to be the case! Conclusion Research ethics committees could be counter-productive, rather than protecting the vulnerable in the research process, they can stifle low-risk population-based health research. Research ethics in health services research is first and foremost the responsibility of the researcher(s), and we need to learn to trust health service researchers again. The burden of current research governance regulation to address the perceived ethical problems is neither appropriate nor adequate. Senior researchers/academics need to educate and train students and junior researchers in the area of research ethics, whilst at the same time reducing pressures on them that lead to unethical research, such as commercial funding, inappropriate government interference and the pressure to publish. We propose that non-invasive low-risk population-based health studies such as face-to-face interviews with health and social care professionals or postal questionnaire studies with patients on non-sensitive topics are given a waiver or a light touch review. We suggest that this can be achieved through a two-staged ethics application process. The first stage starts with a one or two-page outline application which ethics committees can use as the basis to grant a waiver or request a full application. PMID:19040750

Culturally Grounded Prevention for Minority Youth Populations: A Systematic Review of the Literature

PubMed Central

Lauricella, Michela; Valdez, Jessica K.; Okamoto, Scott K.; Helm, Susana; Zaremba, Colleen

2016-01-01

Contemporary prevention science has focused on the application of cultural adaptations of evidence-based prevention programs for minority youth populations. Far less is known about culturally grounded methods that are intended to organically develop prevention programs within specific populations and communities. This article systematically reviews recent literature on culturally grounded interventions used to prevent health disparities in ethnic minority youth populations. In this review, we assessed 31 peer-reviewed articles published in 2003 or later that fit inclusionary criteria pertaining to the development and evaluation of culturally grounded prevention programs. The evaluated studies indicated different approaches toward cultural grounding, as well as specific populations, geographic regions, and health issues that have been targeted. Specifically, the findings indicated that most of the studies focused on the development and evaluation of culturally grounded HIV/STI and substance abuse prevention programs for Mexican American, African American, and American Indian/Alaska Native youth residing in the South or Southwestern U.S. These studies largely relied on community-based participatory or qualitative research methods to develop programs from the “ground up.” This review has implications for the development of future culturally grounded and culturally adapted prevention programs targeting underserved minority youth populations and geographic regions. Specifically, it identifies populations and regions where culturally grounded prevention efforts are underdeveloped or non-existent, providing some scientific direction for the future development of these types of programs. PMID:26733384

Culturally Grounded Prevention for Minority Youth Populations: A Systematic Review of the Literature.

PubMed

Lauricella, Michela; Valdez, Jessica K; Okamoto, Scott K; Helm, Susana; Zaremba, Colleen

2016-02-01

Contemporary prevention science has focused on the application of cultural adaptations of evidence-based prevention programs for minority youth populations. Far less is known about culturally grounded methods that are intended to organically develop prevention programs within specific populations and communities. This article systematically reviews recent literature on culturally grounded interventions used to prevent health disparities in ethnic minority youth populations. In this review, we assessed 31 peer-reviewed articles published in 2003 or later that fit inclusionary criteria pertaining to the development and evaluation of culturally grounded prevention programs. The evaluated studies indicated different approaches toward cultural grounding, as well as specific populations, geographic regions, and health issues that have been targeted. Specifically, the findings indicated that most of the studies focused on the development and evaluation of culturally grounded HIV/STI and substance abuse prevention programs for Mexican-American, African American, and American Indian/Alaska Native youth residing in the South or Southwestern US. These studies largely relied on community-based participatory or qualitative research methods to develop programs from the "ground up." This review has implications for the development of future culturally grounded and culturally adapted prevention programs targeting underserved minority youth populations and geographic regions. Specifically, it identifies populations and regions where culturally grounded prevention efforts are underdeveloped or non-existent, providing some scientific direction for the future development of these types of programs.

Dynamics of change in local physician supply: an ecological perspective.

PubMed

Jiang, H Joanna; Begun, James W

2002-05-01

The purpose of this study is to employ an ecological framework to identify factors that have an impact on change in local physician supply within the USA. A particular specialty type of patient care physicians in a local market is defined as a physician population. Four physician populations are identified: generalists, medical specialists, surgical specialists, and hospital-based specialists. Based on population ecology theory, the proposed framework explains the growth of a particular physician population by four mechanisms: the intrinsic properties of this physician population; the local market's carrying capacity, which is determined by three environmental dimensions (munificence, concentration, diversity); competition within the same physician population; and interdependence between different physician populations. Data at the level of Metropolitan Statistical Areas (MSAs) were compiled from the US Area Resources File, the American Hospital Association Annual Surveys of Hospitals, the American Medical Association Census of Medical Groups, the InterStudy National HMO Census, and the US County Business Patterns. Changes in the number and percentage of physicians in a particular specialty population from 1985 to 1994 were regressed, respectively, on 1985-94 changes in the explanatory variables as well as their levels in 1985. The results indicate that the population ecology framework is useful in explaining dynamics of change in the local physician workforce. Variables measuring the three environmental dimensions were found to have significant, and in some cases, differential effects on change in the size of different specialty populations. For example, both hospital consolidation and managed care penetration showed significant positive eflects on growth of the generalist population but suppressing effects on growth of the specialist population. The percentage of physicians in a particular specialty population in 1985 was negatively related to change in the size of that specialty population between 1985 and 1994, suggesting the existence of competition. Overall, the findings of this study facilitate a better understanding of the complexity of physician workforce supply.

Population estimates of extended family structure and size.

PubMed

Garceau, Anne; Wideroff, Louise; McNeel, Timothy; Dunn, Marsha; Graubard, Barry I

2008-01-01

Population-based estimates of biological family size can be useful for planning genetic studies, assessing how distributions of relatives affect disease associations with family history and estimating prevalence of potential family support. Mean family size per person is estimated from a population-based telephone survey (n = 1,019). After multivariate adjustment for demographic variables, older and non-White respondents reported greater mean numbers of total, first- and second-degree relatives. Females reported more total and first-degree relatives, while less educated respondents reported more second-degree relatives. Demographic differences in family size have implications for genetic research. Therefore, periodic collection of family structure data in representative populations would be useful. Copyright 2008 S. Karger AG, Basel.

Population structure of Angiostrongylus cantonensis (Nematoda: Metastrongylidae) in Thailand based on PCR-RAPD markers.

PubMed

Thaenkham, Urusa; Pakdee, Wallop; Nuamtanong, Supaporn; Maipanich, Wanna; Pubampen, Somchit; Sa-Nguankiat, Surapol; Komalamisra, Chalit

2012-05-01

Angiostrongylus cantonensis is the causative agent of angiostrongyliasis, which is widely distributed throughout the world. It can specifically infect many species of intermediate and definitive hosts. This study examined the genetic differentiation and population structure using the RAPD-PCR method of parasites obtained from 8 different geographical areas of Thailand. Based on 8 primers, high levels of genetic diversity and low levels of gene flow among populations were found. Using genetic distance and neighbor-joining dendrogram methods, A. cantonensis in Thailand could be divided into two groups with statistically significant genetic differentiation of the two populations. However, genotypic variations and haplotype relationships need to be further elucidated using other markers.

Strategic conservation of orchard germplasm based on indigenous knowledge and genetic diversity: a case study of sour orange populations in China.

PubMed

Ming, Feng; Liu, Qi-Kun; Shi, Jin-Lei; Wang, Wei; Lu, Bao-Rong

2009-01-01

To effectively conserve sour orange (Citrus aurantium L.) germplasm on two islands at the estuary of the Yangtze River in China, we estimated genetic variation and relationships of the known parental trees and their proposed descendents (young trees) using the fingerprints of random amplified polymorphic DNA (RAPD). Results based on RAPD analyses showed considerable genetic diversity in the parental populations (H(e)=0.202). The overall populations including the parental and young trees showed slightly higher genetic diversity (H(e)=0.298) than the parents, with about 10% variation between populations. An unweighted pair group method with arithmetic mean analysis dendrogram based on cluster analysis of the Jaccard similarity among individuals demonstrated a more complicated relationship of the parental and young trees from the two islands, although the young trees showed a clear association with parental trees. This indicates a significant contribution of parental trees in establishing the sour orange populations on the two islands. According to farmers' knowledge, conservation of only one or two parental trees would be sufficient because they believed that the whole populations were generated from a single mother tree. However, this study suggests that preserving most parental trees and some selected young trees with distant genetic relationships should be an effective conservation strategy for sour orange germplasm on the two islands.

First report of pyrethroid resistance in Rhipicephalus (Boophilus) annulatus larvae (Say, 1821) from Iran.

PubMed

Ziapour, Seyyed Payman; Kheiri, Sadegh; Asgarian, Fatemeh; Fazeli-Dinan, Mahmoud; Yazdi, Fariborz; Mohammadpour, Reza Ali; Aarabi, Mohsen; Enayati, Ahmadali

2016-04-01

Rhipicephalus (Boophilus) annulatus is one of the most important hard ticks parasitizing cattle in northern Iran. The aim of this study was to evaluate pyrethroid resistance levels of this species from Nur County, northern Iran. The hard ticks were collected through a multistage cluster randomized sampling method from the study area and fully engorged female R. (B.) annulatus were reared in a controlled insectary until they produced larvae for bioassay. Seventeen populations of the hard ticks were bioassayed with cypermethrin and 12 populations with lambda-cyhalothrin using a modified larval packet test (LPT). Biochemical assays to measure the contents/activity of different enzyme groups including mixed function oxidases (MFOs), glutathione S-transferases (GSTs) and general esterases were performed. Population 75 showed a resistance ratio of 4.05 with cypermethrin when compared with the most susceptible field population 66 at the LC50 level. With lambda-cyhalothrin the resistance ratio based on LC50 was 3.67 when compared with the susceptible population. The results of biochemical assays demonstrated significantly elevated levels of GSTs and esterases in populations tested compared with the heterozygous susceptible filed population and a correlation coefficient of these enzymes was found in association to lambda-cyhalothrin resistance. Based on the results, pyrethroid acaricides may operationally fail to control R. (B.) annulatus in North of Iran. This study is the first document of pyrethroid resistance in R. (B.) annulatus populations from Iran. Copyright © 2016 Elsevier B.V. All rights reserved.

Challenges of DNA-based mark-recapture studies of American black bears

USGS Publications Warehouse

Settlage, K.E.; Van Manen, F.T.; Clark, J.D.; King, T.L.

2008-01-01

We explored whether genetic sampling would be feasible to provide a region-wide population estimate for American black bears (Ursus americanus) in the southern Appalachians, USA. Specifically, we determined whether adequate capture probabilities (p >0.20) and population estimates with a low coefficient of variation (CV <20%) could be achieved given typical agency budget and personnel constraints. We extracted DNA from hair collected from baited barbed-wire enclosures sampled over a 10-week period on 2 study areas: a high-density black bear population in a portion of Great Smoky Mountains National Park and a lower density population on National Forest lands in North Carolina, South Carolina, and Georgia. We identified individual bears by their unique genotypes obtained from 9 microsatellite loci. We sampled 129 and 60 different bears in the National Park and National Forest study areas, respectively, and applied closed mark–recapture models to estimate population abundance. Capture probabilities and precision of the population estimates were acceptable only for sampling scenarios for which we pooled weekly sampling periods. We detected capture heterogeneity biases, probably because of inadequate spatial coverage by the hair-trapping grid. The logistical challenges of establishing and checking a sufficiently high density of hair traps make DNA-based estimates of black bears impractical for the southern Appalachian region. Alternatives are to estimate population size for smaller areas, estimate population growth rates or survival using mark–recapture methods, or use independent marking and recapturing techniques to reduce capture heterogeneity.

US EPA Base Study Standard Operating Procedure for Building Recruiting

EPA Pesticide Factsheets

Building recruiting for the BASE study is defined by a random selection of buildings within cities of population exceeding 100,000 inhabitants and located in selected climatic regions of the United States.

Practical Considerations when Using Pedometers to Assess Physical Activity in Population Studies: Lessons from the Burnie Take Heart Study

ERIC Educational Resources Information Center

Schmidt, Michael D.; Blizzard, C. Leigh; Venn, Alison J.; Cochrane, Jennifer A.; Dwyer, Terence

2007-01-01

The aim of this study was to summarize both practical and methodological issues in using pedometers to assess physical activity in a large epidemiologic study. As part of a population-based survey of cardiovascular disease risk factors, physical activity was assessed using pedometers and activity diaries in 775 men and women ages 25-64 years who…

Prevalence, Employment Rate, and Cost of Schizophrenia in a High-Income Welfare Society: A Population-Based Study Using Comprehensive Health and Welfare Registers

PubMed Central

Evensen, Stig; Wisløff, Torbjørn; Lystad, June Ullevoldsæter; Bull, Helen; Ueland, Torill; Falkum, Erik

2016-01-01

Schizophrenia is associated with recurrent hospitalizations, need for long-term community support, poor social functioning, and low employment rates. Despite the wide- ranging financial and social burdens associated with the illness, there is great uncertainty regarding prevalence, employment rates, and the societal costs of schizophrenia. The current study investigates 12-month prevalence of patients treated for schizophrenia, employment rates, and cost of schizophrenia using a population-based top-down approach. Data were obtained from comprehensive and mandatory health and welfare registers in Norway. We identified a 12-month prevalence of 0.17% for the entire population. The employment rate among working-age individuals was 10.24%. The societal costs for the 12-month period were USD 890 million. The average cost per individual with schizophrenia was USD 106 thousand. Inpatient care and lost productivity due to high unemployment represented 33% and 29%, respectively, of the total costs. The use of mandatory health and welfare registers enabled a unique and informative analysis on true population-based datasets. PMID:26433216

Mood disorder, anxiety, and suicide risk among subjects with alcohol abuse and/or dependence: a population-based study.

PubMed

Wiener, Carolina D; Moreira, Fernanda P; Zago, Alethea; Souza, Luciano M; Branco, Jeronimo C; Oliveira, Jacqueline F de; Silva, Ricardo A da; Portela, Luis V; Lara, Diogo R; Jansen, Karen; Oses, Jean P

2018-01-01

To evaluate the prevalence of alcohol abuse and/or dependence in a population-based sample of young adults and assess the prevalence of comorbid mood disorders, anxiety, and suicide risk in this population. This cross-sectional, population-based study enrolled 1,953 young adults aged 18-35 years. The CAGE questionnaire was used to screen for alcohol abuse and/or dependence, with CAGE scores ≥ 2 considered positive. Psychiatric disorders were investigated through the structured Mini International Neuropsychiatric Interview (MINI). Alcohol abuse and/or dependence was identified in 187 (9.60%) individuals (5.10% among women and 15.20% among men). Alcohol abuse and/or dependence were more prevalent among men than women, as well as among those who used tobacco, illicit drugs or presented with anxiety disorder, mood disorder, and suicide risk. These findings suggest that alcohol abuse and/or dependence are consistently associated with a higher prevalence of psychiatric comorbidities, could be considered important predictors of other psychiatric disorders, and deserve greater public heath attention, pointing to the need for alcohol abuse prevention programs.

Determinants of change in polypharmacy status in Switzerland: the population-based CoLaus study.

PubMed

Abolhassani, Nazanin; Castioni, Julien; Marques-Vidal, Pedro; Vollenweider, Peter; Waeber, Gérard

2017-09-01

This study aimed to assess the prevalence, the change, and the determinants of change in polypharmacy in a population-based sample. Baseline (2003-2006) and follow-up (2009-2012) data are from 4679 participants aged between 35 and 75 years (53.5% women, mean age 52.6 ± 10.6 years) from the population of Lausanne, Switzerland. Polypharmacy was defined by the regular use of ≥5 drugs. Four categories of change were defined: never (no polypharmacy at baseline and follow-up), initiating (no polypharmacy at baseline but at follow-up), maintaining, or quitting. Polypharmacy increased from 7.7% at baseline to 15.3% at follow-up. Cardiovascular drugs were the most prescribed medicines at baseline and follow-up. Gender, age, obesity, smoking, previously diagnosed hypertension, or diabetes or dyslipidemia were significantly and independently associated with initiating and maintaining polypharmacy. In a population-based sample, prevalence of polypharmacy doubled over a 5.6-year period. The main determinants of initiating polypharmacy were age, overweight and obesity, smoking status, and previously diagnosed cardiovascular risk factors.

Population-Based Assessment of Exposure to Risk Behaviors in Motion Pictures.

PubMed

Sargent, James D; Worth, Keilah A; Beach, Michael; Gerrard, Meg; Heatherton, Todd F

2008-01-01

The aim of most population-based studies of media is to relate a specific exposure to an outcome of interest. A research program has been developed that evaluates exposure to different components of movies in an attempt of assess the association of such exposure with the adoption of substance use during adolescence. To assess exposure to movie substance use, one must measure both viewing time and content. In developing the exposure measure, the study team was interested in circumventing a common problem in exposure measurement, where measures often conflate exposure to media with attention to media. Our aim in this paper is to present a validated measure of exposure to entertainment media, the Beach method, which combines recognition of a movie title with content analysis of the movie for substance use, to generate population based measures of exposure to substance use in this form of entertainment.

Population-Based Assessment of Exposure to Risk Behaviors in Motion Pictures

PubMed Central

Sargent, James D.; Worth, Keilah A.; Beach, Michael; Gerrard, Meg; Heatherton, Todd F.

2008-01-01

The aim of most population-based studies of media is to relate a specific exposure to an outcome of interest. A research program has been developed that evaluates exposure to different components of movies in an attempt of assess the association of such exposure with the adoption of substance use during adolescence. To assess exposure to movie substance use, one must measure both viewing time and content. In developing the exposure measure, the study team was interested in circumventing a common problem in exposure measurement, where measures often conflate exposure to media with attention to media. Our aim in this paper is to present a validated measure of exposure to entertainment media, the Beach method, which combines recognition of a movie title with content analysis of the movie for substance use, to generate population based measures of exposure to substance use in this form of entertainment. PMID:19122801

Modeling the population dynamics of Pacific yew.

