Epidemiology of invasive fungal diseases among patients with haematological disorders in the Asia-Pacific: a prospective observational study.

PubMed

Hsu, L Y; Lee, D G; Yeh, S P; Bhurani, D; Khanh, B Q; Low, C Y; Norasetthada, L; Chan, T; Kwong, Y L; Vaid, A K; Alejandria, I; Mendoza, M; Chen, C Y; Johnson, A; Tan, T Y

2015-06-01

We conducted a 2-year multicentre prospective observational study to determine the epidemiology of and mortality associated with invasive fungal diseases (IFDs) among patients with haematological disorders in Asia. Eleven institutions from 8 countries/regions participated, with 412 subjects (28.2% possible, 38.3% probable and 33.5% proven IFDs) recruited. The epidemiology of IFDs in participating institutions was similar to Western centres, with Aspergillus spp. (65.9%) or Candida spp. (26.7%) causing the majority of probable and proven IFDs. The overall 30-day mortality was 22.1%. Progressive haematological disorder (odds ratio [OR] 5.192), invasive candidiasis (OR 3.679), and chronic renal disease (OR 6.677) were independently associated with mortality. Copyright © 2015 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Explanation and Elaboration Document for the STROBE-Vet Statement: Strengthening the Reporting of Observational Studies in Epidemiology - Veterinary Extension.

PubMed

O'Connor, A M; Sargeant, J M; Dohoo, I R; Erb, H N; Cevallos, M; Egger, M; Ersbøll, A K; Martin, S W; Nielsen, L R; Pearl, D L; Pfeiffer, D U; Sanchez, J; Torrence, M E; Vigre, H; Waldner, C; Ward, M P

2016-12-01

The STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement was first published in 2007 and again in 2014. The purpose of the original STROBE was to provide guidance for authors, reviewers and editors to improve the comprehensiveness of reporting; however, STROBE has a unique focus on observational studies. Although much of the guidance provided by the original STROBE document is directly applicable, it was deemed useful to map those statements to veterinary concepts, provide veterinary examples and highlight unique aspects of reporting in veterinary observational studies. Here, we present the examples and explanations for the checklist items included in the STROBE-Vet Statement. Thus, this is a companion document to the STROBE-Vet Statement Methods and process document, which describes the checklist and how it was developed. © 2016 The Authors. Zoonoses and Public Health published by Blackwell Verlag GmbH.

Evaluating psychiatric case-control studies using the STROBE (STrengthening the Reporting of OBservational Studies in Epidemiology) statement.

PubMed

Goi, Pedro Domingues; Goi, Julia Domingues; Cordini, Kariny Larissa; Ceresér, Keila Mendes; Rocha, Neusa Sica da

2014-01-01

Case-control studies are important in developing clinical and public health knowledge. The STROBE statement (STrengthening the Reporting of OBservational Studies in Epidemiology) was developed to establish a checklist of items that should be included in articles reporting observational studies. Our aim was to analyze whether the psychiatric case-control articles published in Brazilian journals with CAPES Qualis rating B1/B2 in 2009 conformed with the STROBE statement. Descriptive study on psychiatric papers published in Brazilian journals, within the Postgraduate Medical Program on Psychiatry, at Universidade Federal do Rio Grande do Sul. All psychiatric case-control studies from Brazilian Qualis B1/B2 journals of psychiatry, neurology and public health in 2009 were analyzed. The four most specific items of the STROBE statement were used to evaluate whether these studies fitted within the case-control parameters: 1) selection of cases and controls; 2) controlling for bias; 3) statistical analysis; and 4) presentation of results. Sixteen case-control studies were identified, of which eleven (68.75%) were in psychiatry-focused journals. From analysis using the STROBE statement, all of the articles conformed with item 1; two (12.5%) completely conformed with item 2; none completely conformed with item 3; and only three (18.8%) conformed with item 4. The case-control studies analyzed here did not completely conform with the four STROBE statement items for case-control design. In view of the inadequate methodology of the published studies, these findings justify focusing on research and methodology and expanding the investigations on adherence of studies to their designs.

Methods and Processes of Developing the Strengthening the Reporting of Observational Studies in Epidemiology-Veterinary (STROBE-Vet) Statement.

PubMed

Sargeant, J M; O'Connor, A M; Dohoo, I R; Erb, H N; Cevallos, M; Egger, M; Ersbøll, A K; Martin, S W; Nielsen, L R; Pearl, D L; Pfeiffer, D U; Sanchez, J; Torrence, M E; Vigre, H; Waldner, C; Ward, M P

2016-12-01

Reporting of observational studies in veterinary research presents challenges that often are not addressed in published reporting guidelines. Our objective was to develop an extension of the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement that addresses unique reporting requirements for observational studies in veterinary medicine related to health, production, welfare, and food safety. We conducted a consensus meeting with 17 experts in Mississauga, Canada. Experts completed a premeeting survey about whether items in the STROBE statement should be modified or added to address unique issues related to observational studies in animal species with health, production, welfare, or food safety outcomes. During the meeting, each STROBE item was discussed to determine whether or not rewording was recommended, and whether additions were warranted. Anonymous voting was used to determine consensus. Six items required no modifications or additions. Modifications or additions were made to the STROBE items 1 (title and abstract), 3 (objectives), 5 (setting), 6 (participants), 7 (variables), 8 (data sources and measurement), 9 (bias), 10 (study size), 12 (statistical methods), 13 (participants), 14 (descriptive data), 15 (outcome data), 16 (main results), 17 (other analyses), 19 (limitations), and 22 (funding). The methods and processes used were similar to those used for other extensions of the STROBE statement. The use of this STROBE statement extension should improve reporting of observational studies in veterinary research by recognizing unique features of observational studies involving food-producing and companion animals, products of animal origin, aquaculture, and wildlife.

Methods and Processes of Developing the Strengthening the Reporting of Observational Studies in Epidemiology - Veterinary (STROBE-Vet) Statement.

PubMed

Sargeant, J M; O'Connor, A M; Dohoo, I R; Erb, H N; Cevallos, M; Egger, M; Ersbøll, A K; Martin, S W; Nielsen, L R; Pearl, D L; Pfeiffer, D U; Sanchez, J; Torrence, M E; Vigre, H; Waldner, C; Ward, M P

2016-11-01

Reporting of observational studies in veterinary research presents challenges that often are not addressed in published reporting guidelines. To develop an extension of the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement that addresses unique reporting requirements for observational studies in veterinary medicine related to health, production, welfare, and food safety. Consensus meeting of experts. Mississauga, Canada. Seventeen experts from North America, Europe, and Australia. Experts completed a pre-meeting survey about whether items in the STROBE statement should be modified or added to address unique issues related to observational studies in animal species with health, production, welfare, or food safety outcomes. During the meeting, each STROBE item was discussed to determine whether or not rewording was recommended and whether additions were warranted. Anonymous voting was used to determine consensus. Six items required no modifications or additions. Modifications or additions were made to the STROBE items 1 (title and abstract), 3 (objectives), 5 (setting), 6 (participants), 7 (variables), 8 (data sources/measurement), 9 (bias), 10 (study size), 12 (statistical methods), 13 (participants), 14 (descriptive data), 15 (outcome data), 16 (main results), 17 (other analyses), 19 (limitations), and 22 (funding). The methods and processes used were similar to those used for other extensions of the STROBE statement. The use of this STROBE statement extension should improve reporting of observational studies in veterinary research by recognizing unique features of observational studies involving food-producing and companion animals, products of animal origin, aquaculture, and wildlife. Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Epidemiology and outcomes of out-of-hospital cardiac arrest in Qatar: A nationwide observational study.

PubMed

Irfan, Furqan B; Bhutta, Zain Ali; Castren, Maaret; Straney, Lahn; Djarv, Therese; Tariq, Tooba; Thomas, Stephen Hodges; Alinier, Guillaume; Al Shaikh, Loua; Owen, Robert Campbell; Al Suwaidi, Jassim; Shuaib, Ashfaq; Singh, Rajvir; Cameron, Peter Alistair

2016-11-15

Out-of-hospital cardiac arrest (OHCA) studies from the Middle East and Asian region are limited. This study describes the epidemiology, emergency health services, and outcomes of OHCA in Qatar. This was a prospective nationwide population-based observational study on OHCA patients in Qatar according to Utstein style guidelines, from June 2012 to May 2013. Data was collected from various sources; the national emergency medical service, 4 emergency departments, and 8 public hospitals. The annual crude incidence of presumed cardiac OHCA attended by EMS was 23.5 per 100,000. The age-sex standardized incidence was 87.8 per 100,000 population. Of the 447 OHCA patients included in the final analysis, most were male (n=360, 80.5%) with median age of 51years (IQR=39-66). Frequently observed nationalities were Qatari (n=89, 19.9%), Indian (n=74, 16.6%) and Nepalese (n=52, 11.6%). Bystander cardiopulmonary resuscitation (CPR) was carried out in 92 (20.6%) OHCA patients. Survival rate was 8.1% (n=36) and multivariable logistic regression indicated that initial shockable rhythm (OR 13.4, 95% CI 5.4-33.3, p=0.001) was associated with higher odds of survival while male gender (OR 0.27, 95% CI 0.1-0.8, p=0.01) and advanced cardiac life support (ACLS) (OR 0.15, 95% CI 0.04-0.5, p=0.02) were associated with lower odds of survival. Standardized incidence and survival rates were comparable to Western countries. Although expatriates comprise more than 80% of the population, Qataris contributed 20% of the total cardiac arrests observed. There are significant opportunities to improve outcomes, including community-based CPR and defibrillation training. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Some Observations on the Diagnosis and Epidemiology of Leptospirosis in Swine

PubMed Central

Mitchell, D.; Robertson, A.; Corner, A. H.; Boulanger, P.

1966-01-01

The results of combined epidemiological, clinical, serological, bacteriological and histopathological studies following an outbreak of disease caused by L. pomona on a farm stocked with cattle, sheep, pigs, goats and horses maintained for experimental purposes, are reported. The incidence of infection was high in horses, cattle and pigs. A few low titres were seen in sheep. The goats were not infected. Apart from a single bovine abortion all the clinical symptoms observed occurred in pregnant sows. Seven of these aborted or gave birth to stillborn pigs within a six week period. Fifteen species of wildlife were trapped or shot on the farm during the year following the outbreak. L. pomona was isolated from four skunks and a porcupine. Epidemiological studies indicated that wildlife reservoir hosts were the primary source of infection for the domestic livestock. Leptospiruria and the serological response were studied in a group of eight infected sows. Microscopic agglutination titres of 102 or less could not be associated with leptospiruria and the duration of leptospiruria was found to range from a few weeks to over two years in individual sows. Direct dark-field examination of urine proved superior to guinea-pig inoculation as a method of detecting leptospiruria and it is suggested that the former technique could be adopted with advantage as a routine aid to diagnosis. PMID:4226190

Epidemiological profile of sports-related knee injuries in northern India: An observational study at a tertiary care centre.

PubMed

John, R; Dhillon, M S; Syam, K; Prabhakar, S; Behera, P; Singh, H

2016-01-01

Sports-related knee injuries occur commonly in athletes. However, there is no published epidemiological study from India till date. The purpose of this study was to identify common injuries sustained by Indian athletes participating in different sports and to study various associated demographic features. A secondary objective was to investigate different factors, which may affect return to sport by the athlete. Cross-sectional study (observational study). Sports injury clinic, PGIMER, Chandigarh. Out of 465 athletes who presented to us with sports-related knee injuries over a 5-year period, 363 athletes (from 24 different sports) with complete records were identified. Data were analysed for demographic features, type of sport, mechanism of injury, injury scenario, athlete's level of play, injury duration at presentation, injury patterns and type of management. Telephonic interviews were conducted with each athlete to enquire about return to sport and time lost in sport due to the knee injury. Factors associated with return to sport were investigated using statistical tests of association. Soccer was found to be the most common sport associated with knee injuries accounting for 30.6% of the injuries followed by kabaddi (20.9%). The most common mechanism was non-contact injury (64.4%). Competitive injuries were found to be significantly more than practice/training injuries (p < 0.0001). The most common injuries noted were ACL tears (n = 314) followed by meniscus injuries (n = 284) and the most common combination of injuries were an ACL tear with medial meniscus tear (n = 163). Only 39.8% of the athletes returned to sport. Mean duration of time lost in sport among those who returned to sport was 8.84 months. Return to sport was significantly associated with body mass index, level of competitiveness of the athlete and type of management (p = 0.017, 0.045 and <0.0001, respectively). Knee injuries take a huge toll on an athlete's career as observed in this

Multiple Imputation for Incomplete Data in Epidemiologic Studies

PubMed Central

Harel, Ofer; Mitchell, Emily M; Perkins, Neil J; Cole, Stephen R; Tchetgen Tchetgen, Eric J; Sun, BaoLuo; Schisterman, Enrique F

2018-01-01

Abstract Epidemiologic studies are frequently susceptible to missing information. Omitting observations with missing variables remains a common strategy in epidemiologic studies, yet this simple approach can often severely bias parameter estimates of interest if the values are not missing completely at random. Even when missingness is completely random, complete-case analysis can reduce the efficiency of estimated parameters, because large amounts of available data are simply tossed out with the incomplete observations. Alternative methods for mitigating the influence of missing information, such as multiple imputation, are becoming an increasing popular strategy in order to retain all available information, reduce potential bias, and improve efficiency in parameter estimation. In this paper, we describe the theoretical underpinnings of multiple imputation, and we illustrate application of this method as part of a collaborative challenge to assess the performance of various techniques for dealing with missing data (Am J Epidemiol. 2018;187(3):568–575). We detail the steps necessary to perform multiple imputation on a subset of data from the Collaborative Perinatal Project (1959–1974), where the goal is to estimate the odds of spontaneous abortion associated with smoking during pregnancy. PMID:29165547

Event-based internet biosurveillance: relation to epidemiological observation

PubMed Central

2012-01-01

Background The World Health Organization (WHO) collects and publishes surveillance data and statistics for select diseases, but traditional methods of gathering such data are time and labor intensive. Event-based biosurveillance, which utilizes a variety of Internet sources, complements traditional surveillance. In this study we assess the reliability of Internet biosurveillance and evaluate disease-specific alert criteria against epidemiological data. Methods We reviewed and compared WHO epidemiological data and Argus biosurveillance system data for pandemic (H1N1) 2009 (April 2009 – January 2010) from 8 regions and 122 countries to: identify reliable alert criteria among 15 Argus-defined categories; determine the degree of data correlation for disease progression; and assess timeliness of Internet information. Results Argus generated a total of 1,580 unique alerts; 5 alert categories generated statistically significant (p < 0.05) correlations with WHO case count data; the sum of these 5 categories was highly correlated with WHO case data (r = 0.81, p < 0.0001), with expected differences observed among the 8 regions. Argus reported first confirmed cases on the same day as WHO for 21 of the first 64 countries reporting cases, and 1 to 16 days (average 1.5 days) ahead of WHO for 42 of those countries. Conclusion Confirmed pandemic (H1N1) 2009 cases collected by Argus and WHO methods returned consistent results and confirmed the reliability and timeliness of Internet information. Disease-specific alert criteria provide situational awareness and may serve as proxy indicators to event progression and escalation in lieu of traditional surveillance data; alerts may identify early-warning indicators to another pandemic, preparing the public health community for disease events. PMID:22709988

Helminths and HIV infection: epidemiological observations on immunological hypotheses

PubMed Central

BROWN, M; MAWA, P A; KALEEBU, P; ELLIOTT, A M

2006-01-01

Parasitic helminths have co-evolved with the mammalian immune system. Current hypotheses suggest that immunological stimulation in the presence of helminths is balanced by immuno-regulation and by the broad spectrum of mechanisms possessed by helminths for countering the host immune response. The degree to which this balance is perfected, and the mechanisms by which this is achieved, vary between helminth species; we suggest that this is reflected not only in the degree of pathology induced by helminths but also in a variety of relationships with HIV infection and HIV disease. Available epidemiological data regarding interactions between helminths and HIV are largely observational; results are variable and generally inconclusive. Well designed, controlled intervention studies are required to provide definitive information on the species-specific nature of these interactions and on the advantages, disadvantages and optimal timing of de-worming in relation to HIV infection. PMID:17042933

Assessing the connection between organophosphate pesticide poisoning and mental health: A comparison of neuropsychological symptoms from clinical observations, animal models and epidemiological studies.

PubMed

Stallones, Lorann; Beseler, Cheryl L

2016-01-01

Psychiatry and psychology are beginning to recognize the importance of lead, mercury and heavy metals as causal partners in the development of mental disorders. Further, mental health researchers and clinicians are embracing the idea that the combined effects of genetics and environmental exposures can result in perturbations in brain neurochemistry leading to psychiatric disorders. The purpose of this review is to examine the biological foundations for the epidemiological observations previously identified by reviewing the toxicology literature and relating it to epidemiological studies addressing the role of poisoning with organophosphate pesticides (OPs) in neurobehavioral and neuropsychological disorders. The goal of this review is to raise awareness in the mental health community about the possibility that affective disorders might be the result of contributions from environmental and occupational pesticide poisoning. Copyright © 2015 Elsevier Ltd. All rights reserved.

TCDD and cancer: A critical review of epidemiologic studies

PubMed Central

Boffetta, Paolo; Mundt, Kenneth A; Adami, Hans-Olov; Cole, Philip; Mandel, Jack S

2011-01-01

The authors reviewed the epidemiologic studies on exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and cancer risk, published since the last full-scale review made by the International Agency for Research on Cancer Monographs program in 1997. The update of a cohort of US herbicide producers generated negative results overall; the internal analysis provided evidence of an increased “all-cancer” risk in the highest exposure category, with a statistically significant exposure-response association in some of the many analyses performed.The update of a similar Dutch cohort did not confirm the previously observed association with TCDD exposure. The updated surveillance of the Seveso population provided evidence of increased all-cancer mortality 15-20 years after exposure among those living in the most contaminated area but might also reflect random variation, as overall excesses in the most recent follow-up were not observed. Corresponding data on cancer incidence offer little support to the mortality results. Updated results from cohort studies of Vietnam veterans potentially exposed to TCDD did not consistently suggest an increased risk of cancer. Results of additional, smaller studies of other occupational groups potentially exposed to TCDD, and of community-based case-control studies, did not provide consistent evidence of an increased cancer risk. In conclusion, recent epidemiological evidence falls far short of conclusively demonstrating a causal link between TCDD exposure and cancer risk in humans. The emphasis on results for overall cancer risk—rather than risk for specific neoplasms—is notjustified on epidemiologic grounds and is nota reason for ignoring the weaknesses of the available evidence. PMID:21718216

HIV and herpes simplex virus type 2 epidemiological synergy: misguided observational evidence? A modelling study.