Treesearch

Richard T. Busing; Thomas A. Spies

1995-01-01

A study of Pacific yew (Taxus brevifolia Nutt.) population dynamics in the mountains of western Oregon and Washington was based on a combination of long-term population data and computer modeling. Rates of growth and mortality were low in mature and old-growth forest stands. Diameter growth at breast height ranged from 0 to 3 centimeters per decade...

Population Size and Suicide in U.S. Cities: A Static and Dynamic Exploration

ERIC Educational Resources Information Center

McCall, Patricia L.; Tittle, Charles R.

2007-01-01

The relationship between city population size and suicide rates rarely has been examined directly, though scholars often assume such a relationship exists based on studies of the association between suicide rates and urbanization (percent of the population living in cities) in various social contexts. In an effort to determine the basic…

Blood Cadmium Levels and Incident Cardiovascular Events during Follow-up in a Population-Based Cohort of Swedish Adults: The Malmö Diet and Cancer Study

PubMed Central

Barregard, Lars; Sallsten, Gerd; Fagerberg, Björn; Borné, Yan; Persson, Margaretha; Hedblad, Bo; Engström, Gunnar

2015-01-01

Background: Cadmium exposure may increase the risk of cardiovascular disease. The only published longitudinal study on cadmium and incident cardiovascular disease was performed in American Indians with relatively high cadmium exposure. Objectives: Our aim was to examine the association between blood cadmium at baseline and incident cardiovascular events in a population-based study of Swedish men and women with cadmium levels similar to those of most European and U.S. populations. Methods: A Swedish population-based cohort (n = 6,103, age 46–67 years) was recruited between 1991 and 1994. After we excluded those with missing data on smoking, 4,819 participants remained. Acute coronary events, other major cardiac events, stroke, and cardiovascular mortality were followed until 2010. Associations with blood cadmium (estimated from cadmium in erythrocytes) were analyzed using Cox proportional hazards regression including potential confounders and important cardiovascular risk factors. Results: Hazard ratios for all cardiovascular end points were consistently increased for participants in the 4th blood cadmium quartile (median, 0.99 μg/L). In models that also included sex, smoking, waist circumference, education, physical activity, alcohol intake, serum triglycerides, HbA1c, and C-reactive protein, the hazard ratios comparing the highest and lowest quartiles of exposure were 1.8 (95% CI: 1.2, 2.7) for acute coronary events, and 1.9 (1.3, 2.9) for stroke. Hazard ratios in never-smokers were consistent with these estimates. Conclusions: Blood cadmium in the highest quartile was associated with incident cardiovascular disease and mortality in our population-based samples of Swedish adults. The consistent results among never-smokers are important because smoking is a strong confounder. Our findings suggest that measures to reduce cadmium exposures are warranted, even in populations without unusual sources of exposure. Citation: Barregard L, Sallsten G, Fagerberg B, Borné Y, Persson M, Hedblad B, Engström G. 2016. Blood cadmium levels and incident cardiovascular events during follow-up in a population-based cohort of Swedish adults: the Malmö Diet and Cancer Study. Environ Health Perspect 124:594–600; http://dx.doi.org/10.1289/ehp.1509735 PMID:26517380

Prevalence and Factors Associated with the Use of Eye Care Services in South Korea: Korea National Health and Nutrition Examination Survey 2010-2012.

PubMed

Park, Yong Seok; Heo, Hwan; Ye, Byeong Jin; Suh, Young-Woo; Kim, Seung-Hyun; Park, Shin Hae; Lim, Key Hwan; Lee, Sung Jin; Park, Song Hee; Baek, Seung-Hee

2017-02-01

To estimate the factors and prevalence of eye care service utilization in the South Korean population. This cross-sectional, population-based study included data from 22,550 Koreans aged ≥5 years who participated in the Korea National Health and Nutrition Examination Survey from 2010 to 2012. For people aged 5 to 11 years (young children), information was based on self-reports of contact with eye care service in the past year; for people aged ≥12 years (older population), the information was based on the self-reported lifetime contact with eye care service. Univariate and multivariate logistic regression analyses of the complex sample survey data were performed. The prevalence of eye care service use in young children during the past year was 61.1% (95% confidence interval, 58.1%-64.1%), while that in the older population during their lifetime was 73.5%. Subjects aged 7 to 11 years were more likely to have had an eye examination in the past year than subjects aged 5 to 6 years (odds ratio, 3.83; 95% confidence interval, 2.37-6.19). Multivariate logistic regression analysis indicated that higher monthly household income, being a National Health Insurance holder, and having private health insurance were related to more frequent use of eye care services in young children. For the older population and women, those living in an urban area and those with a best-corrected visual acuity less than 20 / 40 in the worse-seeing eye were more likely to have had an eye examination during their lifetime. Low education level was associated with low lifetime use of eye care services in the older population. There are sociodemographic disparities with use of eye care services in South Korea. This population-based study provides information that is useful for determining different intervention programs based on sociodemographic disparities to promote eye care service utilization in South Korea.

Epidemiology of amyotrophic lateral sclerosis in Minnesota: a year-long population based study.

PubMed

Harper, Caitlin J; Sorenson, Eric J; Mandrekar, Jay

2015-01-01

This is the largest population based study of ALS in the U.S., encompassing the population of Minnesota (> 5.4 million people) from July 2013 to July 2014. Data on gender, age at diagnosis, and residential county were collected for all Minnesota residents who registered with the Minnesota/North Dakota/South Dakota chapter of the ALS Association from July 2013 to July 2014. Incidence rates were calculated as the number of new cases of ALS per 100,000 people per year. The standardized incidence rates for the 2013 U.S. population and the 2013 European standard population were also reported. Results showed that the crude incidence rate of ALS was 2.2 cases per 100,000 person-years. Incidence increased with age, peaking at 70-79 years (8.3 per 100,000) with mean age at diagnosis 64 years, and was greater in males (2.4 per 100,000) than in females (1.5 per 100,000). Standardized incidence rates for the 2013 U.S. and European standard population were 2.2 and 2.39 cases per 100,000 person-years, respectively. In conclusion, the overall incidence and age and gender patterns of ALS in Minnesota are comparable to those reported by European studies ( 1-5 ).

Cardiopulmonary resuscitation of out-of-hospital traumatic cardiac arrest in Qatar: A nationwide population-based study.

PubMed

Irfan, Furqan B; Consunji, Rafael; El-Menyar, Ayman; George, Pooja; Peralta, Ruben; Al-Thani, Hassan; Thomas, Stephen Hodges; Alinier, Guillaume; Shuaib, Ashfaq; Al-Suwaidi, Jassim; Singh, Rajvir; Castren, Maaret; Cameron, Peter A; Djarv, Therese

2017-08-01

Traumatic cardiac arrest studies have reported improved survival rates recently, ranging from 1.7-7.5%. This population-based nationwide study aims to describe the epidemiology, interventions and outcomes, and determine predictors of survival from out-of-hospital traumatic cardiac arrest (OHTCA) in Qatar. An observational retrospective population-based study was conducted on OHTCA patients in Qatar, from January 2010 to December 2015. Traumatic cardiac arrest was redefined to include out-of-hospital traumatic cardiac arrest (OHTCA) and in-hospital traumatic cardiac arrest (IHTCA). A total of 410 OHTCA patients were included in the 6-year study period. The mean annual crude incidence rate of OHTCA was 4.0 per 100,000 population, in Qatar. OHTCA mostly occurred in males with a median age of 33. There was a preponderance of blunt injuries (94.3%) and head injuries (66.3%). Overall, the survival rate was 2.4%. Shockable rhythm, prehospital external hemorrhage control, in-hospital blood transfusion, and surgery were associated with higher odds of survival. Adrenaline (Epinephrine) lowered the odds of survival. The incidence of OHTCA was less than expected, with a low rate of survival. Thoracotomy was not associated with improved survival while Adrenaline administration lowered survival in OHTCA patients with majority blunt injuries. Interventions to enable early prehospital control of hemorrhage, blood transfusion, thoracostomy and surgery improved survival. Copyright © 2017 Elsevier B.V. All rights reserved.

The Relational-Behavior Model: A Pilot Assessment Study for At-Risk College Populations

ERIC Educational Resources Information Center

Chandler, Donald S., Jr.; Perkins, Michele D.

2007-01-01

This pilot study examined the relational-behavior model (RBM) as an HIV/AIDS assessment tool for at-risk college populations. Based on this theory, a survey was constructed to assess the six areas associated with HIV/AIDS prevention: personal awareness, knowledge deficiency, relational skills, HIV/STD stigmatization, community awareness, and…

Primary Prevention With Statins: ACC/AHA Risk-Based Approach Versus Trial-Based Approaches to Guide Statin Therapy.

PubMed

Mortensen, Martin B; Afzal, Shoaib; Nordestgaard, Børge G; Falk, Erling

2015-12-22

Guidelines recommend initiating primary prevention for atherosclerotic cardiovascular disease (ASCVD) with statins based on absolute ASCVD risk assessment. Recently, alternative trial-based and hybrid approaches were suggested for statin treatment eligibility. This study compared these approaches in a direct head-to-head fashion in a contemporary population. The study used the CGPS (Copenhagen General Population Study) with 37,892 subjects aged 40 to 75 years recruited in 2003 to 2008, all free of ASCVD, diabetes, and statin use at baseline. Among the population studied, 42% were eligible for statin therapy according to the 2013 American College of Cardiology/American Heart Association (ACC/AHA) risk assessment and cholesterol treatment guidelines approach, versus 56% with the trial-based approach and 21% with the hybrid approach. Among these statin-eligible subjects, the ASCVD event rate per 1,000 person-years was 9.8, 6.8, and 11.2, respectively. The ACC/AHA-recommended absolute risk score was well calibrated around the 7.5% 10-year ASCVD risk treatment threshold and discriminated better than the trial-based or hybrid approaches. Compared with the ACC/AHA risk-based approach, the net reclassification index for eligibility for statin therapy among 40- to 75-year-old subjects from the CGPS was -0.21 for the trial-based approach and -0.13 for the hybrid approach. The clinical performance of the ACC/AHA risk-based approach for primary prevention of ASCVD with statins was superior to the trial-based and hybrid approaches. Our results indicate that the ACC/AHA guidelines will prevent more ASCVD events than the trial-based and hybrid approaches, while treating fewer people compared with the trial-based approach. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Is hidradenitis suppurativa associated with anaemia?: a population-based and hospital-based cross-sectional study from Denmark.

PubMed

Miller, I M; Johansen, M E; Mogensen, U B; Zarchi, K; Ellervik, C; Jemec, G B

2016-08-01

Chronic inflammatory diseases may be associated with anaemia of inflammation. Hidradenitis suppurativa is a chronic inflammatory dermatological disease associated with metabolic comorbidities, low quality of life and fatigue. Anaemia may cause fatigue, and it has been hypothesized that HS-related fatigue may be partly due to anaemia. Our objective was to investigate a possible association between HS and anaemia. We performed a hospital-based and population-based cross-sectional study investigating the red blood cell profile, i.e. haemoglobin. We identified a total of 32 hospital HS individuals, 430 population HS individuals and 20,780 population non-HS control individuals. The age-sex-smoking-adjusted analyses showed no differences in the haemoglobin level of the HS groups vs. the control group. Analyses of the anaemic subgroup of HS individuals revealed that 60% had normocytic anaemia and 40% microcytic anaemia, in concordance with anaemia of inflammation. In contrast to our hypothesis, this study showed that HS is not associated with anaemia. Thus, anaemia may not be the cause of the described fatigue in HS patients. Furthermore, the results indicate that if an HS patient does suffer from anaemia it is most likely to be normocytic or microcytic and thus compatible with anaemia seen in other chronic inflammatory disorders. © 2015 European Academy of Dermatology and Venereology.

Triceps and Subscapular Skinfold Thickness Percentiles and Cut-Offs for Overweight and Obesity in a Population-Based Sample of Schoolchildren and Adolescents in Bogota, Colombia.

PubMed

Ramírez-Vélez, Robinson; López-Cifuentes, Mario Ferney; Correa-Bautista, Jorge Enrique; González-Ruíz, Katherine; González-Jiménez, Emilio; Córdoba-Rodríguez, Diana Paola; Vivas, Andrés; Triana-Reina, Hector Reynaldo; Schmidt-RioValle, Jacqueline

2016-09-24

The assessment of skinfold thickness is an objective measure of adiposity. The aims of this study were to establish Colombian smoothed centile charts and LMS L (Box-Cox transformation), M (median), and S (coefficient of variation) tables for triceps, subscapular, and triceps + subscapular skinfolds; appropriate cut-offs were selected using receiver operating characteristic (ROC) analysis based on a population-based sample of children and adolescents in Bogotá, Colombia. A cross-sectional study was conducted in 9618 children and adolescents (55.7% girls; age range of 9-17.9 years). Triceps and subscapular skinfold measurements were obtained using standardized methods. We calculated the triceps + subscapular skinfold (T + SS) sum. Smoothed percentile curves for triceps and subscapular skinfold thickness were derived using the LMS method. ROC curve analyses were used to evaluate the optimal cut-off point of skinfold thickness for overweight and obesity, based on the International Obesity Task Force definitions. Subscapular and triceps skinfolds and T + SS were significantly higher in girls than in boys (p < 0.001). The ROC analysis showed that subscapular and triceps skinfolds and T + SS have a high discriminatory power in the identification of overweight and obesity in the sample population in this study. Our results provide sex- and age-specific normative reference standards for skinfold thickness values from a population from Bogotá, Colombia.

Cross-cultural comparisons of attitudes toward schizophrenia amongst the general population and physicians: a series of web-based surveys in Japan and the United States.

PubMed

Richards, Misty; Hori, Hiroaki; Sartorius, Norman; Kunugi, Hiroshi

2014-02-28

Cross-cultural differences in attitudes toward schizophrenia are suggested, while no studies have compared such attitudes between the United States and Japan. In our previous study in Japan (Hori et al., 2011), 197 subjects in the general population and 112 physicians (excluding psychiatrists) enrolled in a web-based survey using an Internet-based questionnaire format. Utilizing the identical web-based survey method in the United States, the present study enrolled 172 subjects in the general population and 45 physicians. Participants' attitudes toward schizophrenia were assessed with the English version of the 18-item questionnaire used in our previous Japanese survey. Using exploratory factor analysis, we identified four factors labeled "social distance," "belief of dangerousness," "underestimation of patients' abilities," and "skepticism regarding treatment." The two-way multivariate analysis of covariance on the four factors, with country and occupation as the between-subject factors and with potentially confounding demographic variables as the covariates, revealed that the general population in the US scored significantly lower than the Japanese counterparts on the factors "social distance" and "skepticism regarding treatment" and higher on "underestimation of patients' abilities." Our results suggest that culture may have an important role in shaping attitudes toward mental illness. Anti-stigma campaigns that target culture-specific biases are considered important. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

A population-based registry as a source of health indicators for rare diseases: the ten-year experience of the Veneto Region’s rare diseases registry

PubMed Central

2014-01-01

Background Although rare diseases have become a major public health issue, there is a paucity of population-based data on rare diseases. The aim of this epidemiological study was to provide descriptive figures referring to a sizable group of unrelated rare diseases. Methods Data from the rare diseases registry established in the Veneto Region of north-east Italy (population 4,900,000), referring to the years from 2002 to 2012, were analyzed. The registry is based on a web-based system accessed by different users. Cases are enrolled by two different sources: clinicians working at Centers of expertise officially designated to diagnose and care patients with rare diseases and health professionals working in the local health districts. Deaths of patients are monitored by Death Registry. Results So far, 19,547 patients with rare diseases have been registered, and 23% of them are pediatric cases. The overall raw prevalence of the rare diseases monitored in the population under study is 33.09 per 10,000 inhabitants (95% CI 32.56-33.62), whilst the overall incidence is 3.85 per 10,000 inhabitants (95% CI 3.67-4.03). The most commonly-recorded diagnoses belong to the following nosological groups: congenital malformations (Prevalence: 5.45/10,000), hematological diseases (4.83/10,000), ocular disorders (4.47/10,000), diseases of the nervous system (3.51/10,000), and metabolic disorders (2,95/10,000). Most of the deaths in the study population occur among pediatric patients with congenital malformations, and among adult cases with neurological diseases. Rare diseases of the central nervous system carry the highest fatality rate (71.36/1,000). Rare diseases explain 4.2% of general population Years of Life Lost (YLLs), comparing to 1.2% attributable to infectious diseases and 2.6% to diabetes mellitus. Conclusions Our estimates of the burden of rare diseases at population level confirm that these conditions are a relevant public health issue. Our snapshot of their epidemiology is important for public health planning purposes, going to show that population-based registries are useful tools for generating health indicators relating to a considerable number of rare diseases, rather than to specific conditions. PMID:24646171

Genome-wide association study reveals regions associated with gestation length in two pig populations.

PubMed

Hidalgo, A M; Lopes, M S; Harlizius, B; Bastiaansen, J W M

2016-04-01

Reproduction traits, such as gestation length (GLE), play an important role in dam line breeding in pigs. The objective of our study was to identify single nucleotide polymorphisms (SNPs) that are associated with GLE in two pig populations. Genotypes and deregressed breeding values were available for 2081 Dutch Landrace-based (DL) and 2301 Large White-based (LW) pigs. We identified two QTL regions for GLE, one in each population. For DL, three associated SNPs were detected in one QTL region spanning 0.52 Mbp on Sus scrofa chromosome (SSC) 2. For LW, four associated SNPs were detected in one region of 0.14 Mbp on SSC5. The region on SSC2 contains the heparin-binding EGF-like growth factor (HBEGF) gene, which promotes embryo implantation and has been described to be involved in embryo survival throughout gestation. The associated SNP can be used for marker-assisted selection in the studied populations, and further studies of the HBEGF gene are warranted to investigate its role in GLE. © 2015 Stichting International Foundation for Animal Genetics.

The population approach to falls injury prevention in older people: findings of a two community trial

PubMed Central

2010-01-01

Background There is a sound rationale for the population-based approach to falls injury prevention but there is currently insufficient evidence to advise governments and communities on how they can use population-based strategies to achieve desired reductions in the burden of falls-related injury. The aim of the study was to quantify the effectiveness of a streamlined (and thus potentially sustainable and cost-effective), population-based, multi-factorial falls injury prevention program for people over 60 years of age. Methods Population-based falls-prevention interventions were conducted at two geographically-defined and separate Australian sites: Wide Bay, Queensland, and Northern Rivers, NSW. Changes in the prevalence of key risk factors and changes in rates of injury outcomes within each community were compared before and after program implementation and changes in rates of injury outcomes in each community were also compared with the rates in their respective States. Results The interventions in neither community substantially decreased the rate of falls-related injury among people aged 60 years or older, although there was some evidence of reductions in occurrence of multiple falls reported by women. In addition, there was some indication of improvements in fall-related risk factors, but the magnitudes were generally modest. Conclusions The evidence suggests that low intensity population-based falls prevention programs may not be as effective as those that are intensively implemented. PMID:20167124

Coexisting Psychiatric Problems and Stressful Life Events in Adults with Symptoms of ADHD--A Large Swedish Population-Based Study of Twins

ERIC Educational Resources Information Center

Friedrichs, Bettina; Igl, Wilmar; Larsson, Henrik; Larsson, Jan-Olov

2012-01-01

Objective: To explore the associations of subtypes of adult ADHD with other psychiatric problems, stressful life events, and sex differences. Method: Odds ratios were calculated using information from 17,899 participants from a population-based survey of adult twins born in Sweden between 1959 and 1985. Results: Symptoms of attention deficit…

Clinical Validity of the ADI-R in a US-Based Latino Population

ERIC Educational Resources Information Center

Vanegas, Sandra B.; Magaña, Sandra; Morales, Miguel; McNamara, Ellyn

2016-01-01

The Autism Diagnostic Interview-Revised (ADI-R) has been validated as a tool to aid in the diagnosis of Autism; however, given the growing diversity in the United States, the ADI-R must be validated for different languages and cultures. This study evaluates the validity of the ADI-R in a US-based Latino, Spanish-speaking population of 50 children…

Whether the Autism Spectrum Quotient Consists of Two Different Subgroups? Cluster Analysis of the Autism Spectrum Quotient in General Population

ERIC Educational Resources Information Center

Kitazoe, Noriko; Fujita, Naofumi; Izumoto, Yuji; Terada, Shin-ichi; Hatakenaka, Yuhei

2017-01-01

The purpose of this study was to investigate whether the individuals in the general population with high scores on the Autism Spectrum Quotient constituted a single homogeneous group or not. A cohort of university students (n = 4901) was investigated by cluster analysis based on the original five subscales of the Autism Spectrum Quotient. Based on…

Sleep Problems in Children with Autism Spectrum Problems: A Longitudinal Population-Based Study

ERIC Educational Resources Information Center

Sivertsen, Borge; Posserud, Maj-Britt; Gillberg, Christopher; Lundervold, Astri J.; Hysing, Mari

2012-01-01

This study examined the prevalence and chronicity of sleep problems in children who manifest problems believed to be typical of Autism Spectrum Disorders (ASD). Using data from a longitudinal total population study, symptoms of ASD, insomnia and potential explanatory factors were assessed at ages 7-9 and 11-13. Children were included in a group…

Body Mass Index in Adults with Intellectual Disability: Distribution, Associations and Service Implications--A Population-Based Prevalence Study

ERIC Educational Resources Information Center

Bhaumik, S.; Watson, J. M.; Thorp, C. F.; Tyrer, F.; McGrother, C. W.

2008-01-01

Background: Previous studies of weight problems in adults with intellectual disability (ID) have generally been small or selective and given conflicting results. The objectives of our large-scale study were to identify inequalities in weight problems between adults with ID and the general adult population, and to investigate factors associated…

A Relationship between Early Language Skills and Adult Autistic-Like Traits: Evidence from a Longitudinal Population-Based Study

ERIC Educational Resources Information Center

Armstrong, Rebecca; Whitehouse, Andrew J. O.; Scott, James G.; Copland, David A.; McMahon, Katie L.; Fleming, Sophie; Arnott, Wendy

2017-01-01

The current study examined the relationship between early language ability and autistic-like traits in adulthood, utilising data from 644 participants from a longitudinal study of the general population. Language performance at 2 years was measured with the Language Development Survey (LDS), and at 20 years the participants completed the…

Paternal genetic affinity between western Austronesians and Daic populations

PubMed Central

2008-01-01

Background Austronesian is a linguistic family spread in most areas of the Southeast Asia, the Pacific Ocean, and the Indian Ocean. Based on their linguistic similarity, this linguistic family included Malayo-Polynesians and Taiwan aborigines. The linguistic similarity also led to the controversial hypothesis that Taiwan is the homeland of all the Malayo-Polynesians, a hypothesis that has been debated by ethnologists, linguists, archaeologists, and geneticists. It is well accepted that the Eastern Austronesians (Micronesians and Polynesians) derived from the Western Austronesians (Island Southeast Asians and Taiwanese), and that the Daic populations on the mainland are supposed to be the headstream of all the Austronesian populations. Results In this report, we studied 20 SNPs and 7 STRs in the non-recombining region of the 1,509 Y chromosomes from 30 China Daic populations, 23 Indonesian and Vietnam Malayo-Polynesian populations, and 11 Taiwan aboriginal populations. These three groups show many resemblances in paternal lineages. Admixture analyses demonstrated that the Daic populations are hardly influenced by Han Chinese genetically, and that they make up the largest proportion of Indonesians. Most of the population samples contain a high frequency of haplogroup O1a-M119, which is nearly absent in other ethnic families. The STR network of haplogroup O1a* illustrated that Indonesian lineages did not derive from Taiwan aborigines as linguistic studies suggest, but from Daic populations. Conclusion We show that, in contrast to the Taiwan homeland hypothesis, the Island Southeast Asians do not have a Taiwan origin based on their paternal lineages. Furthermore, we show that both Taiwan aborigines and Indonesians likely derived from the Daic populations based on their paternal lineages. These two populations seem to have evolved independently of each other. Our results indicate that a super-phylum, which includes Taiwan aborigines, Daic, and Malayo-Polynesians, is genetically educible. PMID:18482451

Postmating sexual selection: allopatric evolution of sperm competition mechanisms and genital morphology in calopterygid damselflies (Insecta: Odonata).

PubMed

Cordero Rivera, A; Andrés, J A; Córdoba-Aguilar, A; Utzeri, C

2004-02-01

Postmating sexual selection theory predicts that in allopatry reproductive traits diverge rapidly and that the resulting differentiation in these traits may lead to restrictions to gene flow between populations and, eventually, reproductive isolation. In this paper we explore the potential for this premise in a group of damselflies of the family Calopterygidae, in which postmating sexual mechanisms are especially well understood. Particularly, we tested if in allopatric populations the sperm competition mechanisms and genitalic traits involved in these mechanisms have indeed diverged as sexual selection theory predicts. We did so in two different steps. First, we compared the sperm competition mechanisms of two allopatric populations of Calopteryx haemorrhoidalis (one Italian population studied here and one Spanish population previously studied). Our results indicate that in both populations males are able to displace spermathecal sperm, but the mechanism used for sperm removal between both populations is strikingly different. In the Spanish population males seem to empty the spermathecae by stimulating females, whereas in the Italian population males physically remove sperm from the spermathecae. Both populations also exhibit differences in genital morphometry that explain the use of different mechanisms: the male lateral processes are narrower than the spermathecal ducts in the Italian population, which is the reverse in the Spanish population. The estimated degree of phenotypic differentiation between these populations based on the genitalic traits involved in sperm removal was much greater than the differentiation based on a set of other seven morphological variables, suggesting that strong directional postmating sexual selection is indeed the main evolutionary force behind the reproductive differentiation between the studied populations. In a second step, we examined if a similar pattern in genital morphometry emerge in allopatric populations of this and other three species of the same family (Calopteryx splendens, C. virgo and Hetaerina cruentata). Our results suggest that there is geographic variation in the sperm competition mechanisms in all four studied species. Furthermore, genitalic morphology was significantly divergent between populations within species even when different populations were using the same copulatory mechanism. These results can be explained by probable local coadaptation processes that have given rise to an ability or inability to reach and displace spermathecal sperm in different populations. This set of results provides the first direct evidence of intraspecific evolution of genitalic traits shaped by postmating sexual selection.

Absorption line indices in the UV. I. Empirical and theoretical stellar population models

NASA Astrophysics Data System (ADS)

Maraston, C.; Nieves Colmenárez, L.; Bender, R.; Thomas, D.

2009-01-01

Aims: Stellar absorption lines in the optical (e.g. the Lick system) have been extensively studied and constitute an important stellar population diagnostic for galaxies in the local universe and up to moderate redshifts. Proceeding towards higher look-back times, galaxies are younger and the ultraviolet becomes the relevant spectral region where the dominant stellar populations shine. A comprehensive study of ultraviolet absorption lines of stellar population models is however still lacking. With this in mind, we study absorption line indices in the far and mid-ultraviolet in order to determine age and metallicity indicators for UV-bright stellar populations in the local universe as well as at high redshift. Methods: We explore empirical and theoretical spectral libraries and use evolutionary population synthesis to compute synthetic line indices of stellar population models. From the empirical side, we exploit the IUE-low resolution library of stellar spectra and system of absorption lines, from which we derive analytical functions (fitting functions) describing the strength of stellar line indices as a function of gravity, temperature and metallicity. The fitting functions are entered into an evolutionary population synthesis code in order to compute the integrated line indices of stellar populations models. The same line indices are also directly evaluated on theoretical spectral energy distributions of stellar population models based on Kurucz high-resolution synthetic spectra, In order to select indices that can be used as age and/or metallicity indicators for distant galaxies and globular clusters, we compare the models to data of template globular clusters from the Magellanic Clouds with independently known ages and metallicities. Results: We provide synthetic line indices in the wavelength range ~1200 Å to ~3000 Å for stellar populations of various ages and metallicities.This adds several new indices to the already well-studied CIV and SiIV absorptions. Based on the comparison with globular cluster data, we select a set of 11 indices blueward of the 2000 Å rest-frame that allows us to recover well the ages and the metallicities of the clusters. These indices are ideal to study ages and metallicities of young galaxies at high redshift. We also provide the synthetic high-resolution stellar population SEDs.

[Blood component donors and recipients as linked study objects in epidemiological population-based surveys].

PubMed

Garmaeva, T Ts; Kulikov, S M

2015-01-01

A population of hematological cancer patients as recipients of many blood components and that of donors of blood components and bone marrow are related to the common event of contamination with viruses of blood-borne infections; which occurs and is detectable during long-term treatment and follow-up. They share interaction traits and diverse communication mechanisms, which call for complex interrelated trials in both groups with a mandatory epidemiological evidenced-based investigation of all cases of posttransfusion hepatitis B and/or C. The identity of infection with hepatitis B and C viruses, human immunodeficiency virus, and their association should be simultaneously studied in the populations of both donors and recipients of blood components and bone marrow.

Whole genome sequences are required to fully resolve the linkage disequilibrium structure of human populations.

PubMed

Pengelly, Reuben J; Tapper, William; Gibson, Jane; Knut, Marcin; Tearle, Rick; Collins, Andrew; Ennis, Sarah

2015-09-03

An understanding of linkage disequilibrium (LD) structures in the human genome underpins much of medical genetics and provides a basis for disease gene mapping and investigating biological mechanisms such as recombination and selection. Whole genome sequencing (WGS) provides the opportunity to determine LD structures at maximal resolution. We compare LD maps constructed from WGS data with LD maps produced from the array-based HapMap dataset, for representative European and African populations. WGS provides up to 5.7-fold greater SNP density than array-based data and achieves much greater resolution of LD structure, allowing for identification of up to 2.8-fold more regions of intense recombination. The absence of ascertainment bias in variant genotyping improves the population representativeness of the WGS maps, and highlights the extent of uncaptured variation using array genotyping methodologies. The complete capture of LD patterns using WGS allows for higher genome-wide association study (GWAS) power compared to array-based GWAS, with WGS also allowing for the analysis of rare variation. The impact of marker ascertainment issues in arrays has been greatest for Sub-Saharan African populations where larger sample sizes and substantially higher marker densities are required to fully resolve the LD structure. WGS provides the best possible resource for LD mapping due to the maximal marker density and lack of ascertainment bias. WGS LD maps provide a rich resource for medical and population genetics studies. The increasing availability of WGS data for large populations will allow for improved research utilising LD, such as GWAS and recombination biology studies.

Increased risk of pyogenic liver abscess in patients with alcohol intoxication: A population-based retrospective cohort study.

PubMed

Wang, Yao-Chien; Yang, Kai-Wei; Lee, Tien-Ying Peter; Lin, Cheng-Li; Liaw, Geng-Wang; Hung, Dong-Zong; Kao, Chia-Hung; Chen, Wei-Kung; Yang, Tse-Yen

2017-11-01

We designed a population-based retrospective cohort study to investigate the association between the event of alcohol intoxication and the risk of pyogenic liver abscess. The present study enrolled 245,076 patients with a history of alcohol intoxication from 2000 to 2010 and matched each of them with four comparison patients, with similar mean age and sex ratios. We determined the cumulative incidences and adjusted hazard ratios (aHRs) of liver abscess. A significant association was observed between alcohol intoxication and liver abscess. The incidence density rate of liver abscess was 3.47-fold greater in the alcohol intoxication (AI) cohort than in the non-AI cohort (12.2 vs. 3.43 per 10,000 person-years), with an adjusted HR (aHR) of 2.64 (95% CI = 2.26 to 3.08). This population-based study positively associated the event of alcohol intoxication with increased risk of liver abscess. Our findings warrant further large-scale and in-depth investigations in this area. Copyright © 2017 Elsevier Inc. All rights reserved.

Big Feet: Assessing the Current and Future Impact of Population Size on a Country's Ecological Footprint

NASA Astrophysics Data System (ADS)

Hogg, R. S.; Takaro, T.; Miller, C.; Hogg, E.; Anema, A.; Gislason, M.; Parkes, M.

2015-12-01

Background: Ecological footprints assess the land and water a population needs to procure its resources and handle its waste. Measures derived from these footprints look at a population's ecological overshoot rather than weighting the population to its footprint. The aim of this study was to examine the latter approach by determining what the current and future weighted world population, by income gradient, would be if everyone lived within the boundary of 1.8 hectares per person. Methods: Country-specific ecological footprints and populations for 2007 were obtained from the Global Footprint Network (www.footprintnetwork.org); and projected populations were collected from US Census Bureau (www.census.gov). Footprint growth to 2050 was based on a business as usual approach developed by Kitzes et al. in Phil. Trans. R. Soc. B (2008). Weighted population estimates were derived by multiplying actual population by the ratio of the country's footprint to overall boundary of 1.8 hectares per person. Results: The weighted global population increased by 2.4 billion people (37%) in 2007 based on our adjustment. High and middle-income country populations increased, by 242% and 10%, respectively, while low-income country populations decreased by 33%. The weighed global population in 2050 increased by 10.1 billion with the majority of this growth occurring in high-income countries -- 437% versus 67% and 9% respectively for medium and low-income countries. Conclusions: Our study showed that current and future global weighted demographic and ecological impact would be felt mainly in high-income countries even though actual population growth would occur mainly in low and middle-income countries.

Adapting Technological Interventions to Meet the Needs of Priority Populations.

PubMed

Linke, Sarah E; Larsen, Britta A; Marquez, Becky; Mendoza-Vasconez, Andrea; Marcus, Bess H

2016-01-01

Cardiovascular diseases (CVD) comprise the leading cause of mortality worldwide, accounting for 3 in 10 deaths. Individuals with certain risk factors, including tobacco use, obesity, low levels of physical activity, type 2 diabetes mellitus, racial/ethnic minority status and low socioeconomic status, experience higher rates of CVD and are, therefore, considered priority populations. Technological devices such as computers and smartphones are now routinely utilized in research studies aiming to prevent CVD and its risk factors, and they are also rampant in the public and private health sectors. Traditional health behavior interventions targeting these risk factors have been adapted for technology-based approaches. This review provides an overview of technology-based interventions conducted in these priority populations as well as the challenges and gaps to be addressed in future research. Researchers currently possess tremendous opportunities to engage in technology-based implementation and dissemination science to help spread evidence-based programs focusing on CVD risk factors in these and other priority populations. Copyright © 2016 Elsevier Inc. All rights reserved.

Variation of genetic diversity in a rapidly expanding population of the greater long-tailed hamster (Tscherskia triton) as revealed by microsatellites.