PubMed

Omori, Ryosuke; Nagelkerke, Nico; Abu-Raddad, Laith J

2017-12-04

To investigate whether observational studies of HIV and herpes simplex virus type 2 (HSV-2) infections have the capacity to assess the HIV/HSV-2 epidemiological synergy. An individual-based Monte Carlo model was used to simulate HIV/HSV-2 epidemics in two scenarios: no HIV/HSV-2 biological interaction and HSV-2 seropositivity enhancing HIV acquisition. Cross-sectional observational studies were simulated by sampling individuals from the population to assess resulting crude and adjusted ORs of the HIV/HSV-2 association. Meta-analyses were conducted to estimate the pooled mean ORs. Impact of under-reporting of sexual behaviour and miscapture of high-risk individuals was assessed through sensitivity analyses. Assuming no HIV/HSV-2 biological interaction, the crude HIV/HSV-2 OR ranged between 1.38 and 9.93, with a pooled mean of 6.45 (95% CI 5.81 to 7.17). Adjustment for the number of sexual partners over last year, over lifetime and for both partner numbers simultaneously reduced the mean OR to 5.45 (95% CI 4.90 to 6.06), 3.70 (95% CI 3.32 to 4.12) and 3.54 (95% CI 3.17 to 3.94), respectively. Assuming HIV/HSV-2 biological interaction, the crude OR ranged between 3.44 and 9.95, with a pooled mean of 8.05 (95% CI 7.14 to 9.07). The adjustments reduced the mean OR to 7.00 (95% CI 6.21 to 7.90), 3.76 (95% CI 3.32 to 4.25) and 3.68 (95% CI 3.25 to 4.17), respectively. Under-reporting of partners reduced the confounder-adjustment effects. Miscapture of high-risk individuals considerably lowered the estimated ORs. It is difficult to control for sexual-behaviour confounding in observational studies. The observed HIV/HSV-2 association appears more consistent with two infections sharing the same mode of transmission, rather than with HSV-2 enhancing HIV acquisition. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

NASA Remote Sensing Data for Epidemiological Studies

NASA Technical Reports Server (NTRS)

Maynard, Nancy G.; Vicente, G. A.

2002-01-01

In response to the need for improved observations of environmental factors to better understand the links between human health and the environment, NASA has established a new program to significantly improve the utilization of NASA's diverse array of data, information, and observations of the Earth for health applications. This initiative, lead by Goddard Space Flight Center (GSFC) has the following goals: (1) To encourage interdisciplinary research on the relationships between environmental parameters (e.g., rainfall, vegetation) and health, (2) Develop practical early warning systems, (3) Create a unique system for the exchange of Earth science and health data, (4) Provide an investigator field support system for customers and partners, (5) Facilitate a system for observation, identification, and surveillance of parameters relevant to environment and health issues. The NASA Environment and Health Program is conducting several interdisciplinary projects to examine applications of remote sensing data and information to a variety of health issues, including studies on malaria, Rift Valley Fever, St. Louis Encephalitis, Dengue Fever, Ebola, African Dust and health, meningitis, asthma, and filariasis. In addition, the NASA program is creating a user-friendly data system to help provide the public health community with easy and timely access to space-based environmental data for epidemiological studies. This NASA data system is being designed to bring land, atmosphere, water and ocean satellite data/products to users not familiar with satellite data/products, but who are knowledgeable in the Geographic Information Systems (GIS) environment. This paper discusses the most recent results of the interdisciplinary environment-health research projects and provides an analysis of the usefulness of the satellite data to epidemiological studies. In addition, there will be a summary of presently-available NASA Earth science data and a description of how it may be obtained.

Hospital Morbidity Database for Epidemiological Studies on Churg-Strauss Syndrome.

PubMed

Kanecki, Krzysztof; Nitsch-Osuch, Aneta; Gorynski, Paweł; Tarka, Patryk; Tyszko, Piotr

2017-01-01

Churg-Strauss syndrome or more accurately eosinophilic granulomatosis with polyangiitis (EGPA) is a small-vessel necrotizing vasculitis with a characteristic late-onset allergic rhinitis and asthma. The use of hospital morbidity database is an important element of the epidemiological analysis of this rare disease. The present study was undertaken to assess the incidence of EGPA and factors related to its epidemiology in Poland; the first analysis of the kind in Poland, enabling a comparison in the European context. This is a retrospective, population-based study using hospital discharge records with EGPA diagnosis, collected for a National Institute of Public Health survey covering the period from 2008 to 2013. The group consisted of 344 patients (206 females and 138 males) with the first-time hospitalization for EGPA. The major findings are that the annual incidence of EGPA in Poland was 1.5 per million (95% confidence intervals: 1.2-1.8), with the point prevalence of 8.8 per million at the end of 2013. A greater incidence of EGPA was observed in the regions with urban predominance. We conclude that discharge records may be a useful element of epidemiological studies on EGPA.

Genotyping of Mycobacterium tuberculosis: application in epidemiologic studies

PubMed Central

Kato-Maeda, Midori; Metcalfe, John Z.; Flores, Laura

2014-01-01

Genotyping is used to track specific isolates of Mycobacterium tuberculosis in a community. It has been successfully used in epidemiologic research (termed ‘molecular epidemiology’) to study the transmission dynamics of TB. In this article, we review the genetic markers used in molecular epidemiologic studies including the use of whole-genome sequencing technology. We also review the public health application of molecular epidemiologic tools. PMID:21366420

Methods and processes of developing the strengthening the reporting of observational studies in epidemiology - veterinary (STROBE-Vet) statement.

PubMed

Sargeant, J M; O'Connor, A M; Dohoo, I R; Erb, H N; Cevallos, M; Egger, M; Ersbøll, A K; Martin, S W; Nielsen, L R; Pearl, D L; Pfeiffer, D U; Sanchez, J; Torrence, M E; Vigre, H; Waldner, C; Ward, M P

2016-11-01

The reporting of observational studies in veterinary research presents many challenges that often are not adequately addressed in published reporting guidelines. To develop an extension of the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement that addresses unique reporting requirements for observational studies in veterinary medicine related to health, production, welfare, and food safety. A consensus meeting of experts was organized to develop an extension of the STROBE statement to address observational studies in veterinary medicine with respect to animal health, animal production, animal welfare, and food safety outcomes. Consensus meeting May 11-13, 2014 in Mississauga, Ontario, Canada. Seventeen experts from North America, Europe, and Australia attended the meeting. The experts were epidemiologists and biostatisticians, many of whom hold or have held editorial positions with relevant journals. Prior to the meeting, 19 experts completed a survey about whether they felt any of the 22 items of the STROBE statement should be modified and if items should be added to address unique issues related to observational studies in animal species with health, production, welfare, or food safety outcomes. At the meeting, the participants were provided with the survey responses and relevant literature concerning the reporting of veterinary observational studies. During the meeting, each STROBE item was discussed to determine whether or not re-wording was recommended, and whether additions were warranted. Anonymous voting was used to determine whether there was consensus for each item change or addition. The consensus was that six items needed no modifications or additions. Modifications or additions were made to the STROBE items numbered: 1 (title and abstract), 3 (objectives), 5 (setting), 6 (participants), 7 (variables), 8 (data sources/measurement), 9 (bias), 10 (study size), 12 (statistical methods), 13 (participants), 14

An Observational Epidemiological Study of Exercise-induced Rhabdomyolysis Causing Acute Kidney Injury: A Single-center Experience.

PubMed

Jabur, W L; Nasa, P; Mohammed, K A; Kulkarni, A; Tomaraei, S N

2018-01-01

Exercise-induced rhabdomyolysis (EIR) is an uncommon cause of severe rhabdomyolysis and a very rare cause of acute kidney injury (AKI). A prospective observational study of 25 patients diagnosed with EIR was conducted in a multispecialty hospital in Dubai, from 2009 to 2015. Five out of 25 patients experienced AKI necessitating temporary renal replacement therapy. The initial presentation, biochemical parameters, and clinical course of patients were monitored, to understand epidemiology and risk factors for the development of AKI. There was male preponderance (4 out of 5 patients), higher rate of systemic symptoms (all 5 patients) versus 60% in NRAKI), oligo-anuria (all 5 patients), compartment syndrome (3 out \\of 5) and severe dehydration seen in patients with RAKI group. On laboratory evaluation, there was higher rise in creatinine kinase (CK) enzyme, serum and urine myoglobin levels impaired renal function on presentation, hyperuricemia, high D-dimer level, PCV of more than 55%, found to be associated with RAKI as compared to NRAKI group. Hematuria by positive urine dipstick with absent red blood cells on urinalysis, is an insensitive tool as was present in only 62% and 43% of RAKI and NRAKI groups, respectively. It was also observed that delayed pesentation for medical care, metabolic acidosis, were commonly associated with AKI. All patients with RAKI required RRT for a comparable period of time (3-4 weeks). In all of them, no deterioration or relapse reported on follow-up of 3 months.

Prospective observational study of midtarsal joint sprain: Epidemiological and ultrasonographic analysis.

PubMed

Thiounn, A; Szymanski, C; Lalanne, C; Soudy, K; Demondion, X; Maynou, C

2016-09-01

Foot and ankle injuries (FAI) are very common, with about 6000 cases per day in France. Unlike lateral ankle sprain (LAS), the diagnosis of midtarsal joint sprain (MJS, also known as Chopart's joint sprain) is not widely known. This prospective study aims to detail the epidemiology of MJS and compare it to LAS. The study was conducted within our institution over a period of 16 months. Patients with clinical signs predictive of MJS without radiographic bone lesion underwent ultrasound assessment. MJS was diagnosed in case of at least 1 lesion of the dorsal midtarsal joint ligaments. A total of 2412 patients consulted for FAI; 188 had clinical and radiographic criteria for ultrasound examination. Eighty-two cases of MJS were diagnosed (3.4% of FAIs). Sports injuries were more frequent in MJS (P=0.04), and mechanisms more varied than in LAS, with inversion injury in 75% of cases and plantar hyperflexion in 22%. Sprain was severe in 70% of cases, with complete ligament tear. Clinical and ultrasound analyses correlated in only 40% of cases of MJS, versus 98% for LAS. MJS is frequent, difficult to diagnose clinically, and often severe. Clinical presentation and injury mechanisms differ from ankle sprain. Ultrasound seems to be an indispensable tool in diagnosis. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Cocoa Polyphenols: Evidence from Epidemiological Studies.

PubMed

Matsumoto, Chisa

2018-01-01

Accumulating evidence suggests potential preventive effects of chocolate/cocoa on the risk of cardio vascular disease (CVD). However, cocoa products also contain high levels of sugar and fat, which increase CVD risk factors. Even, the identity of the substance in chocolate/cocoa that has a favorable effect on CVD and CVD risk factors remains unclear, growing evidence from experimental studies suggests that cocoa polyphenols might be a major contributor to cardiovascular-protective effects. However, epidemiological studies, which are necessary to evaluate an association between the risk of CVD and cocoa polyphenol, remain sparse. We will discuss recent evidence regarding the association between cocoa polyphenol consumption and the risks of CVD and its risk factors by reviewing recent epidemiological studies. We shall also provide some guidance for patient counseling and will discuss the public health implications for recommending cocoa polyphenol consumption to prevent CVD. Epidemiological studies evaluating the association between cocoa polyphenol itself and the risk of CVD are sparse. However, evidence from limited epidemiological studies suggests that cocoa polyphenol consumption may lower the risk of CVD. Given the potential adverse effects of the consumption of cocoa products with high fat and sugar and the fact that the most appropriate dose of cocoa polyphenol for cardio-protective effects has not yet been established, health care providers should remain cautious about recommending cocoa/cocoa polyphenol consumption to their patients to reduce the risk of CVD, taking the characteristics of individual patients into careful consideration. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Overview of the epidemiology methods and applications: strengths and limitations of observational study designs.

PubMed

Colditz, Graham A

2010-01-01

that investigated the association between participation in breast cancer screening programs and breast cancer mortality. The authors showed that if one assumes noncompliance with mammography (approaching 30%) and 20% of the control group is screened, then the benefit of mammography in terms of reduced mortality is comparable in randomized, controlled trials and epidemiologic studies after adjusting for nonadherence (Demissie et al., 1998). Thus, the different designs fundamentally measure different constructs of the impact of screening. Zelen (1988) considered the challenges of primary prevention trials and addressed both compliance and models of carcinogenesis as major impediments to the use of randomized, controlled trials to evaluate cancer prevention strategies. It is important to contrast these issues in both treatment trials and prevention trials. In treatment trials, recently diagnosed patients, who are often in life-threatening situations, are typically offered the option to participate in a trial of a new therapy compared with standard therapy or placebo. Compliance or adherence to therapy is usually very high among these highly motivated patients and their outcomes are generally in the short- to mid-term. In contrast, prevention trials recruit large numbers of healthy participants, offer them a therapy, and then follow them over many years because the chronic diseases being prevented are relatively rare. With substantial noncompliance (often in the range of 20% to 40% over the duration of the trial), an intention-to-treat analysis is no longer unbiased, but rather gives a biased estimate of the effect, typically underestimating the magnitude of the association that is seen in observation studies in which those participants who have had exposure to a particular lifestyle component are compared with those without such an exposure. There are additional challenges for nutritional interventions, including the timing of diet as a preventive agent in the disease

Use of benzodiazepine and risk of cancer: A meta-analysis of observational studies.

PubMed

Kim, Hong-Bae; Myung, Seung-Kwon; Park, Yon Chul; Park, Byoungjin

2017-02-01

Several observational epidemiological studies have reported inconsistent results on the association between the use of benzodiazepine and the risk of cancer. We investigated the association by using a meta-analysis. We searched PubMed, EMBASE, and the bibliographies of relevant articles to locate additional publications in January 2016. Three evaluators independently reviewed and selected eligible studies based on predetermined selection criteria. Of 796 articles meeting our initial criteria, a total of 22 observational epidemiological studies with 18 case-control studies and 4 cohort studies were included in the final analysis. Benzodiazepine use was significantly associated with an increased risk of cancer (odds ratio [OR] or relative risk [RR] 1.19; 95% confidence interval 1.16-1.21) in a random-effects meta-analysis of all studies. Subgroup meta-analyses by various factors such as study design, type of case-control study, study region, and methodological quality of study showed consistent findings. Also, a significant dose-response relationship was observed between the use of benzodiazepine and the risk of cancer (p for trend <0.01). The current meta-analysis of observational epidemiological studies suggests that benzodiazepine use is associated with an increased risk of cancer. © 2016 UICC.

ADHD in the Arab World: A Review of Epidemiologic Studies

ERIC Educational Resources Information Center

Farah, Lynn G.; Fayyad, John A.; Eapen, Valsamma; Cassir,Youmna; Salamoun, Mariana M.; Tabet, Caroline C.; Mneimneh, Zeina N.; Karam, Elie G.

2009-01-01

Objective: Epidemiological studies on psychiatric disorders are quite rare in the Arab World. This article reviews epidemiological studies on ADHD in all the Arab countries. Method: All epidemiological studies on ADHD conducted from 1966 through th present were reviewed. Samples were drawn from the general community, primary care clinical…

Community Engagement in Epidemiological Research

PubMed Central

Sapienza, Jessica N.; Corbie-Smith, Giselle; Keim, Sarah; Fleischman, Alan R.

2007-01-01

Objectives Engaging communities has become a critical aspect of planning and implementing health research. The role community engagement should play in epidemiological and observational research remains unclear since much of this research is not directly generated by community concerns and is not interventional in nature. The National Children's Study (NCS), an observational longitudinal study of 100,000 children and their families, provides a model to help guide the development of community engagement strategies in epidemiologic research. Methodology This manuscript describes community engagement activities of the NCS during the planning phases of the study. Results There are many challenges of community engagement in epidemiologic research particularly before the actual research sites are determined. After communities of interest are designated many further issues must be resolved, including: defining the specific community, determining which residents or institutions represent the identified community, and developing trust and rapport through respectful engagement. Conclusions Community engagement is critical to the long-term success of any longitudinal epidemiologic study. A partnership with the community should be formed to ensure mutual respect and the establishment of an enduring relationship. Genuine community engagement offers the hope of enhancing recruitment, retention, and participant satisfaction. PMID:17512886

Epidemiology and diagnostic and therapeutic management of febrile seizures in the Italian pediatric emergency departments: A prospective observational study.

PubMed

Vitaliti, Giovanna; Castagno, Emanuele; Ricceri, Fulvio; Urbino, Antonio; Di Pianella, Alberto Verrotti; Lubrano, Riccardo; Caramaschi, Elisa; Prota, Maurizio; Pulvirenti, Rita Maria; Ajovalasit, Patrizia; Signorile, Giuseppe; Navone, Carla; La Bianca, Maria Rosaria; Villani, Alberto; Corsello, Giovanni; Falsaperla, Raffaele

2017-01-01

Febrile seizures (FS) involve 2-5% of the paediatric population, among which Complex FS (CFS) account for one third of accesses for FS in Emergency Departments (EDs). The aim of our study was to define the epidemiology, the clinical, diagnostic and therapeutic approach to FS and CFSs in the Italian EDs. A multicenter prospective observational study was performed between April 2014 and March 2015. Patients between 1 and 60 months of age, randomly accessing to ED for ongoing FS or reported FS at home were included. Demographic features and diagnostic-therapeutic follow-up were recorded. FS were categorized in simple (<10min), prolonged (10-30min) and status epilepticus (>30min). The study population consisted of 268 children. Most of the children experienced simple FS (71.65%). Among the 68 (25.37%) patients with complex FS, 11 were 6-12 month-old, accounting for 45.83% of all the infants with FS in the younger age group. No therapy has been administered at home in 76.12% patients; 23.51% of them received endorectal diazepam and only 1 patient received buccal midazolam. At arrival at ED, no therapy was necessary for 70.52% patients; 50.63% received endorectal diazepam and 17.72% an i.v. bolus of midazolam. Blood tests and acid-base balanced were performed respectively in 82.09% of cases. An electroencephalogram at ED was performed in 21.64% of patients. Neuroimagings were done in 3.73% of cases. A neurologic consultation was asked for 36 patients (13.43%). this is the first study assessing epidemiologic characteristics of FS in the Italian pediatric population, evidencing a higher prevalence of CFSs in children younger than 12 months of age and opening a new research scenario on the blood brain barrier vulnerability. On a national level, our study showed the need for a diagnostic standardized work-up to improve the cost/benefit ratio on CFS management. Copyright © 2016 Elsevier B.V. All rights reserved.

Examination of Different Exposure Metrics in an Epidemiological Study

EPA Science Inventory

Epidemiological studies of air pollution have traditionally relied upon measurements of ambient concentration from central-site monitoring stations as surrogates of population exposures. However, depending on the epidemiological study design, this approach may introduce exposure...

Embedding clinical interventions into observational studies

PubMed Central

Newman, Anne B.; Avilés-Santa, M. Larissa; Anderson, Garnet; Heiss, Gerardo; Howard, Wm. James; Krucoff, Mitchell; Kuller, Lewis H.; Lewis, Cora E.; Robinson, Jennifer G.; Taylor, Herman; Treviño, Roberto P.; Weintraub, William

2017-01-01

Novel approaches to observational studies and clinical trials could improve the cost-effectiveness and speed of translation of research. Hybrid designs that combine elements of clinical trials with observational registries or cohort studies should be considered as part of a long-term strategy to transform clinical trials and epidemiology, adapting to the opportunities of big data and the challenges of constrained budgets. Important considerations include study aims, timing, breadth and depth of the existing infrastructure that can be leveraged, participant burden, likely participation rate and available sample size in the cohort, required sample size for the trial, and investigator expertise. Community engagement and stakeholder (including study participants) support are essential for these efforts to succeed. PMID:26611435

COLLABORATION ON NHEERL EPIDEMIOLOGY STUDIES

EPA Science Inventory

This task will continue ORD's efforts to develop a biologically plausible, quantitative health risk model for particulate matter (PM) based on epidemiological, toxicological, and mechanistic studies using matched exposure assessments. The NERL, in collaboration with the NHEERL, ...

Circular epidemiology.

PubMed

Kuller, L H

1999-11-01

Circular epidemiology can be defined as the continuation of specific types of epidemiologic studies beyond the point of reasonable doubt of the true existence of an important association or the absence of such an association. Circular epidemiology is an extreme example of studies of the consistency of associations. A basic problem for epidemiology is the lack of a systematic approach to acquiring new knowledge to reach a goal of improving public health and preventive medicine. For epidemiologists, research support unfortunately is biased toward the continued study of already proven hypotheses. Circular epidemiology, however, freezes at one point in the evolution of epidemiologic studies, failing to move from descriptive to analytical case-control and longitudinal studies, for example, to experimental, clinical trials. Good epidemiology journals are filled with very well-conducted epidemiologic studies that primarily repeat the obvious or are variations on the theme.

[Eco-epidemiology: towards epidemiology of complexity].

PubMed

Bizouarn, Philippe

2016-05-01

In order to solve public health problems posed by the epidemiology of risk factors centered on the individual and neglecting the causal processes linking the risk factors with the health outcomes, Mervyn Susser proposed a multilevel epidemiology called eco-epidemiology, addressing the interdependence of individuals and their connection with molecular, individual, societal, environmental levels of organization participating in the causal disease processes. The aim of this epidemiology is to integrate more than a level of organization in design, analysis and interpretation of health problems. After presenting the main criticisms of risk-factor epidemiology focused on the individual, we will try to show how eco-epidemiology and its development could help to understand the need for a broader and integrative epidemiology, in which studies designed to identify risk factors would be balanced by studies designed to answer other questions equally vital to public health. © 2016 médecine/sciences – Inserm.

EPIDEMIOLOGIC STUDIES OF DISINFECTANTS AND DISINFECTANT BY-PRODUCTS

EPA Science Inventory

This article provides a review of the epidemiologic evidence for human health effects that may be associated with the disinfection of drinking water. An epidemiologic study attempts to link human health effects with exposure to a specific agent (e.g., DBCM), agents (e.g., THMs or...

Embedding clinical interventions into observational studies.

PubMed

Newman, Anne B; Avilés-Santa, M Larissa; Anderson, Garnet; Heiss, Gerardo; Howard, Wm James; Krucoff, Mitchell; Kuller, Lewis H; Lewis, Cora E; Robinson, Jennifer G; Taylor, Herman; Treviño, Roberto P; Weintraub, William

2016-01-01

Novel approaches to observational studies and clinical trials could improve the cost-effectiveness and speed of translation of research. Hybrid designs that combine elements of clinical trials with observational registries or cohort studies should be considered as part of a long-term strategy to transform clinical trials and epidemiology, adapting to the opportunities of big data and the challenges of constrained budgets. Important considerations include study aims, timing, breadth and depth of the existing infrastructure that can be leveraged, participant burden, likely participation rate and available sample size in the cohort, required sample size for the trial, and investigator expertise. Community engagement and stakeholder (including study participants) support are essential for these efforts to succeed. Copyright © 2015. Published by Elsevier Inc.

Mendelian randomization in nutritional epidemiology

PubMed Central

Qi, Lu

2013-01-01

Nutritional epidemiology aims to identify dietary and lifestyle causes for human diseases. Causality inference in nutritional epidemiology is largely based on evidence from studies of observational design, and may be distorted by unmeasured or residual confounding and reverse causation. Mendelian randomization is a recently developed methodology that combines genetic and classical epidemiological analysis to infer causality for environmental exposures, based on the principle of Mendel’s law of independent assortment. Mendelian randomization uses genetic variants as proxiesforenvironmentalexposuresofinterest.AssociationsderivedfromMendelian randomization analysis are less likely to be affected by confounding and reverse causation. During the past 5 years, a body of studies examined the causal effects of diet/lifestyle factors and biomarkers on a variety of diseases. The Mendelian randomization approach also holds considerable promise in the study of intrauterine influences on offspring health outcomes. However, the application of Mendelian randomization in nutritional epidemiology has some limitations. PMID:19674341

Criticality in epidemiology

NASA Astrophysics Data System (ADS)

Stollenwerk, Nico; Jansen, Vincent A. A.

For a long time criticality has been considered in epidemiological models. We review the body of theory developed over the last twenty five years for the simplest models. It is at first glance difficult to imagine that an epidemiological system operates at a very fine tuned critical state as opposed to any other parameter region. However, the advent of self-organized criticality has given hints in how to interpret large fluctuations observed in many natural systems including epidemiological systems. We show some scenarios where criticality has been observed (e.g., measles under vaccination) and where evolution towards a critical state can explain fluctuations (e.g., meningococcal disease.)

Pesticide Exposure and Neurodevelopmental Outcomes: Review of the Epidemiologic and Animal Studies

PubMed Central

Burns, Carol J.; McIntosh, Laura J.; Mink, Pamela J.; Jurek, Anne M.; Li, Abby A.

2013-01-01

Assessment of whether pesticide exposure is associated with neurodevelopmental outcomes in children can best be addressed with a systematic review of both the human and animal peer-reviewed literature. This review analyzed epidemiologic studies testing the hypothesis that exposure to pesticides during pregnancy and/or early childhood is associated with neurodevelopmental outcomes in children. Studies that directly queried pesticide exposure (e.g., via questionnaire or interview) or measured pesticide or metabolite levels in biological specimens from study participants (e.g., blood, urine, etc.) or their immediate environment (e.g., personal air monitoring, home dust samples, etc.) were eligible for inclusion. Consistency, strength of association, and dose response were key elements of the framework utilized for evaluating epidemiologic studies. As a whole, the epidemiologic studies did not strongly implicate any particular pesticide as being causally related to adverse neurodevelopmental outcomes in infants and children. A few associations were unique for a health outcome and specific pesticide, and alternative hypotheses could not be ruled out. Our survey of the in vivo peer-reviewed published mammalian literature focused on effects of the specific active ingredient of pesticides on functional neurodevelopmental endpoints (i.e., behavior, neuropharmacology and neuropathology). In most cases, effects were noted at dose levels within the same order of magnitude or higher compared to the point of departure used for chronic risk assessments in the United States. Thus, although the published animal studies may have characterized potential neurodevelopmental outcomes using endpoints not required by guideline studies, the effects were generally observed at or above effect levels measured in repeated-dose toxicology studies submitted to the U.S. Environmental Protection Agency (EPA). Suggestions for improved exposure assessment in epidemiology studies and more effective

10 CFR 602.5 - Epidemiology and Other Health Studies Financial Assistance Program.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 4 2013-01-01 2013-01-01 false Epidemiology and Other Health Studies Financial Assistance... AND OTHER HEALTH STUDIES FINANCIAL ASSISTANCE PROGRAM § 602.5 Epidemiology and Other Health Studies... toxic substances; (5) Epidemiology and other health studies relating to energy production, transmission...

10 CFR 602.5 - Epidemiology and Other Health Studies Financial Assistance Program.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 4 2014-01-01 2014-01-01 false Epidemiology and Other Health Studies Financial Assistance... AND OTHER HEALTH STUDIES FINANCIAL ASSISTANCE PROGRAM § 602.5 Epidemiology and Other Health Studies... toxic substances; (5) Epidemiology and other health studies relating to energy production, transmission...

10 CFR 602.5 - Epidemiology and Other Health Studies Financial Assistance Program.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 4 2012-01-01 2012-01-01 false Epidemiology and Other Health Studies Financial Assistance... AND OTHER HEALTH STUDIES FINANCIAL ASSISTANCE PROGRAM § 602.5 Epidemiology and Other Health Studies... toxic substances; (5) Epidemiology and other health studies relating to energy production, transmission...

10 CFR 602.5 - Epidemiology and Other Health Studies Financial Assistance Program.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 4 2011-01-01 2011-01-01 false Epidemiology and Other Health Studies Financial Assistance... AND OTHER HEALTH STUDIES FINANCIAL ASSISTANCE PROGRAM § 602.5 Epidemiology and Other Health Studies... toxic substances; (5) Epidemiology and other health studies relating to energy production, transmission...

Carbon Nanotubes Exposure Risk Assessment: From Toxicology to Epidemiologic Studies (Overview of the Current Problem)

PubMed Central

Fatkhutdinova, L. M.; Khaliullin, T. O.; Shvedova, A. A.

2015-01-01

Nanoscale size and fiber like structure of carbon nanotubes (CNTs) may determine high reactivity and penetration, as well as the pathogenicity of asbestos and other mineral fibers. Despite many in vitro and in vivo studies, the absence of full-scale data on CNT effects on human health clearly point out the necessity for epidemiological studies. Currently, several projects are initiated worldwide on studying health risks associated with the inhalation of industrial CNTs, including NIOSH-promoted research (United States), the European CANTES study, and the Russian CNT-ERA project. Studies comprising several successive steps, such as CNT exposure assessment in occupational settings, toxicological evaluation, and epidemiological observations, are critical for determining material safety and use criteria. PMID:26457172

Clavicle fractures: epidemiology, classification and treatment of 2 422 fractures in the Swedish Fracture Register; an observational study.

PubMed

Kihlström, Caroline; Möller, Michael; Lönn, Katarina; Wolf, Olof

2017-02-15

Large multi-centre studies of clavicle fractures have so far been missing. The aim of this observational study was to describe the epidemiology, classification and treatment of clavicle fractures in the The Swedish Fracture Register (SFR) that collects national prospective data from large fracture populations. Data were retrieved from the SFR on all clavicle fractures sustained by patients ≥ 15 years of age in 2013-2014 (n = 2 422) with regards to date of injury, cause of injury, fracture classification and treatment. Sixty-eight per cent of the clavicle fractures occurred in males. The largest subgroup was males aged 15-24 years, representing 21% of clavicle fractures. At the ages of 65 years and above, females sustained more clavicle fractures than males. Same-level falls and bicycle accidents were the most common injury mechanisms. Displaced midshaft fractures constituted 43% of all fractures and were the most frequently operated fractures. Seventeen per cent of the patients underwent operative treatment within 30 days of the injury, where plate fixation was the choice of treatment in 94% of fractures. The largest patient group was young males. Displaced midshaft fractures were the most common type of clavicle fracture as well as the most frequently operated type of fracture.

Epidemiology of moderate-to-severe injury patterns observed in rollover crashes.

PubMed

McMurry, Timothy L; Bose, Dipan; Ridella, Stephen A; Eigen, Ana M; Crandall, Jeff R; Kerrigan, Jason R

2016-05-01

Previous epidemiological studies have highlighted the high risk of injury to the head, thorax, and cervical spine in rollover crashes. However, such results provide limited information on whole-body injury distribution and multiple region injury patterns necessary for the improvement and prioritization of rollover-focused injury countermeasures. Sampled cases representing approximately 133,000 U.S. adult occupants involved in rollover crashes (between 1995 and 2013) sustaining moderate-to-severe injuries were selected from the National Automotive Sampling System Crashworthiness Data System database. A retrospective cohort study, based on a survey of population-based data, was used to identify relevant whole body injury patterns. Among belted occupants injured in rollover crashes, 79.2% sustained injuries to only one body region. The three most frequently injured (AIS2+) body regions were head (42.1%), upper extremity (28.0%), and thorax (27.1%). The most frequent multi-region injury pattern involved the head and upper extremity, but this pattern only accounted for 2.3% of all of occupants with moderate or worse injuries. The results indicated that for rollover-dominated crashes, the frequently observed injury patterns involved isolated body regions. In contrast, multi-region injury patterns are more frequently observed in rollovers with significant planar impacts. Identification of region-specific injury patterns in pure rollover crashes is essential for clarifying injury mitigation targets and developing whole-body injury metrics specifically applicable to rollovers. Copyright © 2016 Elsevier Ltd. All rights reserved.

A review of epidemiological studies on neuropsychological effects of air pollution.

PubMed

Guxens, Mònica; Sunyer, Jordi

2012-01-03

The aim of the present review is to provide an update of the epidemiological evidence of the effects of air pollution on neuropsychological development and impairment, as well as of the evidence on individual susceptibility to these effects. Animal studies have shown deposition of ultrafine particles containing metals in olfactory bulb and frontal cortical and subcortical areas, and overexpression of inflammatory responses, white matter lesions and vascular pathology in these areas that could be the basis for functional and structural brain effects. Several observational studies in the general population have observed cognitive deficits and behavioural impairment in children and the elderly. These effects, however, are not conclusive given the limited number of studies, their small size and their methodological constraints.

The National Heart, Lung, and Blood Institute retrovirus epidemiology donor studies (Retrovirus Epidemiology Donor Study and Retrovirus Epidemiology Donor Study-II): twenty years of research to advance blood product safety and availability.

PubMed

Kleinman, Steven; King, Melissa R; Busch, Michael P; Murphy, Edward L; Glynn, Simone A

2012-10-01

The Retrovirus Epidemiology Donor Study (REDS), conducted from 1989 to 2001, and the REDS-II, conducted from 2004 to 2012, were National Heart, Lung, and Blood Institute-funded, multicenter programs focused on improving blood safety and availability in the United States. The REDS-II also included international study sites in Brazil and China. The 3 major research domains of REDS/REDS-II have been infectious disease risk evaluation, blood donation availability, and blood donor characterization. Both programs have made significant contributions to transfusion medicine research methodology by the use of mathematical modeling, large-scale donor surveys, innovative methods of repository sample storage, and establishing an infrastructure that responded to potential emerging blood safety threats such as xenotropic murine leukemia virus-related virus. Blood safety studies have included protocols evaluating epidemiologic and/or laboratory aspects of human immunodeficiency virus, human T-lymphotropic virus 1/2, hepatitis C virus, hepatitis B virus, West Nile virus, cytomegalovirus, human herpesvirus 8, parvovirus B19, malaria, Creutzfeldt-Jakob disease, influenza, and Trypanosoma cruzi infections. Other analyses have characterized blood donor demographics, motivations to donate, factors influencing donor return, behavioral risk factors, donors' perception of the blood donation screening process, and aspects of donor deferral. In REDS-II, 2 large-scale blood donor protocols examined iron deficiency in donors and the prevalence of leukocyte antibodies. This review describes the major study results from over 150 peer-reviewed articles published by these 2 REDS programs. In 2011, a new 7-year program, the Recipient Epidemiology and Donor Evaluation Study-III, was launched. The Recipient Epidemiology and Donor Evaluation Study-III expands beyond donor-based research to include studies of blood transfusion recipients in the hospital setting and adds a third country, South Africa

Earth observation in support of malaria control and epidemiology: MALAREO monitoring approaches.

PubMed

Franke, Jonas; Gebreslasie, Michael; Bauwens, Ides; Deleu, Julie; Siegert, Florian

2015-06-03

Malaria affects about half of the world's population, with the vast majority of cases occuring in Africa. National malaria control programmes aim to reduce the burden of malaria and its negative, socioeconomic effects by using various control strategies (e.g. vector control, environmental management and case tracking). Vector control is the most effective transmission prevention strategy, while environmental factors are the key parameters affecting transmission. Geographic information systems (GIS), earth observation (EO) and spatial modelling are increasingly being recognised as valuable tools for effective management and malaria vector control. Issues previously inhibiting the use of EO in epidemiology and malaria control such as poor satellite sensor performance, high costs and long turnaround times, have since been resolved through modern technology. The core goal of this study was to develop and implement the capabilities of EO data for national malaria control programmes in South Africa, Swaziland and Mozambique. High- and very high resolution (HR and VHR) land cover and wetland maps were generated for the identification of potential vector habitats and human activities, as well as geoinformation on distance to wetlands for malaria risk modelling, population density maps, habitat foci maps and VHR household maps. These products were further used for modelling malaria incidence and the analysis of environmental factors that favour vector breeding. Geoproducts were also transferred to the staff of national malaria control programmes in seven African countries to demonstrate how EO data and GIS can support vector control strategy planning and monitoring. The transferred EO products support better epidemiological understanding of environmental factors related to malaria transmission, and allow for spatio-temporal targeting of malaria control interventions, thereby improving the cost-effectiveness of interventions.

Soyfood intake in the prevention of breast cancer risk in women: a meta-analysis of observational epidemiological studies.

PubMed

Qin, Li-Qiang; Xu, Jia-Ying; Wang, Pei-Yu; Hoshi, Kazuhiko

2006-12-01

Many studies have suggested that the intake of soy products may protect against the occurrence of breast cancer because of the considerable amount of isoflavones they contain. To review the results of the observational studies, we performed this meta-analysis of the relevant literature. We searched Medline for reports that examined the association between soyfood consumption (or isoflavone intake) and breast cancer risk from January 1966 to April 2006. The random-effects model was used to estimate the pooled relative risk (RR). Twenty-one independent studies (14 case-control studies and 7 cohort studies) were included in the final analysis. The pooled RR of breast cancer for soyfood intake was 0.75 with a 95% CI of 0.59-0.95. As the main types of soyfood in Japan and China, tofu and miso showed clear protective effects. Isoflavone intake resulted in a 20% decrease in risk (RR = 0.81, 95% CI 0.67-0.99). The pooled RR varied little according to study stratification. When the studies published in Japanese and Chinese were added, the inverse associations between soyfood, tofu and breast cancer risk became slightly stronger. The weak association of miso was possibly due to the high concentration of salt in miso soup. In the present analysis, we did not find strong evidence for publication bias in the combination of the studies. This meta-analysis supported the hypotheses that soyfood intake may be associated with a decreased risk of breast cancer due to the isoflavones. Further epidemiological studies need to be conducted with more comprehensive information about the soyfood, and more accurate assessment of the isoflavones.

Colorectal Cancer Epidemiology in the Nurses’ Health Study

PubMed Central

Lee, Dong Hoon; Giovannucci, Edward L.

2016-01-01

Objectives. To review the contribution of the Nurses’ Health Study (NHS) to identifying risk and protective factors for colorectal adenomas and colorectal cancer (CRC). Methods. We performed a narrative review of the publications using the NHS between 1976 and 2016. Results. Existing epidemiological studies using the NHS have reported that red and processed meat, alcohol, smoking, and obesity were associated with an increased risk of CRC, whereas folate, calcium, vitamin D, aspirin, and physical activity were associated with decreased risk of CRC. Moreover, modifiable factors, such as physical activity, vitamin D, folate, insulin and insulin-like growth factor binding protein-1, and diet quality, were identified to be associated with survival among CRC patients. In recent years, molecular pathological epidemiological studies have been actively conducted and have shown refined results by molecular subtypes of CRC. Conclusions. The NHS has provided new insights into colorectal adenomas, CRC etiology, and pathogenic mechanisms. With its unique strengths, the NHS should continue to contribute to the field of CRC epidemiology and play a major role in public health. PMID:27459444

The limitations of opportunistic epidemiology, pseudopod epidemiology.