PubMed

Xu, Laixiang; Xue, Huiliang; Song, Mingjing; Zhao, Qinghua; Dong, Jingping; Liu, Juan; Guo, Yu; Xu, Tongqin; Cao, Xiaoping; Wang, Fusheng; Wang, Shuqing; Hao, Shushen; Yang, Hefang; Zhang, Zhibin

2013-01-01

Genetic diversity is essential for persistence of animal populations over both the short- and long-term. Previous studies suggest that genetic diversity may decrease with population decline due to genetic drift or inbreeding of small populations. For oscillating populations, there are some studies on the relationship between population density and genetic diversity, but these studies were based on short-term observation or in low-density phases. Evidence from rapidly expanding populations is lacking. In this study, genetic diversity of a rapidly expanding population of the Greater long-tailed hamsters during 1984-1990, in the Raoyang County of the North China Plain was studied using DNA microsatellite markers. Results show that genetic diversity was positively correlated with population density (as measured by % trap success), and the increase in population density was correlated with a decrease of genetic differentiation between the sub-population A and B. The genetic diversity tended to be higher in spring than in autumn. Variation in population density and genetic diversity are consistent between sub-population A and B. Such results suggest that dispersal is density- and season-dependent in a rapidly expanding population of the Greater long-tailed hamster. For typically solitary species, increasing population density can increase intra-specific attack, which is a driving force for dispersal. This situation is counterbalanced by decreasing population density caused by genetic drift or inbreeding as the result of small population size. Season is a major factor influencing population density and genetic diversity. Meanwhile, roads, used to be considered as geographical isolation, have less effect on genetic differentiation in a rapidly expanding population. Evidences suggest that gene flow (Nm) is positively correlated with population density, and it is significant higher in spring than that in autumn.

Smoking Cessation among Low-Socioeconomic Status and Disadvantaged Population Groups: A Systematic Review of Research Output.

PubMed

Courtney, Ryan J; Naicker, Sundresan; Shakeshaft, Anthony; Clare, Philip; Martire, Kristy A; Mattick, Richard P

2015-06-08

Smoking cessation research output should move beyond descriptive research of the health problem to testing interventions that can provide causal data and effective evidence-based solutions. This review examined the number and type of published smoking cessation studies conducted in low-socioeconomic status (low-SES) and disadvantaged population groups. A systematic database search was conducted for two time periods: 2000-2004 (TP1) and 2008-2012 (TP2). Publications that examined smoking cessation in a low-SES or disadvantaged population were coded by: population of interest; study type (reviews, non-data based publications, data-based publications (descriptive, measurement and intervention research)); and country. Intervention studies were coded in accordance with the Cochrane Effective Practice and Organisation of Care data collection checklist and use of biochemical verification of self-reported abstinence was assessed. 278 citations were included. Research output (i.e., all study types) had increased from TP1 27% to TP2 73% (χ²=73.13, p<0.001), however, the proportion of data-based research had not significantly increased from TP1 and TP2: descriptive (TP1=23% vs. TP2=33%) or intervention (TP1=77% vs. TP2=67%). The proportion of intervention studies adopting biochemical verification of self-reported abstinence had significantly decreased from TP1 to TP2 with an increased reliance on self-reported abstinence (TP1=12% vs. TP2=36%). The current research output is not ideal or optimal to decrease smoking rates. Research institutions, scholars and funding organisations should take heed to review findings when developing future research and policy.

The role of chemoprevention by selective cyclooxygenase-2 inhibitors in colorectal cancer patients - a population-based study

PubMed Central

2012-01-01

Background There are limited population-based studies focusing on the chemopreventive effects of selective cyclooxygenase-2 (COX-2) inhibitors against colorectal cancer. The purpose of this study is to assess the trends and dose–response effects of various medication possession ratios (MPR) of selective COX-2 inhibitor used for chemoprevention of colorectal cancer. Methods A population-based case–control study was conducted using the Taiwan Health Insurance Research Database (NHIRD). The study comprised 21,460 colorectal cancer patients and 79,331 controls. The conditional logistic regression was applied to estimate the odds ratios (ORs) for COX-2 inhibitors used for several durations (5 years, 3 years, 1 year, 6 months and 3 months) prior to the index date. Results In patients receiving selective COX-2 inhibitors, the OR was 0.51 (95% CI=0.29~0.90, p=0.021) for an estimated 5-year period in developing colorectal cancer. ORs showing significant protection effects were found in 10% of MPRs for 5-year, 3-year, and 1-year usage. Risk reduction against colorectal cancer by selective COX-2 inhibitors was observed as early as 6 months after usage. Conclusion Our results indicate that selective COX-2 inhibitors may reduce the development of colorectal cancer by at least 10% based on the MPRs evaluated. Given the limited number of clinical reports from general populations, our results add to the knowledge of chemopreventive effects of selective COX-2 inhibitors against cancer in individuals at no increased risk of colorectal cancer. PMID:23217168

Methylenetetrahydrofolate reductase polymorphisms and susceptibility to acute lymphoblastic leukemia in a Chinese population: a meta-analysis.

PubMed

Xiao, Yi; Deng, Tao-Ran; Su, Chang-Liang; Shang, Zhen

2014-01-01

Although many epidemiologic studies have investigated the methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and their association with acute lymphoblastic leukemia (ALL), definitive conclusions cannot be drawn. To clarify the effects of MTHFR polymorphisms on the risk of ALL, a meta-analysis was performed in a Chinese population. A computerized literature search was carried out in PubMed, the Chinese Biomedicine (CBM) database, China National Knowledge Infrastructure (CNKI) platform, and the Wanfang database (Chinese) to collect relevant articles. A total of 11 articles including 1,738 ALL cases and 2,438 controls were included in this meta-analysis. Overall, a significantly decreased association was found between the MTHFR C677T polymorphism and ALL risk when all studies in Chinese populations were pooled into the meta-analysis. In subgroup analyses stratified by age, ethnicity, and source of controls, the same results were observed in children, in population-based studies, and in people with no stated ethnicity. However, a significantly increased association was also found for MTHFR C677T in hospital-based studies, and for MTHFR A1298C in people with no stated ethnicity. Our results suggest that the MTHFR C677T and A1298C polymorphisms may be potential biomarkers for ALL risk in Chinese populations, and studies with a larger sample size and wider population spectrum are required before definitive conclusions can be drawn. © 2014 S. Karger GmbH, Freiburg.

An ancestry informative marker set for determining continental origin: validation and extension using human genome diversity panels

PubMed Central

Nassir, Rami; Kosoy, Roman; Tian, Chao; White, Phoebe A; Butler, Lesley M; Silva, Gabriel; Kittles, Rick; Alarcon-Riquelme, Marta E; Gregersen, Peter K; Belmont, John W; De La Vega, Francisco M; Seldin, Michael F

2009-01-01

Background Case-control genetic studies of complex human diseases can be confounded by population stratification. This issue can be addressed using panels of ancestry informative markers (AIMs) that can provide substantial population substructure information. Previously, we described a panel of 128 SNP AIMs that were designed as a tool for ascertaining the origins of subjects from Europe, Sub-Saharan Africa, Americas, and East Asia. Results In this study, genotypes from Human Genome Diversity Panel populations were used to further evaluate a 93 SNP AIM panel, a subset of the 128 AIMS set, for distinguishing continental origins. Using both model-based and relatively model-independent methods, we here confirm the ability of this AIM set to distinguish diverse population groups that were not previously evaluated. This study included multiple population groups from Oceana, South Asia, East Asia, Sub-Saharan Africa, North and South America, and Europe. In addition, the 93 AIM set provides population substructure information that can, for example, distinguish Arab and Ashkenazi from Northern European population groups and Pygmy from other Sub-Saharan African population groups. Conclusion These data provide additional support for using the 93 AIM set to efficiently identify continental subject groups for genetic studies, to identify study population outliers, and to control for admixture in association studies. PMID:19630973

Accounting for Population Structure in Gene-by-Environment Interactions in Genome-Wide Association Studies Using Mixed Models.

PubMed

Sul, Jae Hoon; Bilow, Michael; Yang, Wen-Yun; Kostem, Emrah; Furlotte, Nick; He, Dan; Eskin, Eleazar

2016-03-01

Although genome-wide association studies (GWASs) have discovered numerous novel genetic variants associated with many complex traits and diseases, those genetic variants typically explain only a small fraction of phenotypic variance. Factors that account for phenotypic variance include environmental factors and gene-by-environment interactions (GEIs). Recently, several studies have conducted genome-wide gene-by-environment association analyses and demonstrated important roles of GEIs in complex traits. One of the main challenges in these association studies is to control effects of population structure that may cause spurious associations. Many studies have analyzed how population structure influences statistics of genetic variants and developed several statistical approaches to correct for population structure. However, the impact of population structure on GEI statistics in GWASs has not been extensively studied and nor have there been methods designed to correct for population structure on GEI statistics. In this paper, we show both analytically and empirically that population structure may cause spurious GEIs and use both simulation and two GWAS datasets to support our finding. We propose a statistical approach based on mixed models to account for population structure on GEI statistics. We find that our approach effectively controls population structure on statistics for GEIs as well as for genetic variants.

[Epidemiological methods used in studies in the prevalence of Tourette syndrome].

PubMed

Stefanoff, Paweł; Mazurek, Jacek

2003-01-01

Tourette syndrome (TS) prevalence was studied since the early 80-ies. Its clinical course is characterised by co-occurrence of motor and vocal tics. Results of previous epidemiological studies were surprisingly divergent: the prevalence varied from 0.5 to 115 cases per 10,000 population. The disease previously recognised as extremely rare and severe is now considered as quite common, with often moderate course. Selected methods used in studies of TS prevalence and analysis of their possible impact on study results are presented. The studies were divided into 3 groups: studies of the hospitalised population, large-scale screenings and studies involving school population, basing on characteristic and size of population, methods of selection of subjects, diagnostic and screening methods used. Studies of the hospitalised population involved patients with most severe symptoms, in different age groups, different methods of final diagnosis confirmation were used. TS prevalence varied from 0.5 up to 15 cases per 10,000 population. Procedures used in large-scale screening studies made possible the elimination of potential selection bias. Large populations were studied using transparent and repetitive confirmation of diagnoses. Their validity was additionally checked in parallel validity studies. TS prevalence was in the range 4.3 to 10 cases per 10,000 population. The highest TS prevalence was obtained in studies involving schoolchildren. Data were gathered from multiple sources: from parents, teachers and children, as well as from classroom observation. Diagnoses were made by experienced clinicians. TS prevalence obtained in school population studies was between 36.2 up to 115 per 10,000 population.

The Effects of Cannabis Among Adults With Chronic Pain and an Overview of General Harms: A Systematic Review.

PubMed

Nugent, Shannon M; Morasco, Benjamin J; O'Neil, Maya E; Freeman, Michele; Low, Allison; Kondo, Karli; Elven, Camille; Zakher, Bernadette; Motu'apuaka, Makalapua; Paynter, Robin; Kansagara, Devan

2017-09-05

Cannabis is increasingly available for the treatment of chronic pain, yet its efficacy remains uncertain. To review the benefits of plant-based cannabis preparations for treating chronic pain in adults and the harms of cannabis use in chronic pain and general adult populations. MEDLINE, Cochrane Database of Systematic Reviews, and several other sources from database inception to March 2017. Intervention trials and observational studies, published in English, involving adults using plant-based cannabis preparations that reported pain, quality of life, or adverse effect outcomes. Two investigators independently abstracted study characteristics and assessed study quality, and the investigator group graded the overall strength of evidence using standard criteria. From 27 chronic pain trials, there is low-strength evidence that cannabis alleviates neuropathic pain but insufficient evidence in other pain populations. According to 11 systematic reviews and 32 primary studies, harms in general population studies include increased risk for motor vehicle accidents, psychotic symptoms, and short-term cognitive impairment. Although adverse pulmonary effects were not seen in younger populations, evidence on most other long-term physical harms, in heavy or long-term cannabis users, or in older populations is insufficient. Few methodologically rigorous trials; the cannabis formulations studied may not reflect commercially available products; and limited applicability to older, chronically ill populations and patients who use cannabis heavily. Limited evidence suggests that cannabis may alleviate neuropathic pain in some patients, but insufficient evidence exists for other types of chronic pain. Among general populations, limited evidence suggests that cannabis is associated with an increased risk for adverse mental health effects. U.S. Department of Veterans Affairs. (PROSPERO: CRD42016033623).

A Comparison of Educational Differences on Physical Health, Mortality, and Healthy Life Expectancy in Japan and the United States.

PubMed

Chiu, Chi-Tsun; Hayward, Mark; Saito, Yasuhiko

2016-10-01

This study examined the educational gradient of health and mortality between two long-lived populations: Japan and the United States. This analysis is based on the Nihon University Japanese Longitudinal Study of Aging and the Health and Retirement Study to compare educational gradients in multiple aspects of population health-life expectancy with/without disability, functional limitations, or chronic diseases, using prevalence-based Sullivan life tables. Our results show that education coefficients from physical health and mortality models are similar for both Japan and American populations, and older Japanese have better mortality and health profiles. Japan's compulsory national health service system since April 1961 and living arrangements with adult children may play an important role for its superior health profile compared with that of the United States. © The Author(s) 2016.

Factors associated with lower gait speed among the elderly living in a developing country: a cross-sectional population-based study.

PubMed

Busch, Telma de Almeida; Duarte, Yeda Aparecida; Pires Nunes, Daniella; Lebrão, Maria Lucia; Satya Naslavsky, Michel; dos Santos Rodrigues, Anelise; Amaro, Edson

2015-04-01

Among community-dwelling older adults, mean values for gait speed vary substantially depending not only on the population studied, but also on the methodology used. Despite the large number of studies published in developed countries, there are few population-based studies in developing countries with socioeconomic inequality and different health conditions, and this is the first study with a representative sample of population. To explore this, the association of lower gait speed with sociodemographic, anthropometric factors, mental status and physical health was incorporated participants' weight (main weight) in the analysis of population of community-dwelling older adults living in a developing country. This was a cross-sectional population based on a sample of 1112 older adults aged 60 years and over from Health, Wellbeing and Aging Study cohort 2010. Usual gait speed (s) to walk 3 meters was stratified by sex and height into quartiles. Multiple regression analysis was performed to investigate the independent effect of each factor associated with a slower usual gait speed. The average walking speed of the elderly was 0.81 m/s-0.78 m/s among women and 0.86 m/s among men. In the final model, the factors associated with lower gait speed were age (OR = 3.56), literacy (OR = 3.20), difficulty in one or more IADL (OR = 2.74), presence of cardiovascular disease (OR = 2.15) and sedentarism. When we consider the 50% slower, we can add the variables handgrip strength, and the presence of COPD. Gait speed is a clinical marker and an important measure of functional capacity among the elderly. Our findings suggest that lower walking speed is associated with age, education, but especially with modifiable factors such as impairment of IADL, physical inactivity and cardiovascular disease. These results reinforce how important it is for the elderly to remain active and healthy.

Medical science in Siberia: Oxygen exchange in the Far North

NASA Technical Reports Server (NTRS)

Kulikov, V.; Yegunova, M.

1979-01-01

Differences in oxygen conditions between the native and migrant Siberian population were studied in relation to respiratory function, arterial and venous blood indicators and acid-base indicators. Significant adaptation differences were ascertained between the two populations.

Invitation strategies and coverage in the population-based cancer screening programmes in the European Union.

PubMed

Vale, Diama B; Anttila, Ahti; Ponti, Antonio; Senore, Carlo; Sankaranaryanan, Rengaswamy; Ronco, Guglielmo; Segnan, Nereo; Tomatis, Mariano; Žakelj, Maja P; Elfström, Klara M; Lönnberg, Stefan; Dillner, Joakim; Basu, Partha

2018-03-21

The aim of this study was to describe the compliance of the population-based cancer screening programmes in the European Union Member States to the invitation strategies enumerated in the European Guidelines and the impact of such strategies on the invitational coverage. Experts in screening programme monitoring from the respective countries provided data. Coverage by invitation was calculated as the proportion of individuals in the target age range receiving a screening invitation over the total number of annualized eligible population. The invitation strategies of 30 breasts, 25 cervical and 27 colorectal national or regional population-based screening programmes are described. Individual mail invitations are sent by 28 breasts, 20 cervical and 25 colorectal screening programmes. Faecal occult blood test kits are sent by post in 17 of the colorectal cancer screening programmes. The majority of programmes claimed to have a population registry, although some use health insurance data as the database for sending invitations. At least 95% invitation coverage was reached by 16 breast, six cervical and five colorectal screening programmes. Majority of the programmes comply with the invitation strategies enumerated in the European guidelines, although there is still scope for improvements. Coverage by invitation is below the desirable level in many population-based cancer screening programmes in European Union.

The role of area-level deprivation and gender in participation in population-based faecal immunochemical test (FIT) colorectal cancer screening.

PubMed

Clarke, Nicholas; McNamara, Deirdre; Kearney, Patricia M; O'Morain, Colm A; Shearer, Nikki; Sharp, Linda

2016-12-01

This study aimed to investigate the effects of sex and deprivation on participation in a population-based faecal immunochemical test (FIT) colorectal cancer screening programme. The study population included 9785 individuals invited to participate in two rounds of a population-based biennial FIT-based screening programme, in a relatively deprived area of Dublin, Ireland. Explanatory variables included in the analysis were sex, deprivation category of area of residence and age (at end of screening). The primary outcome variable modelled was participation status in both rounds combined (with "participation" defined as having taken part in either or both rounds of screening). Poisson regression with a log link and robust error variance was used to estimate relative risks (RR) for participation. As a sensitivity analysis, data were stratified by screening round. In both the univariable and multivariable models deprivation was strongly associated with participation. Increasing affluence was associated with higher participation; participation was 26% higher in people resident in the most affluent compared to the most deprived areas (multivariable RR=1.26: 95% CI 1.21-1.30). Participation was significantly lower in males (multivariable RR=0.96: 95%CI 0.95-0.97) and generally increased with increasing age (trend per age group, multivariable RR=1.02: 95%CI, 1.01-1.02). No significant interactions between the explanatory variables were found. The effects of deprivation and sex were similar by screening round. Deprivation and male gender are independently associated with lower uptake of population-based FIT colorectal cancer screening, even in a relatively deprived setting. Development of evidence-based interventions to increase uptake in these disadvantaged groups is urgently required. Copyright © 2016. Published by Elsevier Inc.