PubMed

Kuller, Lewis H

2016-10-01

Epidemiology has been remarkably successful in the past in identifying the important agents of disease, the impact of the environment, both physical and social, and interrelationship with host susceptibility (genomics). Many of the advances in improving the health of individuals and populations have been the result of epidemiology studies that have identified the specific "agents" of disease and application of public health and preventive medicine. In recent years, large longitudinal studies have dominated epidemiology research, especially long incubation period chronic diseases. The initial hypotheses in these studies have been expanded by vertical extension studies using newer technologies to measure independent variables, vertical pseudopods, and additional studies of other diseases, horizontal pseudopods, of the original longitudinal study. Host susceptibility, i.e. genomics, has also become a prominent component of these longitudinal studies. The critical question addressed in this paper is whether these "pseudopod" epidemiology approaches have enhanced public health or generated a large number of studies of little impact.

Epidemiological studies of cognitive impairment and dementia across Eastern and Middle European countries (epidemiology of dementia in Eastern and Middle European Countries).

PubMed

Kiejna, A; Frydecka, D; Adamowski, T; Bickel, H; Reynish, E; Prince, M; Caracciolo, B; Fratiglioni, L; Georges, J

2011-02-01

To determine the availability and the consistency of prevalence findings of epidemiological studies on cognitive impairment and dementia conducted in Eastern and Middle Europe. We adopted a stepwise multimethod study approach consisting of iterative literature searches for epidemiological articles published between 1990 and 2006 and subsequent data analyses of published material, reanalyses of existing accessible epidemiological data sets and expert inquiries in Eastern and Middle European countries. Systematic computer-assisted searches used the keywords: "dementia", "Alzheimer", "cognitive impairment", "incidence", "prevalence", "epidemiology" in combination with the name of the relevant countries or "Europe" in English and Polish language. We supplemented the literature search with a review of the references in the articles that were identified during the initial search. We were able to find few regional and country-specific epidemiological studies of various kinds (population-based, cohort, cross-sectional studies) and conducted on different restricted population groups of patients (from neurological units, out-patients units, residential homes). No studies were identified from most of the countries taken under consideration and the ones we found were characterized by an immense diversity with a considerable degree of clinical and methodological variations. The few studies that there are suggest prevalence rates of dementia in Eastern Europe similar to those in Western Europe. There is strong need for epidemiological studies in Eastern and Middle Europe, as well as for greater coordination and standardization of methods to improve the quality and comparability of epidemiological data to determine the prevalences' rates of dementia in all the EU countries. Copyright © 2010 John Wiley & Sons, Ltd.

Risks and Cough-Aggravating Factors in Prolonged Cough. Epidemiological Observations from the Nagahama Cohort Study.

PubMed

Matsumoto, Hisako; Izuhara, Yumi; Niimi, Akio; Tabara, Yasuharu; Nagasaki, Tadao; Kanemitsu, Yoshihiro; Murase, Kimihiko; Oguma, Tsuyoshi; Ito, Isao; Muro, Shigeo; Sekine, Akihiro; Matsuda, Fumihiko; Kosugi, Shinji; Nakayama, Takeo; Chin, Kazuo; Mishima, Michiaki

2017-05-01

Chronic cough hypersensitivity, a potentially important concept of chronic or prolonged cough, is featured by heightened cough response to low-intensity stimuli, which may be generated in the absence of airflow limitations or allergic conditions. However, there is little epidemiological evidence to support this. In this large-scale community survey, we aimed to determine risks and cough-aggravating factors of prolonged cough while focusing on serum IgE levels. Prevalence of prolonged cough, defined as cough lasting 3 weeks or longer, was determined in 9,804 residents from a baseline measurement of the Nagahama Cohort Study, conducted from 2008 to 2010. Risk assessment of prolonged cough was confined to subjects without asthma (n = 9,402). A follow-up measurement of the Nagahama Study was successively conducted from 2013 to 2015, recruiting the same residents living in Nagahama City, Japan (n = 8,292). Validation analysis was performed in the follow-up measurement. In a baseline measurement, prolonged cough was reported by 9.5% of subjects without asthma and 32.3% of subjects with asthma. In subjects without asthma, various cough-aggravating factors were associated with prolonged cough. On the multivariate analysis, several cough-aggravating factors, including nighttime or early morning, weather, pollen season, and common cold, were associated with prolonged cough, independent of female sex, younger age, chronic obstructive pulmonary disease, postnasal drip, daytime sputum, and lower serum total IgE. Serum-specific IgE levels against Japanese cedar pollen were significantly higher in subjects who responded "yes" to "cough in the pollen season" than in those who did not respond, whereas, among subjects who responded "yes" to "cough in the pollen season," prolonged coughers showed lower serum IgE levels against Japanese cedar pollen than temporal coughers. Validation analysis in a follow-up measurement confirmed the associations between prolonged cough and

Cryptic relatedness in epidemiologic collections accessed for genetic association studies: experiences from the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) study and the National Health and Nutrition Examination Surveys (NHANES).

PubMed

Malinowski, Jennifer; Goodloe, Robert; Brown-Gentry, Kristin; Crawford, Dana C

2015-01-01

Epidemiologic collections have been a major resource for genotype-phenotype studies of complex disease given their large sample size, racial/ethnic diversity, and breadth and depth of phenotypes, traits, and exposures. A major disadvantage of these collections is they often survey households and communities without collecting extensive pedigree data. Failure to account for substantial relatedness can lead to inflated estimates and spurious associations. To examine the extent of cryptic relatedness in an epidemiologic collection, we as the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) study accessed the National Health and Nutrition Examination Surveys (NHANES) linked to DNA samples ("Genetic NHANES") from NHANES III and NHANES 1999-2002. NHANES are population-based cross-sectional surveys conducted by the National Center for Health Statistics at the Centers for Disease Control and Prevention. Genome-wide genetic data is not yet available in NHANES, and current data use agreements prohibit the generation of GWAS-level data in NHANES samples due issues in maintaining confidentiality among other ethical concerns. To date, only hundreds of single nucleotide polymorphisms (SNPs) genotyped in a variety of candidate genes are available for analysis in NHANES. We performed identity-by-descent (IBD) estimates in three self-identified subpopulations of Genetic NHANES (non-Hispanic white, non- Hispanic black, and Mexican American) using PLINK software to identify potential familial relationships from presumed unrelated subjects. We then compared the PLINKidentified relationships to those identified by an alternative method implemented in Kinship-based INference for Genome-wide association studies (KING). Overall, both methods identified familial relationships in NHANES III and NHANES 1999-2002 for all three subpopulations, but little concordance was observed between the two methods due in major part to the limited SNP data available in Genetic NHANES

The incidence and prevalence of ankle sprain injury: a systematic review and meta-analysis of prospective epidemiological studies.

PubMed

Doherty, Cailbhe; Delahunt, Eamonn; Caulfield, Brian; Hertel, Jay; Ryan, John; Bleakley, Chris

2014-01-01

Ankle sprain is one of the most common musculoskeletal injuries, yet a contemporary review and meta-analysis of prospective epidemiological studies investigating ankle sprain does not exist. Our aim is to provide an up-to-date account of the incidence rate and prevalence period of ankle sprain injury unlimited by timeframe or context activity. We conducted a systematic review and meta-analyses of English articles using relevant computerised databases. Search terms included Medical Search Headings for the ankle joint, injury and epidemiology. The following inclusion criteria were used: the study must report epidemiology findings of injuries sustained in an observed sample; the study must report ankle sprain injury with either incidence rate or prevalence period among the surveyed sample, or provide sufficient data from which these figures could be calculated; the study design must be prospective. Independent extraction of articles was performed by two authors using pre-determined data fields. One-hundred and eighty-one prospective epidemiology studies from 144 separate papers were included. The average rating of all the included studies was 6.67/11, based on an adapted version of the STROBE (STrengthening the Reporting of OBservational studies in Epidemiology) guidelines for rating observational studies. 116 studies were considered high quality and 65 were considered low quality. The main findings of the meta-analysis demonstrated a higher incidence of ankle sprain in females compared with males (13.6 vs 6.94 per 1,000 exposures), in children compared with adolescents (2.85 vs 1.94 per 1,000 exposures) and adolescents compared with adults (1.94 vs 0.72 per 1,000 exposures). The sport category with the highest incidence of ankle sprain was indoor/court sports, with a cumulative incidence rate of 7 per 1,000 exposures or 1.37 per 1,000 athlete exposures and 4.9 per 1,000 h. Low-quality studies tended to underestimate the incidence of ankle sprain when compared with

Chapter 8. Tea and Cancer Prevention: Epidemiological Studies

PubMed Central

Yuan, Jian-Min; Sun, Canlan; Butler, Lesley M.

2011-01-01

Experimental studies have consistently shown the inhibitory activities of tea extracts on tumorigenesis in multiple model systems. Epidemiologic studies, however, have produced inconclusive results in humans. A comprehensive review was conducted to assess the current knowledge on tea consumption and risk of cancers in humans. In general, consumption of black tea was not associated with lower risk of cancer. High intake of green tea was consistently associated with reduced risk of upper gastrointestinal tract cancers after sufficient control for confounders. Limited data support a protective effect of green tea on lung and hepatocellular carcinogenesis. Although observational studies do not support a beneficial role of tea intake on prostate cancer risk, phase II clinical trials have demonstrated an inhibitory effect of green tea extract against the progression of prostate pre-malignant lesions. Green tea may exert beneficial effects against mammary carcinogenesis in premenopausal women and recurrence of breast cancer. There is no sufficient evidence that supports a protective role of tea intake on the development of cancers of the colorectum, pancreas, urinary tract, glioma, lymphoma, and leukemia. Future prospective observational studies with biomarkers of exposure and phase III clinical trials are required to provide definitive evidence for the hypothesized beneficial effect of tea consumption on cancer formation in humans. PMID:21419224

An assessment of the possible extent of confounding in epidemiological studies of lung cancer risk among roofers

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

Mundt, D.J.; van Wijngaarden, E.; Mundt, K.A.

2007-07-01

We evaluated the likelihood and extent to which the observed increased risk of lung cancer may be due to confounding (a mixing of effects of multiple exposures) by co-exposure to other potential carcinogens present in roofing or to lifestyle variables. We conducted a review of the epidemiological and industrial hygiene literature of asphalt-exposed workers. Peer-reviewed epidemiological studies of asphalt fumes, related occupational exposures, and confounding factors were identified from MEDLINE (1966 early 2004). Industrial hygiene studies of asphalt workers were identified through MEDLINE, publicly available government documents, and asphalt industry documents. Using well established statistical methods, we quantified the extentmore » to which lung cancer relative risk estimates among roofers reflect confounding from other exposures, using different prevalence and risk scenarios. The relative risk of lung cancer varied from 1.2 to 5.0 in 13 epidemiological studies of roofers; most studies reported a relative risk between 1.2 and 1.4. Smoking, asbestos and coal tar were the most likely confounders, but the prevalence of these factors varied over time. The results of the study indicate that much of the observed risk reported in epidemiological studies of cancer among roofers is well within the range of what may have resulted from confounding by reasonable and expected levels of smoking, asbestos or coal tar. This may be particularly true for those studies that did not adjust for these confounders and where the exposure was defined as employment in the roofing industry. In addition to poorly defined asphalt exposure, uncontrolled confounding cannot reliably be ruled out in studies of lung cancer among asphalt-exposed roofers. Therefore, it is not possible to conclude whether roofers are at increased risk of lung cancer due to asphalt exposure.« less

Using Geographic Information Systems for Exposure Assessment in Environmental Epidemiology Studies

PubMed Central

Nuckols, John R.; Ward, Mary H.; Jarup, Lars

2004-01-01

Geographic information systems (GIS) are being used with increasing frequency in environmental epidemiology studies. Reported applications include locating the study population by geocoding addresses (assigning mapping coordinates), using proximity analysis of contaminant source as a surrogate for exposure, and integrating environmental monitoring data into the analysis of the health outcomes. Although most of these studies have been ecologic in design, some have used GIS in estimating environmental levels of a contaminant at the individual level and to design exposure metrics for use in epidemiologic studies. In this article we discuss fundamentals of three scientific disciplines instrumental to using GIS in exposure assessment for epidemiologic studies: geospatial science, environmental science, and epidemiology. We also explore how a GIS can be used to accomplish several steps in the exposure assessment process. These steps include defining the study population, identifying source and potential routes of exposure, estimating environmental levels of target contaminants, and estimating personal exposures. We present and discuss examples for the first three steps. We discuss potential use of GIS and global positioning systems (GPS) in the last step. On the basis of our findings, we conclude that the use of GIS in exposure assessment for environmental epidemiology studies is not only feasible but can enhance the understanding of the association between contaminants in our environment and disease. PMID:15198921

Molecular epidemiological study of HIV-1 CRF01_AE transmission in Hong Kong.

PubMed

Chen, J H K; Wong, K H; Li, P; Chan, K C; Lee, M P; Lam, H Y; Cheng, V C C; Yuen, K Y; Yam, W C

2009-08-15

The objective of this study was to investigate the transmission history of the HIV-1 CRF01_AE epidemics in Hong Kong between 1994 and 2007. A total of 465 HIV-1 CRF01_AE pol sequences were derived from an in-house or a commercial HIV-1 genotyping system. Phylogenies of CRF01_AE sequences were analyzed by the Bayesian coalescent method. CRF01_AE patient population included 363 males (78.1%) and 102 females (21.9%), whereas 65% (314 of 465) were local Chinese. Major transmission routes were heterosexual contact (63%), followed by intravenous drug use (IDU) (19%) and men having sex with men (MSM) (17%). From phylogenetic analysis, local CRF01_AE strains were from multiple origins with 3 separate transmission clusters identified. Cluster 1 consisted mainly of Chinese male IDUs and heterosexuals. Clusters 2 and 3 included mainly local Chinese MSM and non-Chinese Asian IDUs, respectively. Chinese reference isolates available from China (Fujian, Guangxi, or Liaoning) were clonally related to our transmission clusters, demonstrating the epidemiological linkage of CRF01_AE infections between Hong Kong and China. The 3 individual local transmission clusters were estimated to have initiated since late 1980s and late 1990s, causing subsequent epidemics in the early 2000s. This is the first comprehensive molecular epidemiological study of HIV-1 CRF01_AE in Hong Kong. It revealed that MSM contact is becoming a major route of local CRF01_AE transmission in Hong Kong. Epidemiological linkage of CRF01_AE between Hong Kong and China observed in this study indicates the importance of regular molecular epidemiological surveillance for the HIV-1 epidemic in our region.

Guidelines for Good Epidemiology Practices for Occupational and Environmental Epidemiologic Research. The Chemical Manufacturers Association's Epidemiology Task Group.

PubMed

1991-12-01

The Guidelines for Good Epidemiology Practices (GEPs) for Occupational and Environmental Epidemiologic Research address the conduct of studies generally undertaken to answer questions about human health in relationship to the work place or the environment. The GEPs propose minimum practices and procedures that should be considered to help ensure the quality and integrity of data used in epidemiologic research and to provide adequate documentation of the research methods. The GEPs address the process of conducting individual epidemiologic studies and do not prescribe specific research methods. The Guidelines for Good Epidemiology Practices propose minimum practices and procedures in the following areas: I. Organization and Personnel II. Facilities, Resource Commitment, and Contractors III. Protocol IV. Review and Approval V. Study Conduct VI. Communication VII. Archiving VIII. Quality Assurance Although the Guidelines for Good Epidemiology Practices will not guarantee good epidemiology, they do provide a useful framework for ensuring that all research issues are adequately addressed. This framework is proposed as a first step in improving epidemiologic research practices through adherence to sound scientific research principles. Appendices provide an overview of standard operating procedures, a glossary of terms used in the Guidelines, and suggested references on occupational epidemiology methods.

IDGenerator: unique identifier generator for epidemiologic or clinical studies.

PubMed

Olden, Matthias; Holle, Rolf; Heid, Iris M; Stark, Klaus

2016-09-15

Creating study identifiers and assigning them to study participants is an important feature in epidemiologic studies, ensuring the consistency and privacy of the study data. The numbering system for identifiers needs to be random within certain number constraints, to carry extensions coding for organizational information, or to contain multiple layers of numbers per participant to diversify data access. Available software can generate globally-unique identifiers, but identifier-creating tools meeting the special needs of epidemiological studies are lacking. We have thus set out to develop a software program to generate IDs for epidemiological or clinical studies. Our software IDGenerator creates unique identifiers that not only carry a random identifier for a study participant, but also support the creation of structured IDs, where organizational information is coded into the ID directly. This may include study center (for multicenter-studies), study track (for studies with diversified study programs), or study visit (baseline, follow-up, regularly repeated visits). Our software can be used to add a check digit to the ID to minimize data entry errors. It facilitates the generation of IDs in batches and the creation of layered IDs (personal data ID, study data ID, temporary ID, external data ID) to ensure a high standard of data privacy. The software is supported by a user-friendly graphic interface that enables the generation of IDs in both standard text and barcode 128B format. Our software IDGenerator can create identifiers meeting the specific needs for epidemiologic or clinical studies to facilitate study organization and data privacy. IDGenerator is freeware under the GNU General Public License version 3; a Windows port and the source code can be downloaded at the Open Science Framework website: https://osf.io/urs2g/ .

[Bibliometric analysis of scientific articles on epidemiological study of burns in China].

PubMed

Cheng, W F; Shen, Z A; Zhao, D X; Li, D W; Shang, Y R

2017-04-20

Objective: To analyze the current status of epidemiological study of burns in China, and to explore the related strategies. Methods: Retrospective or cross-sectional scientific articles in Chinese or English on epidemiological study of burns in China published from January 2005 to December 2015 were systemically retrieved from 4 databases. The databases include PubMed, Embase, China Biology Medicine disc, and Chinese Journals Full - text Database . From the results retrieved, data with regard to publication year, journal distribution, number of institutions participated in the study, affiliation of the first author and its location, and admission time span and age of patients in all the scientific articles were collected. Furthermore, the definition of age range and the grouping method of age of pediatric patients in English articles on epidemiological study of pediatric burns of China were recorded. Data were processed with descriptive statistical analysis. Results: A total of 256 scientific articles conforming to the study criteria were retrieved, among which 214 (83.59%) articles were in Chinese, and 42 (16.41%) articles were in English; 242 (94.53%) articles were retrospective studies, and 14 (5.47%) articles were cross-sectional studies. During the 11 years, the number of the relevant articles was fluctuant on the whole. The scientific articles were published in 130 journals, with 42 English articles in source journals for SCIENCE CITATION INDEX EXPANDED - JOURNAL LIST, accounting for 16.41%, and 116 Chinese articles in Source Journal for Chinese Scientific and Technical Papers, accounting for 45.31%. Totally 215 (83.98%) articles were single-center studies, and 29 (11.33%) articles were multicenter studies which were conducted by three or more centers. The number of affiliations of the first author of articles was 161 in total. The top 10 institutions regarding the article publishing number published 58 articles, accounting for 22.66%. Scientific articles on

Satellite remote sensing in epidemiological studies.

PubMed

Sorek-Hamer, Meytar; Just, Allan C; Kloog, Itai

2016-04-01

Particulate matter air pollution is a ubiquitous exposure linked with multiple adverse health outcomes for children and across the life course. The recent development of satellite-based remote-sensing models for air pollution enables the quantification of these risks and addresses many limitations of previous air pollution research strategies. We review the recent literature on the applications of satellite remote sensing in air quality research, with a focus on their use in epidemiological studies. Aerosol optical depth (AOD) is a focus of this review and a significant number of studies show that ground-level particulate matter can be estimated from columnar AOD. Satellite measurements have been found to be an important source of data for particulate matter model-based exposure estimates, and recently have been used in health studies to increase the spatial breadth and temporal resolution of these estimates. It is suggested that satellite-based models improve our understanding of the spatial characteristics of air quality. Although the adoption of satellite-based measures of air quality in health studies is in its infancy, it is rapidly growing. Nevertheless, further investigation is still needed in order to have a better understanding of the AOD contribution to these prediction models in order to use them with higher accuracy in epidemiological studies.

Landmarks in the history of cancer epidemiology.

PubMed

Greenwald, Peter; Dunn, Barbara K

2009-03-15

The application of epidemiology to cancer prevention is relatively new, although observations of the potential causes of cancer have been reported for more than 2,000 years. Cancer was generally considered incurable until the late 19th century. Only with a refined understanding of the nature of cancer and strategies for cancer treatment could a systematic approach to cancer prevention emerge. The 20th century saw the elucidation of clues to cancer causation from observed associations with population exposures to tobacco, diet, environmental chemicals, and other exogenous factors. With repeated confirmation of such associations, researchers entertained for the first time the possibility that cancer, like many of the infectious diseases of the time, might be prevented. By the mid-20th century, with antibiotics successfully addressing the majority of infectious diseases and high blood pressure treatment beginning to affect the prevalence of heart disease in a favorable direction, the focus of much of epidemiology shifted to cancer. The early emphasis was on exploring, in greater depth, the environmental, dietary, hormonal, and other exogenous exposures for their potential associations with increased cancer risk. The first major breakthrough in identifying a modifiable cancer risk factor was the documentation of an association between tobacco smoking and lung cancer. During the past four decades, epidemiologic studies have generated population data identifying risk factors for cancers at almost every body site, with many cancers having multiple risk factors. The development of technologies to identify biological molecules has facilitated the incorporation of these molecular manifestations of biological variation into epidemiologic studies, as markers of exposure as well as putative surrogate markers of cancer outcome. This technological trend has, during the past two decades, culminated in emphasis on the identification of genetic variants and their products as

Epidemiological risk factors in microscopic colitis: a prospective case-control study.

PubMed

Fernández-Bañares, Fernando; de Sousa, Monia R; Salas, Antonio; Beltrán, Belén; Piqueras, Marta; Iglesias, Eva; Gisbert, Javier P; Lobo, Beatriz; Puig-Diví, Valentí; García-Planella, Esther; Ordás, Ingrid; Andreu, Montserrat; Calvo, Marta; Montoro, Miguel; Esteve, Maria; Viver, Josep M

2013-02-01

The cause of collagenous colitis (CC) and lymphocytic colitis (LC) is unknown and epidemiological risk factors for CC and LC are not well studied. The aim was to evaluate in a case-control study epidemiological risk factors for CC and LC. In all, 120 patients with CC, 70 with CL, and 128 controls were included. For all cases and controls information was prospectively recorded. A binary logistic regression analysis was performed separately for CC and LC. Independent associations observed with the diagnosis of CC were: current smoking (odds ratio [OR], 2.4), history of polyarthritis (OR, 20.8), and consumption of lansoprazole (OR, 6.4), low-dose aspirin (OR, 3.8), beta-blockers (OR, 3.6), and angiotensin II receptor antagonists (OR 0.20). In the case of LC they were: current smoking (OR, 3.8), associated autoimmune diseases (OR, 8), and consumption of sertraline (OR, 17.5), omeprazole (OR 2.7), low-dose aspirin (OR, 4.7), and oral antidiabetic drugs (OR, 0.14). The consumption of drugs, current smoking, and associated autoimmune diseases were independently associated with the risk of microscopic colitis.

Epidemiology of Guillain–Barré Syndrome in Aruba

PubMed Central

Suryapranata, Franciska S. T.; Ang, C. Wim; Chong, Luis L.; Murk, Jean-Luc; Falconi, Jaime; Huits, Ralph M. H. G.

2016-01-01

The epidemiology of Guillain–Barré syndrome (GBS) in tropical areas is different compared with developed countries. We investigated the epidemiology of GBS on the Caribbean island of Aruba. Data were collected retrospectively from all 36 patients hospitalized with GBS between 2003 and 2011 in Aruba. We observed a seasonal distribution of GBS cases with a peak in February. The incidence rate (IR) fluctuated heavily between individual years. The overall IR was 3.93/100,000, which is higher than that observed in developed countries. Serological studies indicated a possible relation of GBS cases with dengue virus infections. We also observed a relation between the annual number of dengue cases in Aruba and the number of GBS cases in the same year. We conclude that the epidemiology of GBS in tropical areas can be different from temperate climate regions and that dengue may be a trigger for developing GBS. PMID:27022152

Cancer prevention by green tea: evidence from epidemiologic studies.

PubMed

Yuan, Jian-Min

2013-12-01

In contrast to the consistent results of an inhibitory effect of green tea extracts and tea polyphenols on the development and growth of carcinogen-induced tumors in experimental animal models, results from human studies are mixed. Both observational and intervention studies have provided evidence in support of a protective role of green tea intake in the development of oral-digestive tract cancer or an inhibitory role of oral supplementation of green tea extract on a precancerous lesion of oral cavity. Evidence in support of green tea intake against the development of liver cancer risk is limited and inconsistent. An inverse association between green tea intake and lung cancer risk has been observed among never smokers but not among smokers. Although observational studies do not support a beneficial role of tea intake against the development of prostate cancer, several phase 2 clinical trials have shown an inhibitory effect of green tea extract against the progression of prostate premalignant lesions to malignant tumors. Prospective epidemiologic studies so far have not provided evidence for a protective effect of green tea consumption on breast cancer development. Current data neither confirm nor refute a definitive cancer-preventive role of green tea intake. Large randomized intervention trials on the efficacy of green tea polyphenols or extracts are required before a recommendation for green tea consumption for cancer prevention should be made.

[Molecular epidemiology in the epidemiological transition].

PubMed

Tapia-Conyer, R

1997-01-01

The epidemiological transition describes the changes in the health profile of populations where infectious diseases are substituted by chronic or non-communicable diseases. Even in industrialized countries, infectious diseases emerge as important public health problems and with a very important association with several type of neoplasm. Molecular epidemiology brings in new tools for the study of the epidemiological transition by discovering infectious agents as etiology of diseases, neither of both new. Much has been advanced in the understanding of the virulence and resistance mechanism of different strains, or improving the knowledge on transmission dynamics and dissemination pathways of infectious diseases. As to the non-communicable diseases, molecular epidemiology has enhanced the identification of endogenous risk factors link to alterations, molecular changes in genetic material, that will allow a more detail definition of risk and the identification of individual and groups at risk of several diseases. The potential impact of molecular epidemiology in other areas as environmental, lifestyles and nutritional areas are illustrated with several examples.

Overview of Recent Marine and Freshwater Recreational Epidemiology Studies and Their Findings

EPA Science Inventory

Overview of Recent Marine and Freshwater Recreational Epidemiology Studies and Their Findings Timothy J. Wade, Elizabeth A. Sams, Rich Haugland, Alfred P. Dufour The National Epidemiologic and Environmental Assessment of Recreational Water Study was conducted to address aspects...

Epidemiological Studies to Support the Development of Next Generation Influenza Vaccines.

PubMed

Petrie, Joshua G; Gordon, Aubree

2018-03-26

The National Institute of Allergy and Infectious Diseases recently published a strategic plan for the development of a universal influenza vaccine. This plan focuses on improving understanding of influenza infection, the development of influenza immunity, and rational design of new vaccines. Epidemiological studies such as prospective, longitudinal cohort studies are essential to the completion of these objectives. In this review, we discuss the contributions of epidemiological studies to our current knowledge of vaccines and correlates of immunity, and how they can contribute to the development and evaluation of the next generation of influenza vaccines. These studies have been critical in monitoring the effectiveness of current influenza vaccines, identifying issues such as low vaccine effectiveness, reduced effectiveness among those who receive repeated vaccination, and issues related to egg adaptation during the manufacturing process. Epidemiological studies have also identified population-level correlates of protection that can inform the design and development of next generation influenza vaccines. Going forward, there is an enduring need for epidemiological studies to continue advancing knowledge of correlates of protection and the development of immunity, to evaluate and monitor the effectiveness of next generation influenza vaccines, and to inform recommendations for their use.

Cancer Epidemiology Data Repository (CEDR)

Cancer.gov

In an effort to broaden access and facilitate efficient data sharing, the Epidemiology and Genomics Research Program (EGRP) has created the Cancer Epidemiology Data Repository (CEDR), a centralized, controlled-access database, where Investigators can deposit individual-level de-identified observational cancer datasets.

Sequencing Strategies for Population and Cancer Epidemiology Studies (SeqSPACE) Webinar Series

Cancer.gov

The Sequencing Strategies for Population and Cancer Epidemiology Studies (SeqSPACE) Webinar Series provides an opportunity for our grantees and other interested individuals to share lessons learned and practical information regarding the application of next generation sequencing to cancer epidemiology studies.

Epidemiological Study of Greek University Students' Mental Health

ERIC Educational Resources Information Center

Kounenou, Kalliope; Koutra, Aikaterini; Katsiadrami, Aristea; Diacogiannis, Georgios

2011-01-01

In the present study, 805 Greek students participated by filling in self-report questionnaires studying depression (Center for Epidemiological Studies Depression Scale), general health status (General Health Questionnaire), general psychopathology (Symptom Checklist-90-R), and personal demographic features. Some of the more prevalent findings…

Translational Epidemiology in Psychiatry

PubMed Central

Weissman, Myrna M.; Brown, Alan S.; Talati, Ardesheer

2012-01-01

Translational research generally refers to the application of knowledge generated by advances in basic sciences research translated into new approaches for diagnosis, prevention, and treatment of disease. This direction is called bench-to-bedside. Psychiatry has similarly emphasized the basic sciences as the starting point of translational research. This article introduces the term translational epidemiology for psychiatry research as a bidirectional concept in which the knowledge generated from the bedside or the population can also be translated to the benches of laboratory science. Epidemiologic studies are primarily observational but can generate representative samples, novel designs, and hypotheses that can be translated into more tractable experimental approaches in the clinical and basic sciences. This bedside-to-bench concept has not been explicated in psychiatry, although there are an increasing number of examples in the research literature. This article describes selected epidemiologic designs, providing examples and opportunities for translational research from community surveys and prospective, birth cohort, and family-based designs. Rapid developments in informatics, emphases on large sample collection for genetic and biomarker studies, and interest in personalized medicine—which requires information on relative and absolute risk factors—make this topic timely. The approach described has implications for providing fresh metaphors to communicate complex issues in interdisciplinary collaborations and for training in epidemiology and other sciences in psychiatry. PMID:21646577

Measuring taste impairment in epidemiologic studies: the Beaver Dam Offspring Study.

PubMed

Cruickshanks, K J; Schubert, C R; Snyder, D J; Bartoshuk, L M; Huang, G H; Klein, B E K; Klein, R; Nieto, F J; Pankow, J S; Tweed, T S; Krantz, E M; Moy, G S

2009-07-01

Taste or gustatory function may play an important role in determining diet and nutritional status and therefore indirectly impact health. Yet there have been few attempts to study the spectrum of taste function and dysfunction in human populations. Epidemiologic studies are needed to understand the impact of taste function and dysfunction on public health, to identify modifiable risk factors, and to develop and test strategies to prevent clinically significant dysfunction. However, measuring taste function in epidemiologic studies is challenging and requires repeatable, efficient methods that can measure change over time. Insights gained from translating laboratory-based methods to a population-based study, the Beaver Dam Offspring Study (BOSS) will be shared. In this study, a generalized labeled magnitude scale (gLMS) method was used to measure taste intensity of filter paper disks saturated with salt, sucrose, citric acid, quinine, or 6-n-propylthiouracil, and a gLMS measure of taste preferences was administered. In addition, a portable, inexpensive camera system to capture digital images of fungiform papillae and a masked grading system to measure the density of fungiform papillae were developed. Adult children of participants in the population-based Epidemiology of Hearing Loss Study in Beaver Dam, Wisconsin, are eligible for this ongoing study. The parents were residents of Beaver Dam and 43-84 years of age in 1987-1988; offspring ranged in age from 21-84 years in 2005-2008. Methods will be described in detail and preliminary results about the distributions of taste function in the BOSS cohort will be presented.

Local health department epidemiologic capacity: a stratified cross-sectional assessment describing the quantity, education, training, and perceived competencies of epidemiologic staff.

PubMed

O'Keefe, Kaitlin A; Shafir, Shira C; Shoaf, Kimberley I

2013-01-01

Local health departments (LHDs) must have sufficient numbers of staff functioning in an epidemiologic role with proper education, training, and skills to protect the health of communities they serve. This pilot study was designed to describe the composition, training, and competency level of LHD staff and examine the hypothesis that potential disparities exist between LHDs serving different sized populations. Cross-sectional surveys were conducted with directors and epidemiologic staff from a sample of 100 LHDs serving jurisdictions of varied sizes. Questionnaires included inquiries regarding staff composition, education, training, and measures of competency modeled on previously conducted studies by the Council of State and Territorial Epidemiologists. Number of epidemiologic staff, academic degree distribution, epidemiologic training, and both director and staff confidence in task competencies were calculated for each LHD size strata. Disparities in measurements were observed in LHDs serving different sized populations. LHDs serving small populations reported a smaller average number of epidemiologic staff than those serving larger jurisdictions. As size of population served increased, percentages of staff and directors holding bachelors' and masters' degrees increased, while those holding RN degrees decreased. A higher degree of perceived competency of staff in most task categories was reported in LHDs serving larger populations. LHDs serving smaller populations reported fewer epidemiologic staff, therefore might benefit from additional resources. Differences observed in staff education, training, and competencies suggest that enhanced epidemiologic training might be particularly needed in LHDs serving smaller populations. RESULTS can be used as a baseline for future research aimed at identifying areas where training and personnel resources might be particularly needed to increase the capabilities of LHDs.

Epidemiology of Chikungunya Virus Outbreaks in Guadeloupe and Martinique, 2014: An Observational Study in Volunteer Blood Donors.

PubMed

Gallian, Pierre; Leparc-Goffart, Isabelle; Richard, Pascale; Maire, Françoise; Flusin, Olivier; Djoudi, Rachid; Chiaroni, Jacques; Charrel, Remi; Tiberghien, Pierre; de Lamballerie, Xavier

2017-01-01

During Dec-2013, a chikungunya virus (CHIKV) outbreak was first detected in the French-West Indies. Subsequently, the virus dispersed to other Caribbean islands, continental America and many islands in the Pacific Ocean. Previous estimates of the attack rate were based on declaration of clinically suspected cases. Individual testing for CHIKV RNA of all (n = 16,386) blood donations between Feb-24th 2014 and Jan-31st 2015 identified 0·36% and 0·42% of positives in Guadeloupe and Martinique, respectively. The incidence curves faithfully correlated with those of suspected clinical cases in the general population of Guadeloupe (abrupt epidemic peak), but not in Martinique (flatter epidemic growth). No significant relationship was identified between CHIKV RNA detection and age-classes or blood groups. Prospective (Feb-2014 to Jan-2015; n = 9,506) and retrospective (Aug-2013 to Feb-2014; n = 6,559) seroepidemiological surveys in blood donors identified a final seroprevalence of 48·1% in Guadeloupe and 41·9% in Martinique. Retrospective survey also suggested the absence or limited "silent" CHIKV circulation before the outbreak. Parameters associated with increased seroprevalence were: Gender (M>F), KEL-1, [RH+1/KEL-1], [A/RH+1] and [A/RH+1/KEL-1] blood groups in Martiniquan donors. A simulation model based on observed incidence and actual seroprevalence values predicted 2·5 and 2·3 days of asymptomatic viraemia in Martiniquan and Guadeloupian blood donors respectively. This study, implemented promptly with relatively limited logistical requirements during CHIKV emergence in the Caribbean, provided unique information regarding retrospective and prospective epidemiology, infection risk factors and natural history of the disease. In the stressful context of emerging infectious disease outbreaks, blood donor-based studies can serve as robust and cost-effective first-line tools for public health surveys.

Implementation and reporting of causal mediation analysis in 2015: a systematic review in epidemiological studies.

PubMed

Liu, Shao-Hsien; Ulbricht, Christine M; Chrysanthopoulou, Stavroula A; Lapane, Kate L

2016-07-20

Causal mediation analysis is often used to understand the impact of variables along the causal pathway of an occurrence relation. How well studies apply and report the elements of causal mediation analysis remains unknown. We systematically reviewed epidemiological studies published in 2015 that employed causal mediation analysis to estimate direct and indirect effects of observed associations between an exposure on an outcome. We identified potential epidemiological studies through conducting a citation search within Web of Science and a keyword search within PubMed. Two reviewers independently screened studies for eligibility. For eligible studies, one reviewer performed data extraction, and a senior epidemiologist confirmed the extracted information. Empirical application and methodological details of the technique were extracted and summarized. Thirteen studies were eligible for data extraction. While the majority of studies reported and identified the effects of measures, most studies lacked sufficient details on the extent to which identifiability assumptions were satisfied. Although most studies addressed issues of unmeasured confounders either from empirical approaches or sensitivity analyses, the majority did not examine the potential bias arising from the measurement error of the mediator. Some studies allowed for exposure-mediator interaction and only a few presented results from models both with and without interactions. Power calculations were scarce. Reporting of causal mediation analysis is varied and suboptimal. Given that the application of causal mediation analysis will likely continue to increase, developing standards of reporting of causal mediation analysis in epidemiological research would be prudent.

The reporting of observational research studies in dermatology journals: a literature-based study.