Population-based assessment of vision-related quality of life in corneal disease: results from the CORE study.

PubMed

Vashist, Praveen; Gupta, Noopur; Tandon, Radhika; Gupta, Sanjeev K; Dwivedi, Sadanand; Mani, Kalaivani

2016-05-01

To assess the impact of corneal disease on vision-related quality of life (VR-QoL) in a rural North Indian population. Cross-sectional, population-based study. The Corneal Opacity Rural Epidemiological (CORE) study included 12 899 participants from 25 randomly selected clusters of rural Gurgaon, Haryana, India, with the primary objective of determining the prevalence of corneal disease in the general population during July 2011 to January 2013. VR-QoL was assessed through Indian Vision Function questionnaire (IND-VFQ-33) in adult participants (aged ≥18 years) detected with corneal opacity and equal number of healthy controls (no ocular pathology with visual acuity of 6/6 binocularly) selected from the same clusters. Scores of the three subscales of IND-VFQ-33 (vision-specific mobility, psychosocial impact and visual symptoms) were computed, analysed and compared separately across various groups. Overall, 12 113 participants of all ages underwent detailed ophthalmic examination and VR-QoL was assessed in 435 cases with corneal disease and 435 controls without any ophthalmic disease. The diseased population had significantly higher scores and hence poorer VR-QoL across all three domains of vision function (scores of 28 vs 22; 6 vs 5 and 14 vs 9, respectively; p<0.0001) and the scores were inversely related with the level of visual impairment in patients with corneal disease. Patients with unilateral corneal disease also had poorer VR-QoL scores as compared with healthy controls (p<0.0001). VR-QoL is impaired in patients with corneal disease, more so in patients with corneal blindness. This is the first population-based study to document VR-QoL through IND-VFQ-33 in the Indian population with corneal disease. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Temporal genetic stability of Stegomyia aegypti (= Aedes aegypti) populations.

PubMed

Gloria-Soria, A; Kellner, D A; Brown, J E; Gonzalez-Acosta, C; Kamgang, B; Lutwama, J; Powell, J R

2016-06-01

The mosquito Stegomyia aegypti (= Aedes aegypti) (Diptera: Culicidae) is the primary vector of viruses that cause yellow fever, dengue and Chikungunya fever. In the absence of effective vaccines, the reduction of these diseases relies on vector control strategies. The success of these strategies is tightly linked to the population dynamics of target populations. In the present study, 14 collections from St. aegypti populations separated by periods of 1-13 years were analysed to determine their temporal genetic stability. Although temporal structure is discernible in most populations, the degree of temporal differentiation is dependent on the population and does not obscure the geographic structure of the various populations. The results suggest that performing detailed studies in the years prior to and after population reduction- or modification-based control interventions at each target field site may be useful in assessing the probability of success. © 2016 The Royal Entomological Society.

Geographic and income variations in age at diagnosis and incidence of chronic myeloid leukemia.

PubMed

Mendizabal, Adam M; Younes, Naji; Levine, Paul H

2016-01-01

Developing countries have a younger population of CML patients than developed countries. Patterns of age at diagnosis and incidence by geography and gross national income (GNI) are not well understood. A population-based descriptive study was conducted using data from the International Agency for Research on Cancer's population-based registry compilation. Geographical regions were classified according to the United Nations World Macro Regions and Components. Age-Standardized Incidence Rates (ASR) were adjusted to the World Standard Population. Poisson regression was used to assess age-specific interactions. 57.2% were male among 33,690 diagnoses. Median age at diagnosis was lowest in Africa and Asia (47 years) and highest in Oceania (72 years). ASR was lowest in African males (0.61 per 100,000) and Asian females (0.55 per 100,000) and highest in Oceania males and females (1.78 and 0.96 per 100,000, respectively). A significant interaction (p < 0.0001) between age (<50 years and >50 years) and region exists; no significant differences were seen by region in the <50 age-group while significant differences by region exist in the >50 age group. Population-based estimates suggest that the median age at diagnosis and incidence varies by region. Geographic and income heterogeneity suggest an important effect of environment that warrants further studies.

Assessment of fracture risk: value of random population-based samples--the Geelong Osteoporosis Study.

PubMed

Henry, M J; Pasco, J A; Seeman, E; Nicholson, G C; Sanders, K M; Kotowicz, M A

2001-01-01

Fracture risk is determined by bone mineral density (BMD). The T-score, a measure of fracture risk, is the position of an individual's BMD in relation to a reference range. The aim of this study was to determine the magnitude of change in the T-score when different sampling techniques were used to produce the reference range. Reference ranges were derived from three samples, drawn from the same region: (1) an age-stratified population-based random sample, (2) unselected volunteers, and (3) a selected healthy subset of the population-based sample with no diseases or drugs known to affect bone. T-scores were calculated using the three reference ranges for a cohort of women who had sustained a fracture and as a group had a low mean BMD (ages 35-72 yr; n = 484). For most comparisons, the T-scores for the fracture cohort were more negative using the population reference range. The difference in T-scores reached 1.0 SD. The proportion of the fracture cohort classified as having osteoporosis at the spine was 26, 14, and 23% when the population, volunteer, and healthy reference ranges were applied, respectively. The use of inappropriate reference ranges results in substantial changes to T-scores and may lead to inappropriate management.

IBSEM: An Individual-Based Atlantic Salmon Population Model

PubMed Central

Castellani, Marco; Heino, Mikko; Gilbey, John; Araki, Hitoshi; Svåsand, Terje; Glover, Kevin A.

2015-01-01

Ecology and genetics can influence the fate of individuals and populations in multiple ways. However, to date, few studies consider them when modelling the evolutionary trajectory of populations faced with admixture with non-local populations. For the Atlantic salmon, a model incorporating these elements is urgently needed because many populations are challenged with gene-flow from non-local and domesticated conspecifics. We developed an Individual-Based Salmon Eco-genetic Model (IBSEM) to simulate the demographic and population genetic change of an Atlantic salmon population through its entire life-cycle. Processes such as growth, mortality, and maturation are simulated through stochastic procedures, which take into account environmental variables as well as the genotype of the individuals. IBSEM is based upon detailed empirical data from salmon biology, and parameterized to reproduce the environmental conditions and the characteristics of a wild population inhabiting a Norwegian river. Simulations demonstrated that the model consistently and reliably reproduces the characteristics of the population. Moreover, in absence of farmed escapees, the modelled populations reach an evolutionary equilibrium that is similar to our definition of a ‘wild’ genotype. We assessed the sensitivity of the model in the face of assumptions made on the fitness differences between farm and wild salmon, and evaluated the role of straying as a buffering mechanism against the intrusion of farm genes into wild populations. These results demonstrate that IBSEM is able to capture the evolutionary forces shaping the life history of wild salmon and is therefore able to model the response of populations under environmental and genetic stressors. PMID:26383256

Customized versus population-based birth weight charts for the detection of neonatal growth and perinatal morbidity in a cross-sectional study of term neonates.

PubMed

Carberry, Angela E; Raynes-Greenow, Camille H; Turner, Robin M; Jeffery, Heather E

2013-10-15

Customized birth weight charts that incorporate maternal characteristics are now being adopted into clinical practice. However, there is controversy surrounding the value of these charts in the prediction of growth and perinatal outcomes. The objective of this study was to assess the use of customized charts in predicting growth, defined by body fat percentage, and perinatal morbidity. A total of 581 term (≥37 weeks' gestation) neonates born in Sydney, Australia, in 2010 were included. Body fat percentage measurements were taken by using air displacement plethysmography. Objective composite measurements of perinatal morbidity were used to identify neonates who had poor outcomes; these data were extracted from medical records. The value of customized charts was assessed by calculating positive predictive values, negative predictive values, and odds ratios with 95% confidence intervals. Customized versus population-based charts did not improve the prediction of either low body fat percentage (59% vs. 66% positive predictive value and 87% vs. 89% negative predictive value, respectively) or high body fat percentage (48% vs. 53% positive predictive value and 90% vs. 89% negative predictive value, respectively). Customized charts were not better than population-based charts at predicting perinatal morbidity (for customized charts, odds ratio = 1.02, 95% confidence interval: 1.01, 1.04; for population-based charts, odds ratio = 1.03, 95% confidence interval: 1.01, 1.05) per percentile decrease in birth weight. Customized birth weight charts do not provide significant improvements over population-based charts in predicting neonatal growth and morbidity.

A population-based exposure assessment methodology for carbon monoxide: Development of a carbon monoxide passive sampler and occupational dosimeter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Apte, Michael G.

Two devices, an occupational carbon monoxide (CO) dosimeter (LOCD), and an indoor air quality (IAQ) passive sampler were developed for use in population-based CO exposure assessment studies. CO exposure is a serious public health problem in the U.S., causing both morbidity and mortality (lifetime mortality risk approximately 10{sup -4}). Sparse data from population-based CO exposure assessments indicate that approximately 10% of the U.S. population is exposed to CO above the national ambient air quality standard. No CO exposure measurement technology is presently available for affordable population-based CO exposure assessment studies. The LOCD and IAQ Passive Sampler were tested in themore » laboratory and field. The palladium-molybdenum based CO sensor was designed into a compact diffusion tube sampler that can be worn. Time-weighted-average (TWA) CO exposure of the device is quantified by a simple spectrophotometric measurement. The LOCD and IAQ Passive Sampler were tested over an exposure range of 40 to 700 ppm-hours and 200 to 4200 ppm-hours, respectively. Both devices were capable of measuring precisely (relative standard deviation <20%), with low bias (<10%). The LOCD was screened for interferences by temperature, humidity, and organic and inorganic gases. Temperature effects were small in the range of 10°C to 30°C. Humidity effects were low between 20% and 90% RH. Ethylene (200 ppm) caused a positive interference and nitric oxide (50 ppm) caused a negative response without the presence of CO but not with CO.« less

Population Health and Tailored Medical Care in the Home: the Roles of Home-Based Primary Care and Home-Based Palliative Care.

PubMed

Ritchie, Christine S; Leff, Bruce

2018-03-01

With the growth of value-based care, payers and health systems have begun to appreciate the need to provide enhanced services to homebound adults. Recent studies have shown that home-based medical services for this high-cost, high-need population reduce costs and improve outcomes. Home-based medical care services have two flavors that are related to historical context and specialty background-home-based primary care (HBPC) and home-based palliative care (HBPalC). Although the type of services provided by HBPC and HBPalC (together termed "home-based medical care") overlap, HBPC tends to encompass longitudinal and preventive care, while HBPalC often provides services for shorter durations focused more on distress management and goals of care clarification. Given workforce constraints and growing demand, both HBPC and HBPalC will benefit from working together within a population health framework-where HBPC provides care to all patients who have trouble accessing traditional office practices and where HBPalC offers adjunctive care to patients with high symptom burden and those who need assistance with goals clarification. Policy changes that support provision of medical care in the home, population health strategies that tailor home-based medical care to the specific needs of the patients and their caregivers, and educational initiatives to assure basic palliative care competence for all home-based medical providers will improve access and reduce illness burden to this important and underrecognized population. Copyright © 2017 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

Diagnosis of Dementia by Machine learning methods in Epidemiological studies: a pilot exploratory study from south India.

PubMed

Bhagyashree, Sheshadri Iyengar Raghavan; Nagaraj, Kiran; Prince, Martin; Fall, Caroline H D; Krishna, Murali

2018-01-01

There are limited data on the use of artificial intelligence methods for the diagnosis of dementia in epidemiological studies in low- and middle-income country (LMIC) settings. A culture and education fair battery of cognitive tests was developed and validated for population based studies in low- and middle-income countries including India by the 10/66 Dementia Research Group. We explored the machine learning methods based on the 10/66 battery of cognitive tests for the diagnosis of dementia based in a birth cohort study in South India. The data sets for 466 men and women for this study were obtained from the on-going Mysore Studies of Natal effect of Health and Ageing (MYNAH), in south India. The data sets included: demographics, performance on the 10/66 cognitive function tests, the 10/66 diagnosis of mental disorders and population based normative data for the 10/66 battery of cognitive function tests. Diagnosis of dementia from the rule based approach was compared against the 10/66 diagnosis of dementia. We have applied machine learning techniques to identify minimal number of the 10/66 cognitive function tests required for diagnosing dementia and derived an algorithm to improve the accuracy of dementia diagnosis. Of 466 subjects, 27 had 10/66 diagnosis of dementia, 19 of whom were correctly identified as having dementia by Jrip classification with 100% accuracy. This pilot exploratory study indicates that machine learning methods can help identify community dwelling older adults with 10/66 criterion diagnosis of dementia with good accuracy in a LMIC setting such as India. This should reduce the duration of the diagnostic assessment and make the process easier and quicker for clinicians, patients and will be useful for 'case' ascertainment in population based epidemiological studies.

Invited review: study design considerations for clinical research in veterinary radiology and radiation oncology.

PubMed

Scrivani, Peter V; Erb, Hollis N

2013-01-01

High quality clinical research is essential for advancing knowledge in the areas of veterinary radiology and radiation oncology. Types of clinical research studies may include experimental studies, method-comparison studies, and patient-based studies. Experimental studies explore issues relative to pathophysiology, patient safety, and treatment efficacy. Method-comparison studies evaluate agreement between techniques or between observers. Patient-based studies investigate naturally acquired disease and focus on questions asked in clinical practice that relate to individuals or populations (e.g., risk, accuracy, or prognosis). Careful preplanning and study design are essential in order to achieve valid results. A key point to planning studies is ensuring that the design is tailored to the study objectives. Good design includes a comprehensive literature review, asking suitable questions, selecting the proper sample population, collecting the appropriate data, performing the correct statistical analyses, and drawing conclusions supported by the available evidence. Most study designs are classified by whether they are experimental or observational, longitudinal or cross-sectional, and prospective or retrospective. Additional features (e.g., controlled, randomized, or blinded) may be described that address bias. Two related challenging aspects of study design are defining an important research question and selecting an appropriate sample population. The sample population should represent the target population as much as possible. Furthermore, when comparing groups, it is important that the groups are as alike to each other as possible except for the variables of interest. Medical images are well suited for clinical research because imaging signs are categorical or numerical variables that might be predictors or outcomes of diseases or treatments. © 2013 Veterinary Radiology & Ultrasound.

NPP-VIIRS DNB-based reallocating subpopulations to mercury in Urumqi city cluster, central Asia

NASA Astrophysics Data System (ADS)

Zhou, X.; Feng, X. B.; Dai, W.; Li, P.; Ju, C. Y.; Bao, Z. D.; Han, Y. L.

2017-02-01

Accurate and update assignment of population-related environmental matters onto fine grid cells in oasis cities of arid areas remains challenging. We present the approach based on Suomi National Polar-orbiting Partnership (S-NPP) -Visible Infrared Imaging Radiometer Suite (VIIRS) Day/Night Band (DNB) to reallocate population onto a regular finer surface. The number of potential population to the mercury were reallocated onto 0.1x0.1 km reference grid in Urumqi city cluster of China’s Xinjiang, central Asia. The result of Monte Carlo modelling indicated that the range of 0.5 to 2.4 million people was reliable. The study highlights that the NPP-VIIRS DNB-based multi-layered, dasymetric, spatial method enhances our abilities to remotely estimate the distribution and size of target population at the street-level scale and has the potential to transform control strategies for epidemiology, public policy and other socioeconomic fields.

Ethical issues in using Twitter for population-level depression monitoring: a qualitative study.

PubMed

Mikal, Jude; Hurst, Samantha; Conway, Mike

2016-04-14

Recently, significant research effort has focused on using Twitter (and other social media) to investigate mental health at the population-level. While there has been influential work in developing ethical guidelines for Internet discussion forum-based research in public health, there is currently limited work focused on addressing ethical problems in Twitter-based public health research, and less still that considers these issues from users' own perspectives. In this work, we aim to investigate public attitudes towards utilizing public domain Twitter data for population-level mental health monitoring using a qualitative methodology. The study explores user perspectives in a series of five, 2-h focus group interviews. Following a semi-structured protocol, 26 Twitter users with and without a diagnosed history of depression discussed general Twitter use, along with privacy expectations, and ethical issues in using social media for health monitoring, with a particular focus on mental health monitoring. Transcripts were then transcribed, redacted, and coded using a constant comparative approach. While participants expressed a wide range of opinions, there was an overall trend towards a relatively positive view of using public domain Twitter data as a resource for population level mental health monitoring, provided that results are appropriately aggregated. Results are divided into five sections: (1) a profile of respondents' Twitter use patterns and use variability; (2) users' privacy expectations, including expectations regarding data reach and permanence; (3) attitudes towards social media based population-level health monitoring in general, and attitudes towards mental health monitoring in particular; (4) attitudes towards individual versus population-level health monitoring; and (5) users' own recommendations for the appropriate regulation of population-level mental health monitoring. Focus group data reveal a wide range of attitudes towards the use of public-domain social media "big data" in population health research, from enthusiasm, through acceptance, to opposition. Study results highlight new perspectives in the discussion of ethical use of public data, particularly with respect to consent, privacy, and oversight.

Needle decompression of tension pneumothorax: Population-based epidemiologic approach to adequate needle length in healthy volunteers in Northeast Germany.