PubMed

Langan, Sinéad; Schmitt, Jochen; Coenraads, Pieter-Jan; Svensson, Ake; von Elm, Erik; Williams, Hywel

2010-05-01

To assess the quality of reporting in observational studies in dermatology. Five dermatology journals-the Archives of Dermatology, the British Journal of Dermatology, the Journal of the American Academy of Dermatology, the Journal of Investigative Dermatology, and Acta Dermato-Venereologica. Cohort, case-control, and cross-sectional studies published as original articles during the period January 2005 through December 2007. Studies were identified with a literature search of PubMed combining the journal title and the term epidemiological studies (free text) and by hand searching all of the issues of each journal to identify relevant articles. All articles were extracted by 2 reviewers independently using standardized checklists based on the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) recommendations. The number and proportion of reported STROBE items were analyzed for each article. The proportion of studies with good reporting for each item was also assessed. A total of 138 articles were included and analyzed. Reporting quality was very mixed. Key areas that were infrequently reported included sample size calculations (n = 10 [7%]), missing data (n = 8 [6%]), losses to follow-up (n = 17 [12%]), and statistical methods (n = 19 [14%]). Only 13 studies (9%) explained the role of funders in the research. The quality of reporting was similar across study designs for "critical" questions with the exception of reporting of participant details, which was better reported in cohort studies (96%) compared with cross-sectional (80%) and case-control (70%) studies. It is difficult to judge the quality of dermatological research unless it is reported well. This study has identified a clear need to improve the quality of reporting of observational studies in dermatology. We recommend that dermatology journals adopt the STROBE criteria.

Multiple sclerosis epidemiology in Latin America: An updated survey

PubMed Central

Rojas, Juan Ignacio

2017-01-01

Novel epidemiological data have appeared in recent years in Latin America (LATAM). The objective of this study was to perform an updated systematic review of the epidemiology of the disease reported in LATAM. Methods We conducted a systematic review of published epidemiological articles from January 1995 to December 2016. Results Incidence data were found in four studies and ranged from 0.3 to 3 annual cases per 100,000 person-years. Prevalence was reported in 13 studies and ranged from 0.83 to 38.2 cases per 100,000 inhabitants. Two studies showed an increase in prevalence and incidence in the last five years in specific regions. Conclusion The study provides updated information on epidemiological features of MS in the region. The frequency reported is lower compared with some European and North American countries; however, due to recent observations, studies including follow-up assessment of prevalence and incidence should be conducted in the region. PMID:28638628

[Uranium exposure and cancer risk: a review of epidemiological studies].

PubMed

Tirmarche, M; Baysson, H; Telle-Lamberton, M

2004-02-01

At the end of 2000, certain diseases including leukemia were reported among soldiers who participated in the Balkan and in the Gulf wars. Depleted uranium used during these conflicts was considered as a possible cause. Its radiotoxicity is close to that of natural uranium. This paper reviews the epidemiological knowledge of uranium, the means of exposure and the associated risk of cancer. The only available epidemiological data concerns nuclear workers exposed to uranium. A review of the international literature is proposed by distinguishing between uranium miners and other workers of the nuclear industry. French studies are described in details. In ionizing radiation epidemiology, contamination by uranium is often cited as a risk factor, but the dose-effect relationship is rarely studied. Retrospective assessment of individual exposure is generally insufficient. Moreover, it is difficult to distinguish between uranium radiotoxicity, its chemical toxicity and the radiotoxicity of its progeny. A causal relation between lung cancer and radon exposure, a gas derived from the decay of uranium, has been demonstrated in epidemiological studies of miners. Among other nuclear workers exposed to uranium, there is a mortality deficit from all causes (healthy worker effect). No cancer site appears systematically in excess compared to the national population; very few studies describe a dose-response relationship. Only studies with a precise reconstruction of doses and sufficient numbers of workers will allow a better assessment of risks associated with uranium exposure at levels encountered in industry or during conflicts using depleted uranium weapons.

Comparing toxicologic and epidemiologic studies: methylene chloride--a case study.

PubMed

Stayner, L T; Bailer, A J

1993-12-01

Exposure to methylene chloride induces lung and liver cancers in mice. The mouse bioassay data have been used as the basis for several cancer risk assessments. The results from epidemiologic studies of workers exposed to methylene chloride have been mixed with respect to demonstrating an increased cancer risk. The results from a negative epidemiologic study of Kodak workers have been used by two groups of investigators to test the predictions from the EPA risk assessment models. These two groups used very different approaches to this problem, which resulted in opposite conclusions regarding the consistency between the animal model predictions and the Kodak study results. The results from the Kodak study are used to test the predictions from OSHA's multistage models of liver and lung cancer risk. Confidence intervals for the standardized mortality ratios (SMRs) from the Kodak study are compared with the predicted confidence intervals derived from OSHA's risk assessment models. Adjustments for the "healthy worker effect," differences in length of follow-up, and dosimetry between animals and humans were incorporated into these comparisons. Based on these comparisons, we conclude that the negative results from the Kodak study are not inconsistent with the predictions from OSHA's risk assessment model.

Doses for post-Chernobyl epidemiological studies: are they reliable?

PubMed

Drozdovitch, Vladimir; Chumak, Vadim; Kesminiene, Ausrele; Ostroumova, Evgenia; Bouville, André

2016-09-01

On 26 April 2016, thirty years will have elapsed since the occurrence of the Chernobyl accident, which has so far been the most severe in the history of the nuclear reactor industry. Numerous epidemiological studies were conducted to evaluate the possible health consequences of the accident. Since the credibility of the association between the radiation exposure and health outcome is highly dependent on the adequacy of the dosimetric quantities used in these studies, this paper makes an effort to overview the methods used to estimate individual doses and the associated uncertainties in the main analytical epidemiological studies (i.e. cohort or case-control) related to the Chernobyl accident. Based on the thorough analysis and comparison with other radiation studies, the authors conclude that individual doses for the Chernobyl analytical epidemiological studies have been calculated with a relatively high degree of reliability and well-characterized uncertainties, and that they compare favorably with many other non-Chernobyl studies. The major strengths of the Chernobyl studies are: (1) they are grounded on a large number of measurements, either performed on humans or made in the environment; and (2) extensive effort has been invested to evaluate the uncertainties associated with the dose estimates. Nevertheless, gaps in the methodology are identified and suggestions for the possible improvement of the current dose estimates are made.

Current methods for molecular epidemiology studies of implant infections.

PubMed

Campoccia, Davide; Montanaro, Lucio; Arciola, Carla Renata

2009-09-01

Over the last few decades, the number of surgical procedures involving prosthetic materials has greatly multiplied, along with the rising medical and economic impact of implant-associated infections. The need to appropriately counteract and deal with this phenomenon has led to growing efforts to elucidate the etiology, pathogenesis and epidemiology of these types of infections, characterized by opportunistic pathogens. Molecular epidemiology studies have progressively emerged as a leading multitask tool to identify and fingerprint bacterial strains, unveil the complex clonal nature of important pathogens, detect outbreak events, track the origin of the infections, assess the clinical significance of individual strain types, survey their distribution, recognize associations of strain types with specific virulence determinants and/or pathological conditions, assess the role played by the specific components of the virulon, and reveal the phylogeny and the mechanisms through which new strain types have emerged. Despite the many advances that have been made thanks to these flourishing new approaches to molecular epidemiology, a number of critical aspects remain challenging. In this paper, we briefly discuss the current limitations and possible developments of molecular epidemiology methods in the investigation and surveillance of implant infections.

Computer-based coding of free-text job descriptions to efficiently identify occupations in epidemiological studies

PubMed Central

Russ, Daniel E.; Ho, Kwan-Yuet; Colt, Joanne S.; Armenti, Karla R.; Baris, Dalsu; Chow, Wong-Ho; Davis, Faith; Johnson, Alison; Purdue, Mark P.; Karagas, Margaret R.; Schwartz, Kendra; Schwenn, Molly; Silverman, Debra T.; Johnson, Calvin A.; Friesen, Melissa C.

2016-01-01

Background Mapping job titles to standardized occupation classification (SOC) codes is an important step in identifying occupational risk factors in epidemiologic studies. Because manual coding is time-consuming and has moderate reliability, we developed an algorithm called SOCcer (Standardized Occupation Coding for Computer-assisted Epidemiologic Research) to assign SOC-2010 codes based on free-text job description components. Methods Job title and task-based classifiers were developed by comparing job descriptions to multiple sources linking job and task descriptions to SOC codes. An industry-based classifier was developed based on the SOC prevalence within an industry. These classifiers were used in a logistic model trained using 14,983 jobs with expert-assigned SOC codes to obtain empirical weights for an algorithm that scored each SOC/job description. We assigned the highest scoring SOC code to each job. SOCcer was validated in two occupational data sources by comparing SOC codes obtained from SOCcer to expert assigned SOC codes and lead exposure estimates obtained by linking SOC codes to a job-exposure matrix. Results For 11,991 case-control study jobs, SOCcer-assigned codes agreed with 44.5% and 76.3% of manually assigned codes at the 6- and 2-digit level, respectively. Agreement increased with the score, providing a mechanism to identify assignments needing review. Good agreement was observed between lead estimates based on SOCcer and manual SOC assignments (kappa: 0.6–0.8). Poorer performance was observed for inspection job descriptions, which included abbreviations and worksite-specific terminology. Conclusions Although some manual coding will remain necessary, using SOCcer may improve the efficiency of incorporating occupation into large-scale epidemiologic studies. PMID:27102331

Indian Psychiatric epidemiological studies: Learning from the past

PubMed Central

Math, Suresh Bada; Srinivasaraju, Ravindra

2010-01-01

The objective of this paper is to provide a systematic review on the epidemiology of psychiatric disorders in India based on the data published from 1960 to 2009. Extensive search of PubMed, NeuroMed, Indian Journal of Psychiatry website and MEDLARS using search terms “psychiatry” “prevalence”, “community”, and “epidemiology” was done along with the manual search of journals and cross-references. Retrieved articles were systematically selected using specific inclusion and exclusion criteria. Epidemiological studies report prevalence rates for psychiatric disorders varying from 9.5 to 370/1000 population in India. These varying prevalence rates of mental disorders are not only specific to Indian studies but are also seen in international studies. Despite variations in the design of studies, available data from the Indian studies suggests that about 20% of the adult population in the community is affected with one or the other psychiatric disorder. Mental healthcare priorities need to be shifted from psychotic disorders to common mental disorders and from mental hospitals to primary health centers. Increase in invisible mental problems such as suicidal attempts, aggression and violence, widespread use of substances, increasing marital discord and divorce rates emphasize on the need to prioritize and make a paradigm shift in the strategies to promote and provide appropriate mental health services in the community. Future epidemiological research need to focus on the general population from longitudinal prospective involving multi-centers with assessment of disability, co-morbidity, functioning, family burden and quality of life. PMID:21836725

Epidemiologic studies of psychosocial factors associated with quality of life among patients with chronic diseases in Japan.

PubMed

Kojima, Masayo

2012-01-01

A link between affective disturbances and physical disorders has been suggested since the Greco-Roman era. However, evidence supporting an association between mind and body is limited and mostly comes from North America and Europe. Additional local epidemiologic studies are needed so that more evidence can be collected on effective treatments and health management. Epidemiologic studies of Japanese with rheumatoid arthritis (RA) and those on chronic hemodialysis examined the association between psychosocial factors and patient quality of life (QOL). Strong associations among depression, social support, and patient QOL were confirmed, which supports the findings of studies performed in Western countries. In addition, disparities between the perspectives of patients with RA and their doctors were observed. Alexithymia, a personality construct that reflects a deficit in the cognitive processing of emotion, had a stronger independent association with increased risk of 5-year mortality than did depression among patients with chronic hemodialysis. Physiological, biological, and psychosocial factors are associated and independently and interactively determine our health. Epidemiology is a powerful tool for identifying effective points of intervention, after considering all possible confounders. Future studies must clarify how health can be improved by using a psychosocial approach.

Association Between Cannabis and Psychosis: Epidemiologic Evidence.

PubMed

Gage, Suzanne H; Hickman, Matthew; Zammit, Stanley

2016-04-01

Associations between cannabis use and psychotic outcomes are consistently reported, but establishing causality from observational designs can be problematic. We review the evidence from longitudinal studies that have examined this relationship and discuss the epidemiologic evidence for and against interpreting the findings as causal. We also review the evidence identifying groups at particularly high risk of developing psychosis from using cannabis. Overall, evidence from epidemiologic studies provides strong enough evidence to warrant a public health message that cannabis use can increase the risk of psychotic disorders. However, further studies are required to determine the magnitude of this effect, to determine the effect of different strains of cannabis on risk, and to identify high-risk groups particularly susceptible to the effects of cannabis on psychosis. We also discuss complementary epidemiologic methods that can help address these questions. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Epidemiology, Risk Factors, and In-Hospital Mortality of Venous Thromboembolism in Liver Cirrhosis: A Single-Center Retrospective Observational Study

PubMed Central

Zhang, Xintong; Qi, Xingshun; De Stefano, Valerio; Hou, Feifei; Ning, Zheng; Zhao, Jiancheng; Peng, Ying; Li, Jing; Deng, Han; Li, Hongyu; Guo, Xiaozhong

2016-01-01

Background Risk of venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), may be increased in liver cirrhosis. We conducted a single-center study to explore the epidemiology, risk factors, and in-hospital mortality of VTE in Chinese patients with liver cirrhosis. Material/Methods All patients with liver cirrhosis who were consecutively admitted to our hospital between January 2011 and December 2013 were retrospectively included. Results Of 2006 patients with liver cirrhosis included, 9 patients were diagnosed with or developed VTE during hospitalization, including 5 patients with a previous history of DVT, 1 patient with either a previous history of DVT or new onset of PE, and 3 patients with new onset of VTE (PE, n=1; DVT, n=2). Risk factors for VTE included a significantly higher proportion of hypertension and significantly higher red blood cells, hemoglobin, alanine aminotransferase, aspartate aminotransferase, prothrombin time (PT), international normalized ratio (INR), D-dimer, and Child-Pugh scores. The in-hospital mortality was significantly higher in patients with VTE than those without VTE (33.3% [3/9] versus 3.4% [67/1997], P<0.001). Conclusions VTE was observed in 0.4% of patients with liver cirrhosis during hospitalization and it significantly increased the in-hospital mortality. Elevated PT/INR aggravated the risk of VTE. PMID:27009380

Epidemiological study air disaster in Amsterdam (ESADA): study design.

PubMed

Slottje, Pauline; Huizink, Anja C; Twisk, Jos W R; Witteveen, Anke B; van der Ploeg, Henk M; Bramsen, Inge; Smidt, Nynke; Bijlsma, Joost A; Bouter, Lex M; van Mechelen, Willem; Smid, Tjabe

2005-05-30

In 1992, a cargo aircraft crashed into apartment buildings in Amsterdam, killing 43 victims and destroying 266 apartments. In the aftermath there were speculations about the cause of the crash, potential exposures to hazardous materials due to the disaster and the health consequences. Starting in 2000, the Epidemiological Study Air Disaster in Amsterdam (ESADA) aimed to assess the long-term health effects of occupational exposure to this disaster on professional assistance workers. Epidemiological study among all the exposed professional fire-fighters and police officers who performed disaster-related task(s), and hangar workers who sorted the wreckage of the aircraft, as well as reference groups of their non-exposed colleagues who did not perform any disaster-related tasks. The study took place, on average, 8.5 years after the disaster. Questionnaires were used to assess details on occupational exposure to the disaster. Health measures comprised laboratory assessments in urine, blood and saliva, as well as self-reported current health measures, including health-related quality of life, and various physical and psychological symptoms. In this paper we describe and discuss the design of the ESADA. The ESADA will provide additional scientific knowledge on the long-term health effects of technological disasters on professional workers.

[Quality standards for epidemiologic cohort studies : An evaluated catalogue of requirements for the conduct and preparation of cohort studies].

PubMed

Schmidt, Carsten Oliver; Krabbe, Christine E M; Schössow, Janka; Berger, Klaus; Enzenbach, Cornelia; Kamtsiuris, Panagiotis; Schöne, Gina; Houben, Robin; Meisinger, Christa; Bamberg, Fabian; Hendel, Thomas; Selder, Sonja; Nonnemacher, Michael; Moebus, Susanne; Stausberg, Jürgen

2018-01-01

Cohort studies are a longitudinal observational study type. They are firmly established within epidemiology to assess the course of diseases and risk factors. Yet, standards to describe and evaluate quality characteristics of cohort studies need further development. Within the TMF ("Technologie- und Methodenplattform für die vernetzte medizinische Forschung e. V.") project "Quality management standards in cohort studies", a catalogue of requirements was compiled and evaluated, focusing on the preparation and conduct of epidemiologic cohort studies. The catalogue of requirements was established based on a consensus process between representatives of seven German epidemiologic cohort studies. For this purpose, a set of expert meetings (telephone, face-to-face, web-based) was conducted and the importance of each element of the catalogue was assessed as well as its implementation. A catalogue of requirements with 138 requirements was consented. It is structured into ten sections: 1. Study documentation; 2. Selection of instruments; 3. Study implementation, 4. Organizational structure; 5. Qualification and certification; 6. Participant recruitment; 7. Preparation, conduct and follow-up processing of examinations; 8. Study logistics and maintenance, 9. Data capture and data management; 10. Reporting and monitoring. In total, 41 elements were categorized as being essential, 91 as important, and 6 as less important. The catalogue of requirements provides a guideline to improve the preparation and operation of cohort studies. The evaluation of the importance and degree of implementation of requirements depended on the study design. With adaptations, the catalogue might be transferable to other study types.

[Systems epidemiology].

PubMed

Huang, T; Li, L M

2018-05-10

The era of medical big data, translational medicine and precision medicine brings new opportunities for the study of etiology of chronic complex diseases. How to implement evidence-based medicine, translational medicine and precision medicine are the challenges we are facing. Systems epidemiology, a new field of epidemiology, combines medical big data with system biology and examines the statistical model of disease risk, the future risk simulation and prediction using the data at molecular, cellular, population, social and ecological levels. Due to the diversity and complexity of big data sources, the development of study design and analytic methods of systems epidemiology face new challenges and opportunities. This paper summarizes the theoretical basis, concept, objectives, significances, research design and analytic methods of systems epidemiology and its application in the field of public health.

Multicollinearity in Regression Analyses Conducted in Epidemiologic Studies

PubMed Central

Vatcheva, Kristina P.; Lee, MinJae; McCormick, Joseph B.; Rahbar, Mohammad H.

2016-01-01

The adverse impact of ignoring multicollinearity on findings and data interpretation in regression analysis is very well documented in the statistical literature. The failure to identify and report multicollinearity could result in misleading interpretations of the results. A review of epidemiological literature in PubMed from January 2004 to December 2013, illustrated the need for a greater attention to identifying and minimizing the effect of multicollinearity in analysis of data from epidemiologic studies. We used simulated datasets and real life data from the Cameron County Hispanic Cohort to demonstrate the adverse effects of multicollinearity in the regression analysis and encourage researchers to consider the diagnostic for multicollinearity as one of the steps in regression analysis. PMID:27274911

Multicollinearity in Regression Analyses Conducted in Epidemiologic Studies.

PubMed

Vatcheva, Kristina P; Lee, MinJae; McCormick, Joseph B; Rahbar, Mohammad H

2016-04-01

The adverse impact of ignoring multicollinearity on findings and data interpretation in regression analysis is very well documented in the statistical literature. The failure to identify and report multicollinearity could result in misleading interpretations of the results. A review of epidemiological literature in PubMed from January 2004 to December 2013, illustrated the need for a greater attention to identifying and minimizing the effect of multicollinearity in analysis of data from epidemiologic studies. We used simulated datasets and real life data from the Cameron County Hispanic Cohort to demonstrate the adverse effects of multicollinearity in the regression analysis and encourage researchers to consider the diagnostic for multicollinearity as one of the steps in regression analysis.

Epigenetics and epidemiology: models of study and examples.

PubMed

van Veldhoven, Karin; Rahman, Shati; Vineis, Paolo

2014-01-01

Epidemiological studies have successfully identified several environmental causes of disease, but often these studies are limited by methodological problems (e.g. lack of sensitivity and specificity in exposure assessment; confounding). Proposed approaches to improve observational studies of environmental associations are Mendelian randomization and the meet-in-the-middle (MITM) approach. The latter uses signals from the growing field of -omics as putative intermediate biomarkers in the pathogenetic process that links exposure with disease. The first part of this approach consists in the association between exposure and disease. The next step consists in the study of the relationship between (biomarkers of) exposure and intermediate -omic biomarkers of early effect; thirdly, the relation between the disease outcome and intermediate -omic biomarkers is assessed. We propose that when an association is found in all three steps it is possible that there is a casual association. One of the associations that have been investigated extensively in the recent years but is not completely understood is that between environmental endocrine disruptors and breast cancer. Here we present an example of how the "meet-in-the-middle" approach can be used to address the role of endocrine disruptors, by reviewing the relevant literature.

[Clinical-epidemiological study in children with cleft lip palate in a secondary-level hospital].

PubMed

Pons-Bonals, Alicia; Pons-Bonals, Leticia; Hidalgo-Martínez, Sandra Margarita; Sosa-Ferreyra, Carlos Francisco

One of the most common congenital disorders that affects the facial structures is the cleft lip palate (CLP). The aim of this study was to generate the clinical-epidemiological profile of CLP patients from Hospital de Especialidades del Niño y la Mujer (HENM) Dr. Felipe Nuñez Lara, from the Ministry of Health, Queretaro, Mexico, from 2011 to 2014, who received treatment from the Cleft Lip Palate Clinic in order to provide interdisciplinary treatments for CLP patients based on the information from the pediatric records. Retrospective, cross-sectional, observational study using univariate analysis frequencies for qualitative variables; central statistical and dispersion for quantitative variables and clinical profile. One hundred records were reviewed, from which 15 were discarded for being syndromic cases. Epidemiological, clinical, and socio-demographic variables were studied. The epidemiological profile (variables associated with mother's pregnancy, patient's health at birth, nutritional and psychomotor development; family medical records, addictions, and socioeconomic factors) and clinical profile (disease classification by sex, structure, and side; surgeries classification and order in which they took place) of the treated population were registered. The results showed the need to standardize the data registration on medical records to improve the monitoring and treatment of patients and emphasize actions to maintain low incidence of CLP in Queretaro. Copyright © 2017 Hospital Infantil de México Federico Gómez. Publicado por Masson Doyma México S.A. All rights reserved.

Epidemiology as discourse: the politics of development institutions in the Epidemiological Profile of El Salvador

PubMed Central

Aviles, L

2001-01-01

STUDY OBJECTIVE—To determine the ways in which institutions devoted to international development influence epidemiological studies.
DESIGN—This article takes a descriptive epidemiological study of El Salvador, Epidemiological Profile, conducted in 1994 by the US Agency for International Development, as a case study. The methods include discourse analysis in order to uncover the ideological basis of the report and its characteristics as a discourse of development.
SETTING—El Salvador.
RESULTS—The Epidemiological Profile theoretical basis, the epidemiological transition theory, embodies the ethnocentrism of a "colonizer's model of the world." This report follows the logic of a discourse of development by depoliticising development, creating abnormalities, and relying on the development consulting industry. The epidemiological transition theory serves as an ideology that legitimises and dissimulates the international order.
CONCLUSIONS—Even descriptive epidemiological assessments or epidemiological profiles are imbued with theoretical assumptions shaped by the institutional setting under which epidemiological investigations are conducted.


Keywords: El Salvador; politics PMID:11160170

[Epidemiological study of hepatitis A and E viruses in different populations in Uruguay].

PubMed

Cruells, M R; Mescia, G; Gaibisso, R; Ramírez, M; Gutiérrez, M; Kohen, S; González, M; Russi, J; Chiparelli, H; Ucar, L; Pérez, M T

1997-01-01

The hepatitis A and E virus (HAV and HEV) share the fecal-oral mechanism. Hepatitis A is an endemo-epidemic disease in Uruguay but no data on the epidemiologic pattern of the HEV is available. The aims of this study were to update the epidemiologic behavior of the HAV in Montevideo and demonstrate the circulation of the HEV in Uruguay. Two hundred fourteen patients who consulted in the Policlínica de Nutrición y Digestivo were studied, 185 (86%) of whom were anti HAV (HAVAB, Abbot) positive. 81.8% (117/143) of those residents in Montevideo and 95.7% (68/71) of those who were from the inland were anti-HAV positive. From the Montevideo population 55.8% cases under the age of 40 years were anti-HAV positive and occurred in 97.6% of those older (p < 0.001). Considering the health care conditions of the positive patients in Montevideo, 95.6% (43/45) had septic chambers and 75.5% (74/98) disposed of toilet facilities (p < 0.001). It is concluded that although the global prevalence has been maintained since 1982, there is a change in the epidemiologic pattern with greater risk of infection in patients under the age of 40 years proceeding from areas without toilet facilities. The prevalence of total antibodies for HEV (EIA, Abbot) was 2.8% in this population. An association was observed with HAV in 2.2% (4/185). Moreover, a sample of 252 blood donors from the National Blood Service was analyzed with 5 being found to be anti HEV positive, with only 3 (1.2%) being confirmed in the Center for Disease Control in the United States. Although no definitive conclusions may be drawn from the present study, from an epidemiologic point of view, it has been shown that there is evidence of the circulation of HEV in Uruguay, in both the out patient and in blood donor populations.

Epidemiology and the Tobacco Epidemic: How Research on Tobacco and Health Shaped Epidemiology.

PubMed

Samet, Jonathan M

2016-03-01

In this article, I provide a perspective on the tobacco epidemic and epidemiology, describing the impact of the tobacco-caused disease epidemic on the field of epidemiology. Although there is an enormous body of epidemiologic evidence on the associations of smoking with health, little systematic attention has been given to how decades of research have affected epidemiology and its practice. I address the many advances that resulted from epidemiologic research on smoking and health, such as demonstration of the utility of observational designs and important parameters (the odds ratio and the population attributable risk), guidelines for causal inference, and systematic review approaches. I also cover unintended and adverse consequences for the field, including the strategy of doubt creation and the recruitment of epidemiologists by the tobacco industry to serve its mission. The paradigm of evidence-based action for addressing noncommunicable diseases began with the need to address the epidemic of tobacco-caused disease, an imperative for action documented by epidemiologic research. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

PRELIMINARY HEALTH BURDEN ANALYSIS FOR EPIDEMIOLOGIC RECREATIONAL WATER STUDY

EPA Science Inventory

Introduction: The National Epidemiological and Environmental Assessment of Recreational Water Study (NEEAR) offers a rare opportunity for researchers. The study's design involves the collection of health data before and after visiting the beach in conjunction with water quality...

Oligonucleotide (GTG)5 as an epidemiological tool in the study of nontuberculous mycobacteria.

PubMed Central

Cilliers, F J; Warren, R M; Hauman, J H; Wiid, I J; van Helden, P D

1997-01-01

Analysis of restriction fragment length polymorphisms in the genome of Mycobacterium tuberculosis (DNA fingerprinting) has proved to be a useful epidemiological tool in the study of tuberculosis within populations or communities. However, to date, no similar method has been developed to study the epidemiology of nontuberculous mycobacteria (NTM). In this communication, we report that a simple oligonucleotide repeat, (GTG)5, can be used to accurately genotype all species and strains of NTM tested. We suggest that this technology is an easily applied and accurate tool which can be used for the study of the epidemiology of NTM. PMID:9163479

The utility of web mining for epidemiological research: studying the association between parity and cancer risk

PubMed Central

Yoon, Hong-Jun; Xu, Songhua; Han, Xuesong

2016-01-01

Background The World Wide Web has emerged as a powerful data source for epidemiological studies related to infectious disease surveillance. However, its potential for cancer-related epidemiological discoveries is largely unexplored. Methods Using advanced web crawling and tailored information extraction procedures, the authors automatically collected and analyzed the text content of 79 394 online obituary articles published between 1998 and 2014. The collected data included 51 911 cancer (27 330 breast; 9470 lung; 6496 pancreatic; 6342 ovarian; 2273 colon) and 27 483 non-cancer cases. With the derived information, the authors replicated a case-control study design to investigate the association between parity (i.e., childbearing) and cancer risk. Age-adjusted odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for each cancer type and compared to those reported in large-scale epidemiological studies. Results Parity was found to be associated with a significantly reduced risk of breast cancer (OR = 0.78, 95% CI, 0.75-0.82), pancreatic cancer (OR = 0.78, 95% CI, 0.72-0.83), colon cancer (OR = 0.67, 95% CI, 0.60-0.74), and ovarian cancer (OR = 0.58, 95% CI, 0.54-0.62). Marginal association was found for lung cancer risk (OR = 0.87, 95% CI, 0.81-0.92). The linear trend between increased parity and reduced cancer risk was dramatically more pronounced for breast and ovarian cancer than the other cancers included in the analysis. Conclusion This large web-mining study on parity and cancer risk produced findings very similar to those reported with traditional observational studies. It may be used as a promising strategy to generate study hypotheses for guiding and prioritizing future epidemiological studies. PMID:26615183

The utility of web mining for epidemiological research: studying the association between parity and cancer risk.

PubMed

Tourassi, Georgia; Yoon, Hong-Jun; Xu, Songhua; Han, Xuesong

2016-05-01

The World Wide Web has emerged as a powerful data source for epidemiological studies related to infectious disease surveillance. However, its potential for cancer-related epidemiological discoveries is largely unexplored. Using advanced web crawling and tailored information extraction procedures, the authors automatically collected and analyzed the text content of 79 394 online obituary articles published between 1998 and 2014. The collected data included 51 911 cancer (27 330 breast; 9470 lung; 6496 pancreatic; 6342 ovarian; 2273 colon) and 27 483 non-cancer cases. With the derived information, the authors replicated a case-control study design to investigate the association between parity (i.e., childbearing) and cancer risk. Age-adjusted odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for each cancer type and compared to those reported in large-scale epidemiological studies. Parity was found to be associated with a significantly reduced risk of breast cancer (OR = 0.78, 95% CI, 0.75-0.82), pancreatic cancer (OR = 0.78, 95% CI, 0.72-0.83), colon cancer (OR = 0.67, 95% CI, 0.60-0.74), and ovarian cancer (OR = 0.58, 95% CI, 0.54-0.62). Marginal association was found for lung cancer risk (OR = 0.87, 95% CI, 0.81-0.92). The linear trend between increased parity and reduced cancer risk was dramatically more pronounced for breast and ovarian cancer than the other cancers included in the analysis. This large web-mining study on parity and cancer risk produced findings very similar to those reported with traditional observational studies. It may be used as a promising strategy to generate study hypotheses for guiding and prioritizing future epidemiological studies. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Computer-based coding of free-text job descriptions to efficiently identify occupations in epidemiological studies.

PubMed

Russ, Daniel E; Ho, Kwan-Yuet; Colt, Joanne S; Armenti, Karla R; Baris, Dalsu; Chow, Wong-Ho; Davis, Faith; Johnson, Alison; Purdue, Mark P; Karagas, Margaret R; Schwartz, Kendra; Schwenn, Molly; Silverman, Debra T; Johnson, Calvin A; Friesen, Melissa C

2016-06-01

Mapping job titles to standardised occupation classification (SOC) codes is an important step in identifying occupational risk factors in epidemiological studies. Because manual coding is time-consuming and has moderate reliability, we developed an algorithm called SOCcer (Standardized Occupation Coding for Computer-assisted Epidemiologic Research) to assign SOC-2010 codes based on free-text job description components. Job title and task-based classifiers were developed by comparing job descriptions to multiple sources linking job and task descriptions to SOC codes. An industry-based classifier was developed based on the SOC prevalence within an industry. These classifiers were used in a logistic model trained using 14 983 jobs with expert-assigned SOC codes to obtain empirical weights for an algorithm that scored each SOC/job description. We assigned the highest scoring SOC code to each job. SOCcer was validated in 2 occupational data sources by comparing SOC codes obtained from SOCcer to expert assigned SOC codes and lead exposure estimates obtained by linking SOC codes to a job-exposure matrix. For 11 991 case-control study jobs, SOCcer-assigned codes agreed with 44.5% and 76.3% of manually assigned codes at the 6-digit and 2-digit level, respectively. Agreement increased with the score, providing a mechanism to identify assignments needing review. Good agreement was observed between lead estimates based on SOCcer and manual SOC assignments (κ 0.6-0.8). Poorer performance was observed for inspection job descriptions, which included abbreviations and worksite-specific terminology. Although some manual coding will remain necessary, using SOCcer may improve the efficiency of incorporating occupation into large-scale epidemiological studies. 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/

Understanding nutritional epidemiology and its role in policy.

PubMed

Satija, Ambika; Yu, Edward; Willett, Walter C; Hu, Frank B

2015-01-01

Nutritional epidemiology has recently been criticized on several fronts, including the inability to measure diet accurately, and for its reliance on observational studies to address etiologic questions. In addition, several recent meta-analyses with serious methodologic flaws have arrived at erroneous or misleading conclusions, reigniting controversy over formerly settled debates. All of this has raised questions regarding the ability of nutritional epidemiologic studies to inform policy. These criticisms, to a large degree, stem from a misunderstanding of the methodologic issues of the field and the inappropriate use of the drug trial paradigm in nutrition research. The exposure of interest in nutritional epidemiology is human diet, which is a complex system of interacting components that cumulatively affect health. Consequently, nutritional epidemiology constantly faces a unique set of challenges and continually develops specific methodologies to address these. Misunderstanding these issues can lead to the nonconstructive and sometimes naive criticisms we see today. This article aims to clarify common misunderstandings of nutritional epidemiology, address challenges to the field, and discuss the utility of nutritional science in guiding policy by focusing on 5 broad questions commonly asked of the field. © 2015 American Society for Nutrition.

[Bad habits and dysgnathia: epidemiological study].

PubMed

Cordasco, G; Lo Giudice, G; Dolci, E; Romeo, U; Lafronte, G

1989-01-01

The authors refer about an epidemiological survey in 651 children in the school-age. The aim of study is to investigate about the frequency of the bad habits and the pathogenetic relations between these and the development of the dento-maxillo-facial deformities. They point out an incidence of these bad habits in the 35,48% with a predominance of mouth breathers (45,45%). After they discuss the necessity of an early detection of anomalous neuromuscular attitudes.

40 CFR 159.170 - Human epidemiological and exposure studies.

Code of Federal Regulations, 2010 CFR

2010-07-01

... studies. 159.170 Section 159.170 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Information § 159.170 Human epidemiological and exposure studies. Information must be submitted which concerns any study that a person described in § 159.158(a) has concluded, or might reasonably conclude, shows...

Pediatric Allergic Contact Dermatitis: Clinical and Epidemiological Study in a Tertiary Hospital.

PubMed

Ortiz Salvador, J M; Esteve Martínez, A; Subiabre Ferrer, D; Victoria Martínez, A M; de la Cuadra Oyanguren, J; Zaragoza Ninet, V

Few epidemiological studies have investigated the incidence of allergic contact dermatitis in children. Underdiagnosis has been observed in some studies, with many cases in which the condition is not suspected clinically and patch tests are not performed. However, the prevalence of pediatric sensitization to allergens has been reported to be as high as 20%, and the diagnosis should therefore be contemplated as a possibility in this age group. We performed a retrospective analysis of the skin allergy database of the Dermatology Department of Consorcio Hospital General Universitario de Valencia. Children between 0 and 16 years of age diagnosed with allergic contact dermatitis in the previous 15 years (between 2000 and 2015) were included in the analysis. Epidemiological (age, sex, history of atopy) and clinical (site of the lesions, allergen series applied, positive reactions, and their relevance) variables were gathered. Patch tests had been performed on 4,593 patients during the study period. Of these, 265 (6%) were children aged between 0 and 16 years. A positive reaction to at least one of the allergens tested was observed in 144 (54.3%) patients in that group. The allergens most frequently identified were the following (in decreasing order of frequency): thiomersal, cobalt chloride, colophony, paraphenylenediamine, potassium dichromate, mercury, and nickel. The sensitization was considered relevant in 177 (61.3%) cases. More than half of the children studied showed sensitization to 1 or more allergens, with a high percentage of relevant sensitizations. All children with a clinical suspicion of allergic contact dermatitis should be referred for patch testing. As no standardized test series have been developed for this age group, a high level of clinical suspicion and knowledge of the allergens most commonly involved are required when selecting the allergens to be tested. Copyright © 2017 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

CRITICAL REVIEW OF EPIDEMIOLOGIC STUDIES RELATED TO INGESTED ASBESTOS

EPA Science Inventory

Thirteen epidemiologic studies of ingested asbestos conducted in five areas of the U.S. and Canada were reviewed and evaluated for the definitiveness and applicability regarding the development of ambient water quality standards. One or more studies found male or female associati...

Overview of risk assessment in new EPA epidemiology studies

EPA Science Inventory

Since 2003, the Office of Research and Development of the US Environmental Protection Agency has conducted a series of epidemiology studies of water quality and health effects among beach goers at beaches across the United States. These studies are designed to establish associati...

Epidemiologic Study of One Million U.S. Radiation Workers and Veterans

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

Boice, John D.

presentations of the work at scientific meetings. Furthermore, recommendations have been developed for an approach to integrate epidemiologic observations with radiation biology for risk assessment and biological models of radiation effect. The results of this project, as well as ongoing epidemiology studies of US radiation workers and veterans, are providing much-needed insights into complex issues regarding cancer and non-cancer health risks from low dose irradiation, how to apply a "dose and dose rate effectiveness factor" to scale the risks from the A-bomb survivor data to current occupational and environmental circumstances, and how to evaluate risk following intakes of radioactive substances. In addition to application to radiation workers, the results of the studies can provide guidance as society debates the role of nuclear energy and deals with nuclear waste, threats of terrorist attacks with nuclear/radiological devices, the remarkable increase in medical exposures to CT scans and nuclear imaging, and to NASA as radiation protection for astronauts on long-duration mission beyond low-Earth orbit is planned.« less

[Causal analysis approaches in epidemiology].