PubMed

Hecker, Matthias; Hegenscheid, Katrin; Völzke, Henry; Hinz, Peter; Lange, Jörn; Ekkernkamp, Axel; Frank, Matthias

2016-01-01

Tension pneumothorax is one of the leading causes of preventable death in both military and civilian trauma patients. Needle decompression is recommended in trauma guidelines as an emergency procedure to relieve increased intrapleural pressure. The main reason for decompression failure is reported to be insufficient needle length in proportion to the chest wall thickness (CWT). So far, population-based epidemiologic data on CWT are missing. Therefore, it was the aim of this work to investigate the CWT in the second intercostal space, midclavicular line, based on magnetic resonance imaging data of a large population-based sample. The second aim of this study was to explore the potential risk of iatrogenic lesions caused by the proximity of the intended puncture track to the internal mammary artery. A total of 2,574 healthy volunteers (mean [SD] age, 53.3 [13.9] years; range, 21-89 years) from the population-based cohort Study of Health in Pomerania (SHIP) were enrolled. CWT and the distance from the intended puncture track to the internal mammary artery were investigated with the chest sequences of a standardized 1.5-T whole-body magnetic resonance imaging. For all 5,148 measured sites in 2,574 volunteers, the mean (SD) CWT was 5.1 (1.4) cm. The mean body mass index was determined to be 27.7 kg/m. The CWT correlated significantly with body weight and body mass index. The internal mammary artery was located medial to the intended puncture site in all participants; the mean (SD) distance was 5.7 (0.7) cm on the right and 5.5 (0.7) cm on the left side. Based on the population-based epidemiologic data presented in this study, the use of a needle of 7 cm in length is recommended to decompress a tension pneumothorax in the second intercostal space in the midclavicular line, which might successfully decompress more than 90% of the participants in this study. When using this anterior approach at the anatomically correct puncture site, safety margin to the internal mammary artery is sufficient so that the risk of iatrogenic lesion of the internal mammary artery should be minimal. Therapeutic/care management study, level IV.

Correction to: Associations between attention-deficit/hyperactivity disorder and autoimmune diseases are modified by sex: a population-based cross-sectional study.

PubMed

Hegvik, Tor-Arne; Instanes, Johanne Telnes; Haavik, Jan; Klungsøyr, Kari; Engeland, Anders

2018-05-01

The article "Associations between attention-deficit/hyperactivity disorder and autoimmune diseases are modified by sex: a population-based cross-sectional study", written by Tor-Arne Hegvik, Johanne Telnes Instanes, Jan Haavik, Kari Klungsøyr and Anders Engeland, was originally published electronically on the publisher's internet portal (currently SpringerLink) on October 5, 2017 without open access due to an error by the Springer editorial office in the processing of this article. The authors had originally opted for open access.

Comparative Epidemiology and Outcomes of Human Immunodeficiency virus (HIV), Non-HIV Non-transplant, and Solid Organ Transplant Associated Cryptococcosis: A Population-Based Study.

PubMed

George, Ige A; Spec, Andrej; Powderly, William G; Santos, Carlos A Q

2018-02-01

In this population-based study in the contemporary era in the United States, the proportion of human immunodeficiency virus (HIV)-negative patients with cryptococcosis approaches that in HIV-infected patients. Cryptococcosis is associated with higher mortality rates in HIV-negative patients (including organ transplant recipients). © The Author(s) 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Faith-Based Mental Health Interventions with African Americans: A Review

ERIC Educational Resources Information Center

Hays, Krystal; Aranda, Maria P.

2016-01-01

Faith-based interventions have emerged culturally sensitive way to address mental health issues among African Americans. This systematic review explores the scope and efficacy of faith-based mental health intervention outcomes among African Americans. Extracted data included the study population, setting, study design, intervention, adaptations,…

Selecting Populations for Non-Analogous Climate Conditions Using Universal Response Functions: The Case of Douglas-Fir in Central Europe.

PubMed

Chakraborty, Debojyoti; Wang, Tongli; Andre, Konrad; Konnert, Monika; Lexer, Manfred J; Matulla, Christoph; Schueler, Silvio

2015-01-01

Identifying populations within tree species potentially adapted to future climatic conditions is an important requirement for reforestation and assisted migration programmes. Such populations can be identified either by empirical response functions based on correlations of quantitative traits with climate variables or by climate envelope models that compare the climate of seed sources and potential growing areas. In the present study, we analyzed the intraspecific variation in climate growth response of Douglas-fir planted within the non-analogous climate conditions of Central and continental Europe. With data from 50 common garden trials, we developed Universal Response Functions (URF) for tree height and mean basal area and compared the growth performance of the selected best performing populations with that of populations identified through a climate envelope approach. Climate variables of the trial location were found to be stronger predictors of growth performance than climate variables of the population origin. Although the precipitation regime of the population sources varied strongly none of the precipitation related climate variables of population origin was found to be significant within the models. Overall, the URFs explained more than 88% of variation in growth performance. Populations identified by the URF models originate from western Cascades and coastal areas of Washington and Oregon and show significantly higher growth performance than populations identified by the climate envelope approach under both current and climate change scenarios. The URFs predict decreasing growth performance at low and middle elevations of the case study area, but increasing growth performance on high elevation sites. Our analysis suggests that population recommendations based on empirical approaches should be preferred and population selections by climate envelope models without considering climatic constrains of growth performance should be carefully appraised before transferring populations to planting locations with novel or dissimilar climate.

Postoperative radioactive iodine-131 ablation is not necessary among patients with intermediate-risk differentiated thyroid carcinoma: a population-based study.

PubMed

Zhang, Hong; Cai, Yuechang; Zheng, Li; Zhang, Zhanlei; Jiang, Ningyi

2017-01-01

To assess the effectiveness of radioactive iodine (RAI) ablation among patients with intermediate-risk differentiated thyroid cancer (DTC) following surgery. This population based study obtained information from the Surveillance, Epidemiology, and End Results (SEER) Program Research Data (1973-2013). National Cancer Institute, DCCPS, Surveillance Research Programme, Surveillance Systems Branch, released April 2016, based on the November 2015 submission. A total of 93,530 patients with primary thyroid cancer were identified in the SEER database during the period of 2004-2013 and focused on patients with DTC post-operatively treated or not treated with radioactive iodine (RAI). From these 9,127 patients were selected who had intermediate-risk DTC. A total of 8,601 patients were included in this study. For the overall population, the mean age of the population was 47.3 years and the majority were female (70.5%). Kaplan-Meier analysis found the mean overall survival time (os) for subjects with no radiation therapy which was 112.9 months and 114.9 months for those who received RAI ablation treatment (P<0.001). However, thyroid cancer-specific survival was not significantly different between treatment groups (117.7 vs. 118.0 months, log-rank test P=0.164). Overall survival and thyroid cancer-specific 1 year, 5 years, and 10-years survival rates were ≥89.8% and were similar between both treated groups. Multivariate analysis found age, gender, histologic type, and degree of lymph node metastases to be associated with OS, and age, gender, degree of lymph node metastasis and extra-thyroid tumor spread were independent factors for cancer-specific survival. In DTC patients with intermediate cancer risk multivariate analysis found that RAI was associated with a reduced risk of mortality compared with no radiation therapy (HR=0.710, 95% CI: 0.562-0.897, P=0.004) but no significant difference was seen in cancer-specific survival, either based on whole study population or on tumor size category. In DTC patients with intermediate cancer risk although postoperative RAI ablation following surgery showed a benefit in overall survival, no significant difference was seen in cancer-specific survival, either based on whole study population or on tumor size category.

Whole genome sequencing and imputation in isolated populations identify genetic associations with medically-relevant complex traits

PubMed Central

Southam, Lorraine; Gilly, Arthur; Süveges, Dániel; Farmaki, Aliki-Eleni; Schwartzentruber, Jeremy; Tachmazidou, Ioanna; Matchan, Angela; Rayner, Nigel W.; Tsafantakis, Emmanouil; Karaleftheri, Maria; Xue, Yali; Dedoussis, George; Zeggini, Eleftheria

2017-01-01

Next-generation association studies can be empowered by sequence-based imputation and by studying founder populations. Here we report ∼9.5 million variants from whole-genome sequencing (WGS) of a Cretan-isolated population, and show enrichment of rare and low-frequency variants with predicted functional consequences. We use a WGS-based imputation approach utilizing 10,422 reference haplotypes to perform genome-wide association analyses and observe 17 genome-wide significant, independent signals, including replicating evidence for association at eight novel low-frequency variant signals. Two novel cardiometabolic associations are at lead variants unique to the founder population sequences: chr16:70790626 (high-density lipoprotein levels beta −1.71 (SE 0.25), P=1.57 × 10−11, effect allele frequency (EAF) 0.006); and rs145556679 (triglycerides levels beta −1.13 (SE 0.17), P=2.53 × 10−11, EAF 0.013). Our findings add empirical support to the contribution of low-frequency variants in complex traits, demonstrate the advantage of including population-specific sequences in imputation panels and exemplify the power gains afforded by population isolates. PMID:28548082

Integrating mechanistic and polymorphism data to characterize human genetic susceptibility for environmental chemical risk assessment in the 21st century

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mortensen, Holly M., E-mail: mortensen.holly@epa.gov; Euling, Susan Y.

Response to environmental chemicals can vary widely among individuals and between population groups. In human health risk assessment, data on susceptibility can be utilized by deriving risk levels based on a study of a susceptible population and/or an uncertainty factor may be applied to account for the lack of information about susceptibility. Defining genetic susceptibility in response to environmental chemicals across human populations is an area of interest in the NAS' new paradigm of toxicity pathway-based risk assessment. Data from high-throughput/high content (HT/HC), including -omics (e.g., genomics, transcriptomics, proteomics, metabolomics) technologies, have been integral to the identification and characterization ofmore » drug target and disease loci, and have been successfully utilized to inform the mechanism of action for numerous environmental chemicals. Large-scale population genotyping studies may help to characterize levels of variability across human populations at identified target loci implicated in response to environmental chemicals. By combining mechanistic data for a given environmental chemical with next generation sequencing data that provides human population variation information, one can begin to characterize differential susceptibility due to genetic variability to environmental chemicals within and across genetically heterogeneous human populations. The integration of such data sources will be informative to human health risk assessment.« less

Effects of diabetes definition on global surveillance of diabetes prevalence and diagnosis: a pooled analysis of 96 population-based studies with 331 288 participants

PubMed Central

2015-01-01

Summary Background Diabetes has been defined on the basis of different biomarkers, including fasting plasma glucose (FPG), 2-h plasma glucose in an oral glucose tolerance test (2hOGTT), and HbA1c. We assessed the effect of different diagnostic definitions on both the population prevalence of diabetes and the classification of previously undiagnosed individuals as having diabetes versus not having diabetes in a pooled analysis of data from population-based health examination surveys in different regions. Methods We used data from 96 population-based health examination surveys that had measured at least two of the biomarkers used for defining diabetes. Diabetes was defined using HbA1c (HbA1c ≥6·5% or history of diabetes diagnosis or using insulin or oral hypoglycaemic drugs) compared with either FPG only or FPG-or-2hOGTT definitions (FPG ≥7·0 mmol/L or 2hOGTT ≥11·1 mmol/L or history of diabetes or using insulin or oral hypoglycaemic drugs). We calculated diabetes prevalence, taking into account complex survey design and survey sample weights. We compared the prevalences of diabetes using different definitions graphically and by regression analyses. We calculated sensitivity and specificity of diabetes diagnosis based on HbA1c compared with diagnosis based on glucose among previously undiagnosed individuals (ie, excluding those with history of diabetes or using insulin or oral hypoglycaemic drugs). We calculated sensitivity and specificity in each survey, and then pooled results using a random-effects model. We assessed the sources of heterogeneity of sensitivity by meta-regressions for study characteristics selected a priori. Findings Population prevalence of diabetes based on FPG-or-2hOGTT was correlated with prevalence based on FPG alone (r=0·98), but was higher by 2–6 percentage points at different prevalence levels. Prevalence based on HbA1c was lower than prevalence based on FPG in 42·8% of age–sex–survey groups and higher in another 41·6%; in the other 15·6%, the two definitions provided similar prevalence estimates. The variation across studies in the relation between glucose-based and HbA1c-based prevalences was partly related to participants' age, followed by natural logarithm of per person gross domestic product, the year of survey, mean BMI, and whether the survey population was national, subnational, or from specific communities. Diabetes defined as HbA1c 6·5% or more had a pooled sensitivity of 52·8% (95% CI 51·3–54·3%) and a pooled specificity of 99·74% (99·71–99·78%) compared with FPG 7·0 mmol/L or more for diagnosing previously undiagnosed participants; sensitivity compared with diabetes defined based on FPG-or-2hOGTT was 30·5% (28·7–32·3%). None of the preselected study-level characteristics explained the heterogeneity in the sensitivity of HbA1c versus FPG. Interpretation Different biomarkers and definitions for diabetes can provide different estimates of population prevalence of diabetes, and differentially identify people without previous diagnosis as having diabetes. Using an HbA1c-based definition alone in health surveys will not identify a substantial proportion of previously undiagnosed people who would be considered as having diabetes using a glucose-based test. Funding Wellcome Trust, US National Institutes of Health. PMID:26109024

Functional genomics annotation of a statistical epistasis network associated with bladder cancer susceptibility.

PubMed

Hu, Ting; Pan, Qinxin; Andrew, Angeline S; Langer, Jillian M; Cole, Michael D; Tomlinson, Craig R; Karagas, Margaret R; Moore, Jason H

2014-04-11

Several different genetic and environmental factors have been identified as independent risk factors for bladder cancer in population-based studies. Recent studies have turned to understanding the role of gene-gene and gene-environment interactions in determining risk. We previously developed the bioinformatics framework of statistical epistasis networks (SEN) to characterize the global structure of interacting genetic factors associated with a particular disease or clinical outcome. By applying SEN to a population-based study of bladder cancer among Caucasians in New Hampshire, we were able to identify a set of connected genetic factors with strong and significant interaction effects on bladder cancer susceptibility. To support our statistical findings using networks, in the present study, we performed pathway enrichment analyses on the set of genes identified using SEN, and found that they are associated with the carcinogen benzo[a]pyrene, a component of tobacco smoke. We further carried out an mRNA expression microarray experiment to validate statistical genetic interactions, and to determine if the set of genes identified in the SEN were differentially expressed in a normal bladder cell line and a bladder cancer cell line in the presence or absence of benzo[a]pyrene. Significant nonrandom sets of genes from the SEN were found to be differentially expressed in response to benzo[a]pyrene in both the normal bladder cells and the bladder cancer cells. In addition, the patterns of gene expression were significantly different between these two cell types. The enrichment analyses and the gene expression microarray results support the idea that SEN analysis of bladder in population-based studies is able to identify biologically meaningful statistical patterns. These results bring us a step closer to a systems genetic approach to understanding cancer susceptibility that integrates population and laboratory-based studies.

Estimating HIV Prevalence in Zimbabwe Using Population-Based Survey Data

PubMed Central

Chinomona, Amos; Mwambi, Henry Godwell

2015-01-01

Estimates of HIV prevalence computed using data obtained from sampling a subgroup of the national population may lack the representativeness of all the relevant domains of the population. These estimates are often computed on the assumption that HIV prevalence is uniform across all domains of the population. Use of appropriate statistical methods together with population-based survey data can enhance better estimation of national and subgroup level HIV prevalence and can provide improved explanations of the variation in HIV prevalence across different domains of the population. In this study we computed design-consistent estimates of HIV prevalence, and their respective 95% confidence intervals at both the national and subgroup levels. In addition, we provided a multivariable survey logistic regression model from a generalized linear modelling perspective for explaining the variation in HIV prevalence using demographic, socio-economic, socio-cultural and behavioural factors. Essentially, this study borrows from the proximate determinants conceptual framework which provides guiding principles upon which socio-economic and socio-cultural variables affect HIV prevalence through biological behavioural factors. We utilize the 2010–11 Zimbabwe Demographic and Health Survey (2010–11 ZDHS) data (which are population based) to estimate HIV prevalence in different categories of the population and for constructing the logistic regression model. It was established that HIV prevalence varies greatly with age, gender, marital status, place of residence, literacy level, belief on whether condom use can reduce the risk of contracting HIV and level of recent sexual activity whereas there was no marked variation in HIV prevalence with social status (measured using a wealth index), method of contraceptive and an individual’s level of education. PMID:26624280

Use of driving-impairing medicines by a Spanish population: a population-based registry study

PubMed Central

Gutierrez-Abejón, Eduardo; Herrera-Gómez, Francisco; Criado-Espegel, Paloma

2017-01-01

Objective To assess the use of driving-impairing medicines (DIM) in the general population with special reference to length of use and concomitant use. Design Population-based registry study. Setting The year 2015 granted medicines consumption data recorded in the Castile and León (Spain) medicine dispensation registry was consulted. Participants Medicines and DIM consumers from a Spanish population (Castile and León: 2.4 million inhabitants). Exposure Medicines and DIM consumption. Patterns of use by age and gender based on the length of use (acute: 1–7 days, subacute: 8–29 days and chronic use: ≥30 days) were of interest. Estimations regarding the distribution of licensed drivers by age and gender were employed to determine the patterns of use of DIM. Results DIM were consumed by 34.4% (95% CI 34.3% to 34.5%) of the general population in 2015, more commonly with regularity (chronic use: 22.5% vs acute use: 5.3%) and more frequently by the elderly. On average, 2.3 DIM per person were dispensed, particularly to chronic users (2.8 DIM per person). Age and gender distribution differences were observed between the Castile and León medicine dispensation registry data and the drivers’ license census data. Of all DIM dispensed, 83.8% were in the Anatomical Therapeutic Chemical code group nervous system medicines (N), which were prescribed to 29.2% of the population. Conclusions The use of DIM was frequent in the general population. Chronic use was common, but acute and subacute use should also be considered. This finding highlights the need to make patients, health professionals, health providers, medicine regulatory agencies and policy-makers at large aware of the role DIM play in traffic safety. PMID:29170289

A Population-Based Approach to Study the Impact of PROP Perception on Food Liking in Populations along the Silk Road

PubMed Central

Robino, Antonietta; Mezzavilla, Massimo; Pirastu, Nicola; Dognini, Maddalena; Tepper, Beverly J.; Gasparini, Paolo

2014-01-01

Taste is one of the main factors determining food choices. Differences in PROP bitter taste perception have been implicated in individual differences in food preferences and selection. The present study examined associations between, PROP phenotypes, self-reported food liking and TAS2R38 polymorphisms, the major gene implicated in PROP bitterness, in six different populations of the Caucasus and Central Asia, located along the ancient Silk Road. Differences in the distribution of PROP phenotypes across populations were detected, with a higher frequency of super tasters in Tajikistan (31.3%) and Armenia (39.0%) and a higher frequency of non tasters in Georgia (50.9%). While no relationships were observed between PROP phenotypes and food liking using standard statistical tests, we used an approach based on comparison of distance matrices derived from these data. The first matrix compared the food liking ratings of each population to all others pairwise using the Kruskal-Wallis test (at p<0.00063), and the second one compared the distribution of PROP phenotypes across all populations in a similar manner calculating the chi-square statistic as a distance measure. A strong correlation between the two matrices was found (Mantel test: r = 0.67, p-value = 0.03), suggesting that the pattern of food liking across populations was closely related to the distribution of PROP phenotypes. This same relationship was not observed when TAS2R38 genotypes were substituted for PROP phenotypes in this analysis. Our data suggest that a population-based approach utilizing distance matrices is a useful technique for detecting PROP-related differences in food liking and can be applied to other taste phenotypes. PMID:24626196

A population-based approach to study the impact of PROP perception on food liking in populations along the Silk Road.

PubMed

Robino, Antonietta; Mezzavilla, Massimo; Pirastu, Nicola; Dognini, Maddalena; Tepper, Beverly J; Gasparini, Paolo

2014-01-01

Taste is one of the main factors determining food choices. Differences in PROP bitter taste perception have been implicated in individual differences in food preferences and selection. The present study examined associations between, PROP phenotypes, self-reported food liking and TAS2R38 polymorphisms, the major gene implicated in PROP bitterness, in six different populations of the Caucasus and Central Asia, located along the ancient Silk Road. Differences in the distribution of PROP phenotypes across populations were detected, with a higher frequency of super tasters in Tajikistan (31.3%) and Armenia (39.0%) and a higher frequency of non tasters in Georgia (50.9%). While no relationships were observed between PROP phenotypes and food liking using standard statistical tests, we used an approach based on comparison of distance matrices derived from these data. The first matrix compared the food liking ratings of each population to all others pairwise using the Kruskal-Wallis test (at p<0.00063), and the second one compared the distribution of PROP phenotypes across all populations in a similar manner calculating the chi-square statistic as a distance measure. A strong correlation between the two matrices was found (Mantel test: r = 0.67, p-value = 0.03), suggesting that the pattern of food liking across populations was closely related to the distribution of PROP phenotypes. This same relationship was not observed when TAS2R38 genotypes were substituted for PROP phenotypes in this analysis. Our data suggest that a population-based approach utilizing distance matrices is a useful technique for detecting PROP-related differences in food liking and can be applied to other taste phenotypes.

Prevalence and conversion to dementia of Mild Cognitive Impairment in an elderly Italian population.

PubMed

Limongi, Federica; Siviero, Paola; Noale, Marianna; Gesmundo, Antonella; Crepaldi, Gaetano; Maggi, Stefania

2017-06-01

Mild Cognitive Impairment (MCI) represents a significant risk factor for dementia but there are only a few Italian population studies on its prevalence and its rate of conversion to dementia. Aim of this study was to assess the prevalence of MCI, its subtypes, and rates of conversion to dementia 1 year later in an elderly Italian population. The data are based on an Italian multicenter population-based cohort study with both cross-sectional and longitudinal components. Two thousand three hundred thirty-seven individuals over 65 underwent screening, clinical confirmation and 1-year follow-up. The prevalence of MCI was 21.6% and the amnestic multiple domain was the most frequent subtype (63.2%). The conversion rate to dementia was 4.1% and was found only in the amnestic multiple domain and in the unclassifiable subjects, persons with cognitive deficit but neither demented nor with MCI. The prevalence of MCI in this population sample was similar to that found in other population studies using Petersen's modified MCI criteria as well as his original criteria. With regard to conversion to dementia, our results emphasize the importance to better classify the unclassifiable subjects at high risk of progression to dementia and also at risk of being undiagnosed and untreated. MCI is characterized by extreme variability and instability. Data on the prevalence and the rate of conversion from MCI to dementia are difficult to compare given the important differences from study to study especially with regard to the diagnostic criteria utilized and their operationalization.

History of research on modelling gypsy moth population ecology

Treesearch

J. J. Colbert

1991-01-01

History of research to develop models of gypsy moth population dynamics and some related studies are described. Empirical regression-based models are reviewed, and then the more comprehensive process models are discussed. Current model- related research efforts are introduced.

75 FR 34462 - Center for Scientific Review; Notice of Closed Meetings

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-17

...: Technology-Based Adherence Interventions for Substance Abusing Populations with HIV (R34). Date: July 9, 2010...: Social Science and Population Studies. Date: July 14, 2010. Time: 1 p.m. to 3:30 p.m. Agenda: To review...

Measuring Sexual Behavior Stigma to Inform Effective HIV Prevention and Treatment Programs for Key Populations

PubMed Central

Hargreaves, James R; Sprague, Laurel; Stangl, Anne L; Baral, Stefan D

2017-01-01

Background The levels of coverage of human immunodeficiency virus (HIV) treatment and prevention services needed to change the trajectory of the HIV epidemic among key populations, including gay men and other men who have sex with men (MSM) and sex workers, have consistently been shown to be limited by stigma. Objective The aim of this study was to propose an agenda for the goals and approaches of a sexual behavior stigma surveillance effort for key populations, with a focus on collecting surveillance data from 4 groups: (1) members of key population groups themselves (regardless of HIV status), (2) people living with HIV (PLHIV) who are also members of key populations, (3) members of nonkey populations, and (4) health workers. Methods We discuss strengths and weaknesses of measuring multiple different types of stigma including perceived, anticipated, experienced, perpetrated, internalized, and intersecting stigma as measured among key populations themselves, as well as attitudes or beliefs about key populations as measured among other groups. Results With the increasing recognition of the importance of stigma, consistent and validated stigma metrics for key populations are needed to monitor trends and guide immediate action. Evidence-based stigma interventions may ultimately be the key to overcoming the barriers to coverage and retention in life-saving antiretroviral-based HIV prevention and treatment programs for key populations. Conclusions Moving forward necessitates the integration of validated stigma scales in routine HIV surveillance efforts, as well as HIV epidemiologic and intervention studies focused on key populations, as a means of tracking progress toward a more efficient and impactful HIV response. PMID:28446420

Assessing the Validity of a Stage Measure on Physical Activity in a Population-Based Sample of Individuals with Type 1 or Type 2 Diabetes

ERIC Educational Resources Information Center

Plotnikoff, Ronald C.; Lippke, Sonia; Reinbold-Matthews, Melissa; Courneya, Kerry S.; Karunamuni, Nandini; Sigal, Ronald J.; Birkett, Nicholas

2007-01-01

This study was designed to test the validity of a transtheoretical model's physical activity (PA) stage measure with intention and different intensities of behavior in a large population-based sample of adults living with diabetes (Type 1 diabetes, n = 697; Type 2 diabetes, n = 1,614) and examine different age groups. The overall…

Measuring self-management of patients' and employees' health: further validation of the Patient Activation Measure (PAM) based on its relation to employee characteristics.

PubMed

Fowles, Jinnet Briggs; Terry, Paul; Xi, Min; Hibbard, Judith; Bloom, Christine Taddy; Harvey, Lisa

2009-10-01

Evaluate the Patient Activation Measure (PAM) in relation to personal characteristics in employed populations. Further validate the PAM for use in improving clinical or employer-based health-intervention programs. Data for analysis were taken from baseline survey information and health screenings collected during a randomized, controlled trial testing two different health promotion programs. Study population included 625 employees (predominantly white collar) from two companies in the northern Midwest of the United States: a large, integrated health care system and a national airline. PAM's psychometric properties are robust in two employed populations. Activation is directly related not only to health status, but also to job performance measures. The strong positive relationship of PAM to measures of healthy behavior, health information-seeking and readiness-to-change further validate the measure. Commonly, a difference of 5 points on the PAM separated healthy from less healthy behaviors. Activation can be understood in a broader population health context and need not be restricted to people with chronic illnesses. The study provides guidance on how to interpret PAM scores. The PAM can be used as part of any health-intervention program designed to improve patients' or employees' self-management skills, whether the program is clinic-based or employer-based. 2009 Elsevier Ireland Ltd.

Unsupervised discovery of microbial population structure within metagenomes using nucleotide base composition

PubMed Central

Saeed, Isaam; Tang, Sen-Lin; Halgamuge, Saman K.

2012-01-01

An approach to infer the unknown microbial population structure within a metagenome is to cluster nucleotide sequences based on common patterns in base composition, otherwise referred to as binning. When functional roles are assigned to the identified populations, a deeper understanding of microbial communities can be attained, more so than gene-centric approaches that explore overall functionality. In this study, we propose an unsupervised, model-based binning method with two clustering tiers, which uses a novel transformation of the oligonucleotide frequency-derived error gradient and GC content to generate coarse groups at the first tier of clustering; and tetranucleotide frequency to refine these groups at the secondary clustering tier. The proposed method has a demonstrated improvement over PhyloPythia, S-GSOM, TACOA and TaxSOM on all three benchmarks that were used for evaluation in this study. The proposed method is then applied to a pyrosequenced metagenomic library of mud volcano sediment sampled in southwestern Taiwan, with the inferred population structure validated against complementary sequencing of 16S ribosomal RNA marker genes. Finally, the proposed method was further validated against four publicly available metagenomes, including a highly complex Antarctic whale-fall bone sample, which was previously assumed to be too complex for binning prior to functional analysis. PMID:22180538

The rationale/design of the Guimarães/Vizela study: a multimodal population-based cohort study to determine global cardiovascular risk and disease.

PubMed

Cunha, Pedro Guimarães; Cotter, Jorge; Oliveira, Pedro; Vila, Isabel; Sousa, Nuno

2014-06-01

Cardiovascular disease and dementia are growing medical and social problems in aging societies. Appropriate knowledge of cardiovascular disease and cognitive decline risk factors (RFs) are critical for global CVR health preventive intervention. Many epidemiological studies use case definition based on data collected/measured in a single visit, a fact that can overestimate prevalence rates and distant from clinical practice demanding criteria. Portugal displays an elevated stroke mortality rate. However, population's global CV risk characterization is limited, namely, considering traditional/nontraditional RF and new intermediate phenotypes of CV and renal disease. Association of hemodynamic variables (pulse wave velocity and central blood pressure) with global CVR stratification, cognitive performance, and kidney disease are practically inexistent at a dwelling population level. After reviewing published data, we designed a population-based cohort study to analyze the prevalence of these cardiovascular RFs and intermediate phenotypes, using random sampling of adult dwellers living in 2 adjacent cities. Strict definition of phenotypes was planned: subjects were observed twice, and several hemodynamic and other biological variables measured at least 3 months apart. Three thousand thirty-eight subjects were enrolled, and extensive data collection (including central and peripheral blood pressure, pulse wave velocity), sample processing, and biobank edification were carried out. One thousand forty-seven cognitive evaluations were performed. Seeking for CV risk reclassification, early identification of subjects at risk, and evidence of early vascular aging and cognitive and renal function decline, using the strict daily clinical practice criteria, will lead to better resource allocation in preventive measures at a population level.

How gambling harms experienced by Pacific people in New Zealand amplify when they are culture-related.

PubMed

Kolandai-Matchett, Komathi; Langham, Erika; Bellringer, Maria; Siitia, Pesio Ah-Honi

2017-01-01

Pacific people in New Zealand are a minority ethnic population identified in national prevalence studies as having the highest risk of developing gambling problems. As earlier studies identified some links between culture and gambling for this population, our study aimed to deepen understanding of these links and their role in explaining the disproportionate gambling harms experienced by Pacific people. To achieve this aim we employed intersectionality as a theoretical framework to explore the culture-gambling intersection for this population group. We analysed data from a subset of focus groups conducted for a broad study of gambling harms in New Zealand. The subset was selected based on the presence of individuals knowledgeable about Pacific people's gambling behaviours, including staff from Pacific problem gambling treatment services who provided examples from a cultural perspective. We identified themes at a latent level via an interpretive process to identify underlying cultural contexts of gambling harms. Findings indicated that whilst harms experienced by Pacific people were similar to those identified amongst the general population, the cultural contexts in which some harms manifested were complex. This paper contributes to the existing knowledge base about gambling harms for Pacific people in relation to six culture-gambling intersecting themes that emerged from the data: collectivism, gift-giving, gambling-based fundraising, patriarchy, beliefs about blessings, and sports celebrities. Findings are discussed in relation to the current knowledge of gambling and conceptualisations of gambling harm within Pacific communities. Implications for culturally appropriate harm minimisation strategies and prevention interventions for this population are suggested.

Anti-Smoking Socialization Beliefs among Rural Native American and White Parents of Young Children

ERIC Educational Resources Information Center

Kegler, Michelle C.; Malcoe, Lorraine Halinka

2005-01-01

This study assesses similarities and differences in anti-smoking socialization beliefs of White and Native American parents in a low-income, rural population in northeastern Oklahoma. Data are from a population-based, cross-sectional children's environmental health study in which in-home interviews were conducted with 356 parents (56.2% White,…

Cause-Specific Mortality and Death Certificate Reporting in Adults with Moderate to Profound Intellectual Disability

ERIC Educational Resources Information Center

Tyrer, F.; McGrother, C.

2009-01-01

Background: The study of premature deaths in people with intellectual disability (ID) has become the focus of recent policy initiatives in England. This is the first UK population-based study to explore cause-specific mortality in adults with ID compared with the general population. Methods: Cause-specific standardised mortality ratios (SMRs) and…

A Population-Based Study of Job Stress in Mexican Americans, Non-Hispanic Blacks, and Non-Hispanic Whites

ERIC Educational Resources Information Center

Perez, Norma; Franzini, Luisa; Freeman, Daniel H.; Ju, Hyunsu; Peek, Kristen

2011-01-01

There is little known about the association between socioeconomic status and job stress in Mexican Americans. To address this issue, data were originated on a community level using personal interviews from working Mexican Americans using a multistage probability sample. In this study we described the population's sociodemographic characteristics,…

A Study of Legal Manpower Demand and Supply in Pennsylvania.

ERIC Educational Resources Information Center

Durkee, Frank M.

This study was directed toward an examination of the legal manpower system and its response to needs in Pennsylvania. Information based on surveys is presented on: (1) lawyer-population ratios by counties, lawyer-area ratios by counties, and lawyer ratios to population and area in the State; (2) legal manpower demand in terms of correlations…

Suicide after release from prison - a population-based cohort study from Sweden

PubMed Central

Haglund, Axel; Tidemalm, Dag; Jokinen, Jussi; Långström, Niklas; Liechtenstein, Paul; Fazel, Seena; Runeson, Bo

2015-01-01

Objective Released prisoners have high suicide rates compared with the general population, but little is known about risk factors and possible causal pathways. We conducted a population-based cohort study to investigate rates and risk factors for suicide in people previously imprisoned. Methods We identified individuals released from prison in Sweden between January 1, 2005 and December 31, 2009 through linkage of national population-based registers. Released prisoners were followed from the day of release until death, emigration, new incarceration, or December 31, 2009. Survival analyses were conducted to compare incidence rates and psychiatric morbidity with non-convicted population controls matched on gender and year of birth. Results We identified 38,995 releases among 26,953 prisoners (7.6% females) during 2005-2009. Overall, 127 suicides occurred, accounting for 14% of all deaths after release (n=920). The mean suicide rate was 204 per 100,000 person years yielding an incidence rate ratio of 18.2 (95% CI 13.9-23.8) compared with general population controls. Previous substance use disorder (Hazard Ratio [HR]=2.1, 1.4-3.2), suicide attempt (HR=2.5, 1.7-3.7), and being born in Sweden vs. abroad (HR=2.1, 1.2-3.6) were independent risk factors for suicide after release. Conclusions Released prisoners are at high suicide risk and with a slightly different pattern of psychiatric risk factors for suicide compared with the general population. Results suggest appropriate allocation of resources to facilitate transition to life outside prison and increased attention to prisoners with both a previous suicide attempt and substance use disorder. PMID:25373114

Individualized head-related transfer functions based on population grouping.

PubMed

Xu, Song; Li, Zhizhong; Salvendy, Gavriel

2008-11-01

A method is proposed to divide a population into different groups for partial individualization of head-related transfer functions (HRTFs). Borrowing the basic idea in sizing system design, factor analysis is used to identify the most representative measurements which are then in a case study used to group the population. The comparison between the group mean HRTFs and the population mean HRTFs shows that the group mean HRTFs could greatly reduce spectral distortion at most sampled positions.

A Bayesian approach to the creation of a study-customized neonatal brain atlas

PubMed Central

Zhang, Yajing; Chang, Linda; Ceritoglu, Can; Skranes, Jon; Ernst, Thomas; Mori, Susumu; Miller, Michael I.; Oishi, Kenichi

2014-01-01

Atlas-based image analysis (ABA), in which an anatomical “parcellation map” is used for parcel-by-parcel image quantification, is widely used to analyze anatomical and functional changes related to brain development, aging, and various diseases. The parcellation maps are often created based on common MRI templates, which allow users to transform the template to target images, or vice versa, to perform parcel-by-parcel statistics, and report the scientific findings based on common anatomical parcels. The use of a study-specific template, which represents the anatomical features of the study population better than common templates, is preferable for accurate anatomical labeling; however, the creation of a parcellation map for a study-specific template is extremely labor intensive, and the definitions of anatomical boundaries are not necessarily compatible with those of the common template. In this study, we employed a Volume-based Template Estimation (VTE) method to create a neonatal brain template customized to a study population, while keeping the anatomical parcellation identical to that of a common MRI atlas. The VTE was used to morph the standardized parcellation map of the JHU-neonate-SS atlas to capture the anatomical features of a study population. The resultant “study-customized” T1-weighted and diffusion tensor imaging (DTI) template, with three-dimensional anatomical parcellation that defined 122 brain regions, was compared with the JHU-neonate-SS atlas, in terms of the registration accuracy. A pronounced increase in the accuracy of cortical parcellation and superior tensor alignment were observed when the customized template was used. With the customized atlas-based analysis, the fractional anisotropy (FA) detected closely approximated the manual measurements. This tool provides a solution for achieving normalization-based measurements with increased accuracy, while reporting scientific findings in a consistent framework. PMID:25026155

Population Structure, Genetic Diversity and Molecular Marker-Trait Association Analysis for High Temperature Stress Tolerance in Rice

PubMed Central

Barik, Saumya Ranjan; Sahoo, Ambika; Mohapatra, Sudipti; Nayak, Deepak Kumar; Mahender, Anumalla; Meher, Jitandriya; Anandan, Annamalai

2016-01-01

Rice exhibits enormous genetic diversity, population structure and molecular marker-traits associated with abiotic stress tolerance to high temperature stress. A set of breeding lines and landraces representing 240 germplasm lines were studied. Based on spikelet fertility percent under high temperature, tolerant genotypes were broadly classified into four classes. Genetic diversity indicated a moderate level of genetic base of the population for the trait studied. Wright’s F statistic estimates showed a deviation of Hardy-Weinberg expectation in the population. The analysis of molecular variance revealed 25 percent variation between population, 61 percent among individuals and 14 percent within individuals in the set. The STRUCTURE analysis categorized the entire population into three sub-populations and suggested that most of the landraces in each sub-population had a common primary ancestor with few admix individuals. The composition of materials in the panel showed the presence of many QTLs representing the entire genome for the expression of tolerance. The strongly associated marker RM547 tagged with spikelet fertility under stress and the markers like RM228, RM205, RM247, RM242, INDEL3 and RM314 indirectly controlling the high temperature stress tolerance were detected through both mixed linear model and general linear model TASSEL analysis. These markers can be deployed as a resource for marker-assisted breeding program of high temperature stress tolerance. PMID:27494320

Population Structure, Genetic Diversity and Molecular Marker-Trait Association Analysis for High Temperature Stress Tolerance in Rice.

PubMed

Pradhan, Sharat Kumar; Barik, Saumya Ranjan; Sahoo, Ambika; Mohapatra, Sudipti; Nayak, Deepak Kumar; Mahender, Anumalla; Meher, Jitandriya; Anandan, Annamalai; Pandit, Elssa

2016-01-01

Rice exhibits enormous genetic diversity, population structure and molecular marker-traits associated with abiotic stress tolerance to high temperature stress. A set of breeding lines and landraces representing 240 germplasm lines were studied. Based on spikelet fertility percent under high temperature, tolerant genotypes were broadly classified into four classes. Genetic diversity indicated a moderate level of genetic base of the population for the trait studied. Wright's F statistic estimates showed a deviation of Hardy-Weinberg expectation in the population. The analysis of molecular variance revealed 25 percent variation between population, 61 percent among individuals and 14 percent within individuals in the set. The STRUCTURE analysis categorized the entire population into three sub-populations and suggested that most of the landraces in each sub-population had a common primary ancestor with few admix individuals. The composition of materials in the panel showed the presence of many QTLs representing the entire genome for the expression of tolerance. The strongly associated marker RM547 tagged with spikelet fertility under stress and the markers like RM228, RM205, RM247, RM242, INDEL3 and RM314 indirectly controlling the high temperature stress tolerance were detected through both mixed linear model and general linear model TASSEL analysis. These markers can be deployed as a resource for marker-assisted breeding program of high temperature stress tolerance.

Prevalence and causes of low vision and blindness in an urban population: The Chennai Glaucoma Study.

PubMed

Vijaya, Lingam; George, Ronnie; Asokan, Rashima; Velumuri, Lokapavani; Ramesh, Sathyamangalam Ve

2014-04-01

To evaluate the prevalence and causes of low vision and blindness in an urban south Indian population. Population-based cross-sectional study. Exactly 3850 subjects aged 40 years and above from Chennai city were examined at a dedicated facility in the base hospital. All subjects had a complete ophthalmic examination that included best-corrected visual acuity. Low vision and blindness were defined using World Health Organization (WHO) criteria. The influence of age, gender, literacy, and occupation was assessed using multiple logistic regression. Chi-square test, t-test, and multivariate analysis were used. Of the 4800 enumerated subjects, 3850 subjects (1710 males, 2140 females) were examined (response rate, 80.2%). The prevalence of blindness was 0.85% (95% CI 0.6-1.1%) and was positively associated with age and illiteracy. Cataract was the leading cause (57.6%) and glaucoma was the second cause (16.7%) for blindness. The prevalence of low vision was 2.9% (95% CI 2.4-3.4%) and visual impairment (blindness + low vision) was 3.8% (95% CI 3.2-4.4%). The primary causes for low vision were refractive errors (68%) and cataract (22%). In this urban population based study, cataract was the leading cause for blindness and refractive error was the main reason for low vision.

Interprofessional Graduate Students' Perspectives on Caring for Vulnerable Populations.

PubMed

Wright, Patricia Moyle; Hanson, Mary Jane S

The purpose of this focus group study was to explore graduate students' clinical experiences with vulnerable populations, perceived barriers to care, and ethical issues related to caring for disenfranchised groups. Furthermore, based on their experiences, the students were asked to share suggestions for curricular changes that could enhance care for vulnerable populations through interdisciplinary collaboration and multidisciplinary projects. The responses of the participants add to what is known about the care of vulnerable populations, offering a first-hand description of students' preparation for work with vulnerable populations and the interdisciplinary team.

Thyroid dysfunction in an adult female population: A population-based study of Latin American Vertebral Osteoporosis Study (LAVOS) - Puerto Rico site.

PubMed

González-Rodríguez, Loida A; Felici-Giovanini, Marcos E; Haddock, Lillian

2013-06-01

To determine the prevalence of hypothyroidism in an adult female population in Puerto Rico and to determine the relationship between hypothyroidism, bone mineral density and vertebral and non-vertebral fractures in this population. Data from the 400 subjects' database of the Latin American Vertebral Osteoporosis Study (LAVOS), Puerto Rico site was reviewed. Patient's medical history, anthropometric data, current medications, laboratories, and DXA results was extracted. Subjects with thyroid dysfunction were identified based on their previous medical history and levels of TSH. Bone Mineral Density was classified using the World Health Organization criteria. Crude prevalence of thyroid dysfunction were estimated with a confidence of 95% and weighted by the population distribution by age, according to the distribution by age group in the 2000 census. Bone mineral densities and prevalence of vertebral and non-vertebral fractures were compared among the groups. The weighted prevalence of hyperthyroidism in this population was 0.0043% (95% CI: -0.0021%, 0.0107%). The weighted prevalence of hypothyroidism was 24.2% (95% CI: 19.9%, 28.4%). Increased prevalence of hypothyroidism was found in participants 70 years or older. The mean BMD at spine, hip and femoral neck was similar among the groups. No difference in the proportion of participants with vertebral and non-vertebral fractures was found among the groups. Our study found a high prevalence of hypothyroidism among adult postmenopausal females in Puerto Rico. No association between hypothyroidism and decreased bone mineral densities, vertebral or non-vertebral fractures was found in this population.

Hospice care in a commercial preferred provider organization population in Tennessee.

PubMed

Coulter, Steven L; Melvin, Terry; Carden, J Payne; Mathis, Rick S

2015-03-01

This study was undertaken to examine two aspects of care at the end of life. First, we wanted to see whether the cost savings demonstrated repeatedly in the US Medicare hospice population would also be observed in a commercial population in Tennessee. They were. The second primary interest we had was whether there were certain medical services that seemed to presage death. We found four categories of services that profoundly increase in number as the end of life is approached: primary care, hospital-based specialist, non-hospital based specialist, and oncologist services. It is hoped that these findings could lead to a simple predictive model based on readily available claims data to help identify candidates for Hospice Care earlier. © The Author(s) 2013.

Increased prevalence of metabolic syndrome in non-obese asian Indian-an urban-rural comparison.

PubMed

Mahadik, S R; Deo, S S; Mehtalia, S D

2007-06-01

In the present study we evaluated the association of insulin resistance (IR) with different components of Metabolic Syndrome (MS) in an Asian Indian population, and performed a comparative study between urban and rural populations of India. A Total of 267 urban men and women aged 25-70 years participated in this study. RESULTS were compared with rural data from a previously published study. Fasting serum insulin, uric acid, and lipid profile were measured along with fasting and 2 hour plasma glucose. Association of MS and IR was studied by using univariate regression analysis. Prevalence of MS was significantly higher in the urban population compared to that of the rural population (35.2% vs 20.6%, chi(2) = 23.2, p < 0.001). Calculated insulin resistence (HOMA-IR) was common in MS group of both populations. Percentage prevalence of IR was high and almost the same in both population (42%). Percentage prevalence of abdominal obesity and hypertriglyceridemia was significantly higher in the urban population compared to the rural population. Linear regression analysis of IR significantly correlated with different components of MS of both the population. The significant finding of the present study was that the rural population exhibited a high prevalence of MS and IR, though nonobese. IR correlated with components of MS not only in the urban but also in the rural population. To reduce the incidence of Type 2 Diabetes (T2DM) and cardiovascular disease (CVD) in our populations, early identification of populations at risk based on prevalence of MS and IR will become of prime importance.

Evaluating and improving count-based population inference: A case study from 31 years of monitoring Sandhill Cranes

USGS Publications Warehouse

Gerber, Brian D.; Kendall, William L.

2017-01-01

Monitoring animal populations can be difficult. Limited resources often force monitoring programs to rely on unadjusted or smoothed counts as an index of abundance. Smoothing counts is commonly done using a moving-average estimator to dampen sampling variation. These indices are commonly used to inform management decisions, although their reliability is often unknown. We outline a process to evaluate the biological plausibility of annual changes in population counts and indices from a typical monitoring scenario and compare results with a hierarchical Bayesian time series (HBTS) model. We evaluated spring and fall counts, fall indices, and model-based predictions for the Rocky Mountain population (RMP) of Sandhill Cranes (Antigone canadensis) by integrating juvenile recruitment, harvest, and survival into a stochastic stage-based population model. We used simulation to evaluate population indices from the HBTS model and the commonly used 3-yr moving average estimator. We found counts of the RMP to exhibit biologically unrealistic annual change, while the fall population index was largely biologically realistic. HBTS model predictions suggested that the RMP changed little over 31 yr of monitoring, but the pattern depended on assumptions about the observational process. The HBTS model fall population predictions were biologically plausible if observed crane harvest mortality was compensatory up to natural mortality, as empirical evidence suggests. Simulations indicated that the predicted mean of the HBTS model was generally a more reliable estimate of the true population than population indices derived using a moving 3-yr average estimator. Practitioners could gain considerable advantages from modeling population counts using a hierarchical Bayesian autoregressive approach. Advantages would include: (1) obtaining measures of uncertainty; (2) incorporating direct knowledge of the observational and population processes; (3) accommodating missing years of data; and (4) forecasting population size.

The 10-year Absolute Risk of Cardiovascular (CV) Events in Northern Iran: a Population Based Study

PubMed Central

Motamed, Nima; Mardanshahi, Alireza; Saravi, Benyamin Mohseni; Siamian, Hasan; Maadi, Mansooreh; Zamani, Farhad

2015-01-01

Background: The present study was conducted to estimate 10-year cardiovascular disease events (CVD) risk using three instruments in northern Iran. Material and methods: Baseline data of 3201 participants 40-79 of a population based cohort which was conducted in Northern Iran were analyzed. Framingham risk score (FRS), World Health Organization (WHO) risk prediction charts and American college of cardiovascular / American heart association (ACC/AHA) tool were applied to assess 10-year CVD events risk. The agreement values between the risk assessment instruments were determined using the kappa statistics. Results: Our study estimated 53.5%of male population aged 40-79 had a 10 –year risk of CVD events≥10% based on ACC/AHA approach, 48.9% based on FRS and 11.8% based on WHO risk charts. A 10 –year risk≥10% was estimated among 20.1% of women using the ACC/AHA approach, 11.9%using FRS and 5.7%using WHO tool. ACC/AHA and Framingham tools had closest agreement in the estimation of 10-year risk≥10% (κ=0.7757) in meanwhile ACC/AHA and WHO approaches displayed highest agreement (κ=0.6123) in women. Conclusion: Different estimations of 10-year risk of CVD event were provided by ACC/AHA, FRS and WHO approaches. PMID:26236160

Impact of Concomitant Chemotherapy on Outcomes of Radiation Therapy for Head-and-Neck Cancer: A Population-Based Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gupta, Shlok; Kong, Weidong; Booth, Christopher M.

2014-01-01

Purpose: Clinical trials have shown that the addition of chemotherapy to radiation therapy (RT) improves survival in advanced head-and-neck cancer. The objective of this study was to describe the effectiveness of concomitant chemoradiation therapy (C-CRT) in routine practice. Methods and Materials: This was a population-based cohort study. Electronic records of treatment from all provincial cancer centers were linked to a population--based cancer registry to describe the adoption of C-CRT for head-and-neck cancer patients in Ontario, Canada. The study population was then divided into pre- and postadoption cohorts, and their outcomes were compared. Results: Between 1992 and 2008, 18,867 patients hadmore » diagnoses of head-and-neck cancer in Ontario, of whom 7866 (41.7%) were treated with primary RT. The proportion of primary RT cases that received C-CRT increased from 2.2% in the preadoption cohort (1992-1998) to 39.3% in the postadoption cohort (2003-2008). Five-year survival among all primary RT cases increased from 43.6% in the preadoption cohort to 51.8% in the postadoption cohort (P<.001). Over the same period, treatment-related hospital admissions increased significantly, but there was no significant increase in treatment-related deaths. Conclusions: C-CRT was widely adopted in Ontario after 2003, and its adoption was temporally associated with an improvement in survival.« less

Pollen flow in the wildservice tree, Sorbus torminalis (L.) Crantz. I. Evaluating the paternity analysis procedure in continuous populations.

PubMed

Oddou-Muratorio, S; Houot, M-L; Demesure-Musch, B; Austerlitz, F

2003-12-01

The joint development of polymorphic molecular markers and paternity analysis methods provides new approaches to investigate ongoing patterns of pollen flow in natural plant populations. However, paternity studies are hindered by false paternity assignment and the nondetection of true fathers. To gauge the risk of these two types of errors, we performed a simulation study to investigate the impact on paternity analysis of: (i) the assumed values for the size of the breeding male population (NBMP), and (ii) the rate of scoring error in genotype assessment. Our simulations were based on microsatellite data obtained from a natural population of the entomophilous wild service tree, Sorbus torminalis (L.) Crantz. We show that an accurate estimate of NBMP is required to minimize both types of errors, and we assess the reliability of a technique used to estimate NBMP based on parent-offspring genetic data. We then show that scoring errors in genotype assessment only slightly affect the assessment of paternity relationships, and conclude that it is generally better to neglect the scoring error rate in paternity analyses within a nonisolated population.

Helicobacter pylori infection in Canadian and related Arctic Aboriginal populations

PubMed Central

Goodman, Karen J; Jacobson, Kevan; van Zanten, Sander Veldhuyzen

2008-01-01

In 2006, the Canadian Helicobacter Study Group identified Aboriginal communities among Canadian population groups most at risk of Helicobacter pylori-associated disease. The objective of this systematic review was to summarize what is known about the H pylori-associated disease burden in Canadian and related Arctic Aboriginal populations to identify gaps in knowledge. Six health literature databases were systematically searched to identify reports on H pylori prevalence in Canadian population groups, or any topic related to H pylori in Canadian Aboriginals, Alaska Natives or Aboriginals of other Arctic regions. Identified reports were organized by subtopic and summarized in narrative form. Key data from studies of H pylori prevalence in defined populations were summarized in tabular form. A few Arctic Aboriginal communities were represented in the literature: two Canadian Inuit; one Canadian First Nation; two Greenland Inuit; one Russian Chutkotka Native; and several Alaska Native studies. These studies uniformly showed elevated H pylori prevalence; a few studies also showed elevated occurrence of H pylori-related diseases and high rates of treatment failure. Based on the evidence, it would be warranted for clinicians to relax the criteria for investigating H pylori and related diseases in patients from Arctic Aboriginal communities, and to pursue post-therapy confirmation of eradication. Additional community-based research is needed to develop public health policies for reducing H pylori-associated health risks in such communities. PMID:18354758