PubMed

Dumas, O; Siroux, V; Le Moual, N; Varraso, R

2014-02-01

Epidemiological research is mostly based on observational studies. Whether such studies can provide evidence of causation remains discussed. Several causal analysis methods have been developed in epidemiology. This paper aims at presenting an overview of these methods: graphical models, path analysis and its extensions, and models based on the counterfactual approach, with a special emphasis on marginal structural models. Graphical approaches have been developed to allow synthetic representations of supposed causal relationships in a given problem. They serve as qualitative support in the study of causal relationships. The sufficient-component cause model has been developed to deal with the issue of multicausality raised by the emergence of chronic multifactorial diseases. Directed acyclic graphs are mostly used as a visual tool to identify possible confounding sources in a study. Structural equations models, the main extension of path analysis, combine a system of equations and a path diagram, representing a set of possible causal relationships. They allow quantifying direct and indirect effects in a general model in which several relationships can be tested simultaneously. Dynamic path analysis further takes into account the role of time. The counterfactual approach defines causality by comparing the observed event and the counterfactual event (the event that would have been observed if, contrary to the fact, the subject had received a different exposure than the one he actually received). This theoretical approach has shown limits of traditional methods to address some causality questions. In particular, in longitudinal studies, when there is time-varying confounding, classical methods (regressions) may be biased. Marginal structural models have been developed to address this issue. In conclusion, "causal models", though they were developed partly independently, are based on equivalent logical foundations. A crucial step in the application of these models is the

Combined Application of Study Design and Case-Based Learning Comprehensive Model in Epidemiology Teaching

ERIC Educational Resources Information Center

Shi, Xiuquan; Zhou, Yanna; Wang, Haiyan; Wang, Tao; Nie, Chan; Shi, Shangpeng

2017-01-01

This paper aims to conduct the SD-CBL (study design with the case based learning, SD-CBL) in Epidemiology teaching and evaluate its effect. Students from five classes were recruited, and a combined comprehensive teaching model of SD-CBL was used in the "Injury Epidemiology" chapter, while other chapters in "Epidemiology"…

A review of methods used for studying the molecular epidemiology of Brachyspira hyodysenteriae.

PubMed

Zeeh, Friederike; Nathues, Heiko; Frey, Joachim; Muellner, Petra; Fellström, Claes

2017-08-01

Brachyspira (B.) spp. are intestinal spirochaetes isolated from pigs, other mammals, birds and humans. In pigs, seven Brachyspira spp. have been described, i.e. B. hyodysenteriae, B. pilosicoli, B. intermedia, B. murdochii, B. innocens, B. suanatina and B. hampsonii. Brachyspira hyodysenteriae is especially relevant in pigs as it causes swine dysentery and hence considerable economic losses to the pig industry. Furthermore, reduced susceptibility of B. hyodysenteriae to antimicrobials is of increasing concern. The epidemiology of B. hyodysenteriae infections is only partially understood, but different methods for detection, identification and typing have supported recent improvements in knowledge and understanding. In the last years, molecular methods have been increasingly used. Molecular epidemiology links molecular biology with epidemiology, offering unique opportunities to advance the study of diseases. This review is based on papers published in the field of epidemiology and molecular epidemiology of B. hyodysenteriae in pigs. Electronic databases were screened for potentially relevant papers using title and abstract and finally, Barcellos et al. papers were systemically selected and assessed. The review summarises briefly the current knowledge on B. hyodysenteriae epidemiology and elaborates on molecular typing techniques available. Results of the studies are compared and gaps in the knowledge are addressed. Finally, potential areas for future research are proposed. Copyright © 2017 Elsevier B.V. All rights reserved.

Feasibility of future epidemiological studies on possible health effects of mobile phone base stations.

PubMed

Neubauer, Georg; Feychting, Maria; Hamnerius, Yngve; Kheifets, Leeka; Kuster, Niels; Ruiz, Ignacio; Schüz, Joachim; Uberbacher, Richard; Wiart, Joe; Röösli, Martin

2007-04-01

The increasing deployment of mobile communication base stations led to an increasing demand for epidemiological studies on possible health effects of radio frequency emissions. The methodological challenges of such studies have been critically evaluated by a panel of scientists in the fields of radiofrequency engineering/dosimetry and epidemiology. Strengths and weaknesses of previous studies have been identified. Dosimetric concepts and crucial aspects in exposure assessment were evaluated in terms of epidemiological studies on different types of outcomes. We conclude that in principle base station epidemiological studies are feasible. However, the exposure contributions from all relevant radio frequency sources have to be taken into account. The applied exposure assessment method should be piloted and validated. Short to medium term effects on physiology or health related quality of life are best investigated by cohort studies. For long term effects, groups with a potential for high exposure need to first be identified; for immediate effect, human laboratory studies are the preferred approach. (c) 2006 Wiley-Liss, Inc.

Under-reporting bipolar disorder in large-scale epidemiologic studies.

PubMed

Karam, Elie G; Sampson, Nancy; Itani, Lynn; Andrade, Laura Helena; Borges, Guilherme; Chiu, Wai Tat; Florescu, Silvia; Horiguchi, Itsuko; Zarkov, Zahari; Akiskal, Hagop

2014-04-01

To investigate if the prevalence of bipolar disorder in epidemiologic studies is an underestimate, as suggested by clinical studies. We analyzed data from 8 countries that participated in the World Mental Health Survey Initiative (n=47,552). We identified 6.8% and 18.9% of the sample who we think were screened out inappropriately (SCI) from the euphoric and irritable bipolar sections respectively. We compared them to those who were allowed to continue the section (CONT, 2.6% of the sample for euphoric; 1.0% for irritable) and to the reference group (REF, 69.5% of the sample). The SCI group had consistently higher rates of major depression (29.1% vs. 6.4%), earlier age of onset (24.3y vs. 32.4y), more suicide attempts (13.3% vs. 5.9%), and more episodes (4.2 vs. 2.7) than the REF for the euphoric group. Similar findings exist for the irritable group. Also, comorbidity with anxiety, disruptive behavior disorders and substance use were much higher than the REF. As with all epidemiologic studies, recall bias cannot be ruled out. The findings above suggest that a number of the SCI subjects belong to the bipolar group. A revision of instruments used in epidemiologic research will probably prove what clinical studies have been showing that bipolar disorder is more common than has been reported. Copyright © 2014 Elsevier B.V. All rights reserved.

IMPROVING EXPOSURE ASSESSMENT IN DISINFECTION BYPRODUCTS (DBP) EPIDEMIOLOGIC STUDIES

EPA Science Inventory

In 1997, an EPA expert panel was convened to evaluate epidemiologic studies of adverse reproductive or developmental outcomes that may be associated with drinking water DBPs. The panel recommended that further efforts be made in an existing cohort study, headed by Dr. Waller and ...

Implementing a Graduate Certificate Program in Cardiovascular Epidemiology: The Jackson Heart Study

PubMed Central

Campbell Jenkins, Brenda W.; Addison, Clifton; Wilson, Gregory; Young, Lavon; Fields, Regina; Woodberry, Clevette; Payton, Marinelle

2015-01-01

The Jackson Heart Study (JHS) is committed to providing opportunities for expanding the understanding of the epidemiology, diagnosis, prevention, and treatment of cardiovascular diseases. The JHS Graduate Training and Education Center (GTEC) has initiated the Daniel Hale Williams Scholar (DHWS) program where students are afforded the opportunity to interact with epidemiologists and other biomedical scientists to learn to identify, predict, and prevent cardiovascular disease using the Jackson Heart Study data. This study describes the structured programs developed by JHS GTEC seeking to alleviate the shortage of trained professionals in cardiovascular epidemiology by training graduate students while they complete their academic degrees. The DHWS program provides: (1) an enrichment curriculum; (2) a learning community; (3) quarterly seminars; and (4) a Summer Institute. Students attend enrichment activities comprising: (1) Applied Biostatistics; (2) Cardiovascular Disease Epidemiology; (3) Social Epidemiology; (4) Emerging Topics; and (5) Research Writing. Training focuses on developing proficiency in cardiovascular health knowledge. The DHWS program is a unique strategy for incorporating rigorous academic and career-focused training to graduate students and has enabled the acquisition of competencies needed to impact cardiovascular disease management programs. PMID:26703701

Mechanistic and Technical Challenges in Studying the Human Microbiome and Cancer Epidemiology.

PubMed

Verma, Mukesh

2017-04-01

This article reviews the significance of the microbiome in cancer epidemiology, mechanistic and technical challenges in the field, and characterization of the microbiome in different tumor types to identify biomarkers of risk, progression, and prognosis. Publications on the microbiome and cancer epidemiology were reviewed to analyze sample collection and processing, microbiome taxa characterization by 16S ribosomal RNA sequencing, and microbiome metabolite characterization (metabotyping) by nuclear magnetic resonance and mass spectrometry. The analysis identified methodology types, research design, sample types, and issues in integrating data from different platforms. Aerodigestive cancer epidemiology studies conducted by different groups demonstrated the significance of microbiome information in developing approaches to improve health. Challenges exist in sample preparation and processing (eg, standardization of methods for collection and analysis). These challenges relate to technology, data integration from "omics" studies, inherent bias in primer selection during 16S ribosomal RNA sequencing, the need for large consortia with well-characterized biospecimens, cause and effect issues, resilience of microbiota to exposure events (requires longitudinal studies), and expanding studies for fungal and viral diversity (most studies used bacterial 16S ribosomal RNA sequencing for microbiota characterization). Despite these challenges, microbiome and cancer epidemiology studies are significant and may facilitate cancer risk assessment, diagnosis, and prognosis. In the future, clinical trials likely will use microbiota modifications to improve the efficacy of existing treatments.

Mechanistic and Technical Challenges in Studying the Human Microbiome and Cancer Epidemiology

PubMed Central

2016-01-01

This article reviews the significance of the microbiome in cancer epidemiology, mechanistic and technical challenges in the field, and characterization of the microbiome in different tumor types to identify biomarkers of risk, progression, and prognosis. Publications on the microbiome and cancer epidemiology were reviewed to analyze sample collection and processing, microbiome taxa characterization by 16S ribosomal RNA sequencing, and microbiome metabolite characterization (metabotyping) by nuclear magnetic resonance and mass spectrometry. The analysis identified methodology types, research design, sample types, and issues in integrating data from different platforms. Aerodigestive cancer epidemiology studies conducted by different groups demonstrated the significance of microbiome information in developing approaches to improve health. Challenges exist in sample preparation and processing (eg, standardization of methods for collection and analysis). These challenges relate to technology, data integration from “omics” studies, inherent bias in primer selection during 16S ribosomal RNA sequencing, the need for large consortia with well-characterized biospecimens, cause and effect issues, resilience of microbiota to exposure events (requires longitudinal studies), and expanding studies for fungal and viral diversity (most studies used bacterial 16S ribosomal RNA sequencing for microbiota characterization). Despite these challenges, microbiome and cancer epidemiology studies are significant and may facilitate cancer risk assessment, diagnosis, and prognosis. In the future, clinical trials likely will use microbiota modifications to improve the efficacy of existing treatments. PMID:27121074

Use of acetaminophen in relation to the occurrence of cancer: a review of epidemiologic studies.

PubMed

Weiss, Noel S

2016-12-01

Acetaminophen has several pharmacologic properties that suggest it could be carcinogenic in human beings. A number of epidemiologic studies have been conducted to examine whether use of acetaminophen actually predisposes to the occurrence of one or more forms of cancer. There are inherent limitations to many of these studies, including the inaccurate identification of users and nonusers of acetaminophen, relatively short follow-up for cancer incidence, and the potential for confounding by indication. The present manuscript reviews the results of epidemiologic studies of acetaminophen use in relation to cancer incidence published through the end of 2015. The limitations of the underlying studies notwithstanding, some interim conclusions can be reached. For all but several forms of cancer, there is no suggestion that persons who have taken acetaminophen are at altered risk, even persons who have consumed a large quantity of the drug or those who have taken it for an extended duration. While in some studies the incidence of renal cell carcinoma has been observed to be increased among acetaminophen users, several other studies have failed to observe any such association; the reason for the discrepant findings is unclear. Some of the small number of studies that have presented data on the incidence of lymphoma, leukemia, and plasma cell disorders have found the risk to be modestly higher in users than nonusers of acetaminophen, but the results of other studies of these malignancies will be needed to gauge the possible role of publication bias as the basis for the positive results.

Epidemiologic studies of glyphosate and cancer: a review.

PubMed

Mink, Pamela J; Mandel, Jack S; Sceurman, Bonnielin K; Lundin, Jessica I

2012-08-01

The United States Environmental Protection Agency and other regulatory agencies around the world have registered glyphosate as a broad-spectrum herbicide for use on multiple food and non-food use crops. Glyphosate is widely considered by regulatory authorities and scientific bodies to have no carcinogenic potential, based primarily on results of carcinogenicity studies of rats and mice. To examine potential cancer risks in humans, we reviewed the epidemiologic literature to evaluate whether exposure to glyphosate is associated causally with cancer risk in humans. We also reviewed relevant methodological and biomonitoring studies of glyphosate. Seven cohort studies and fourteen case-control studies examined the association between glyphosate and one or more cancer outcomes. Our review found no consistent pattern of positive associations indicating a causal relationship between total cancer (in adults or children) or any site-specific cancer and exposure to glyphosate. Data from biomonitoring studies underscore the importance of exposure assessment in epidemiologic studies, and indicate that studies should incorporate not only duration and frequency of pesticide use, but also type of pesticide formulation. Because generic exposure assessments likely lead to exposure misclassification, it is recommended that exposure algorithms be validated with biomonitoring data. Copyright © 2012 Elsevier Inc. All rights reserved.

The second molecular epidemiological study of HIV infection in Mongolia between 2010 and 2016.

PubMed

Jagdagsuren, Davaalkham; Hayashida, Tsunefusa; Takano, Misao; Gombo, Erdenetuya; Zayasaikhan, Setsen; Kanayama, Naomi; Tsuchiya, Kiyoto; Oka, Shinichi

2017-01-01

Our previous 2005-2009 molecular epidemiological study in Mongolia identified a hot spot of HIV-1 transmission in men who have sex with men (MSM). To control the infection, we collaborated with NGOs to promote safer sex and HIV testing since mid-2010. In this study, we carried out the second molecular epidemiological survey between 2010 and 2016 to determine the status of HIV-1 infection in Mongolia. The study included 143 new cases of HIV-1 infection. Viral RNA was extracted from stocked plasma samples and sequenced for the pol and the env regions using the Sanger method. Near-full length sequencing using MiSeq was performed in 3 patients who were suspected to be infected with recombinant HIV-1. Phylogenetic analysis was performed using the neighbor-joining method and Bayesian Markov chain Monte Carlo method. MSM was the main transmission route in the previous and current studies. However, heterosexual route showed a significant increase in recent years. Phylogenetic analysis documented three taxa; Mongolian B, Korean B, and CRF51_01B, though the former two were also observed in the previous study. CRF51_01B, which originated from Singapore and Malaysia, was confirmed by near-full length sequencing. Although these strains were mainly detected in MSM, they were also found in increasing numbers of heterosexual males and females. Bayesian phylogenetic analysis estimated transmission of CRF51_01B into Mongolia around early 2000s. An extended Bayesian skyline plot showed a rapid increase in the effective population size of Mongolian B cluster around 2004 and that of CRF51_01B cluster around 2011. HIV-1 infection might expand to the general population in Mongolia. Our study documented a new cluster of HIV-1 transmission, enhancing our understanding of the epidemiological status of HIV-1 in Mongolia.

Epidemiology for the nuclear medicine technologist.

PubMed

Bolus, N E

2001-09-01

The purpose of this article is to introduce the nuclear medicine technologist to the field of epidemiology. There are many applications of epidemiology in nuclear medicine, including research studies that deal with the causes of disease or ways to prevent disease from occurring and investigating the possible effects of ionizing radiation on occupational workers and the general public. One use of an epidemiologic study is to suggest ways to reduce the occurrence of a disease. After reading this article, the nuclear medicine technologist will be familiar with: a) the history and underlying assumptions of epidemiology, b) types of epidemiologic studies, c) what is a valid statistical association for an epidemiologic study, d) proper judgment of cause and effect relationships, e) definitions of epidemiologic terms, and f) an example of a nuclear medicine research study.

The utility of observational studies in clinical decision making: lessons learned from statin trials.

PubMed

Foody, JoAnne M; Mendys, Phillip M; Liu, Larry Z; Simpson, Ross J

2010-05-01

Contemporary clinical decision making is well supported by a wide variety of information sources, including clinical practice guidelines, position papers, and insights from randomized controlled trials (RCTs). Much of our fundamental understanding of cardiovascular risk factors is based on multiple observations from major epidemiologic studies, such as The Seven Country Studies and the US-based Framingham Heart Study. These studies provided the framework for the development of clinical practice guidelines, including the National Cholesterol Education Program Adult Treatment Panel series. The objective of this article is to highlight the value of observational studies as a complement to clinical trial data for clinical decision making in real-world practice. Although RCTs are still the benchmark for assessing clinical efficacy and safety of a specific therapeutic approach, they may be of limited utility to practitioners who must then adapt the lessons learned from the trial into the patient care environment. The use of well-structured observational studies can improve our understanding of the translation of clinical trials into clinical practice, as demonstrated here with the example of statins. Although such studies have their own limitations, improved techniques for design and analysis have reduced the impact of bias and confounders. The introduction of the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines has provided more uniformity for such studies. When used together with RCTs, observational studies can enhance our understanding of effectiveness and utility in real-world clinical practice. In the examples of statin observational studies, the results suggest that relative effectiveness of different statins and potential impact of switching statins should be carefully considered in treating individual patients by practicing physicians.

Using whole genome sequencing to study American foulbrood epidemiology in honeybees

PubMed Central

Ågren, Joakim; Schäfer, Marc Oliver

2017-01-01

American foulbrood (AFB), caused by Paenibacillus larvae, is a devastating disease in honeybees. In most countries, the disease is controlled through compulsory burning of symptomatic colonies causing major economic losses in apiculture. The pathogen is endemic to honeybees world-wide and is readily transmitted via the movement of hive equipment or bees. Molecular epidemiology of AFB currently largely relies on placing isolates in one of four ERIC-genotypes. However, a more powerful alternative is multi-locus sequence typing (MLST) using whole-genome sequencing (WGS), which allows for high-resolution studies of disease outbreaks. To evaluate WGS as a tool for AFB-epidemiology, we applied core genome MLST (cgMLST) on isolates from a recent outbreak of AFB in Sweden. The high resolution of the cgMLST allowed different bacterial clones involved in the disease outbreak to be identified and to trace the source of infection. The source was found to be a beekeeper who had sold bees to two other beekeepers, proving the epidemiological link between them. No such conclusion could have been made using conventional MLST or ERIC-typing. This is the first time that WGS has been used to study the epidemiology of AFB. The results show that the technique is very powerful for high-resolution tracing of AFB-outbreaks. PMID:29140998

Update on the Epidemiology of Concussion/Mild Traumatic Brain Injury.

PubMed

Voss, Jameson D; Connolly, Joseph; Schwab, Karen A; Scher, Ann I

2015-07-01

Mild traumatic injuries to the brain (e.g., concussion) are common and have been recognized since antiquity, although definitions have varied historically. Nonetheless, studying the epidemiology of concussion helps clarify the overall importance, risk factors, and at-risk populations for this injury. The present review will focus on recent findings related to the epidemiology of concussion including definition controversies, incidence, and patterns in the population overall and in the military and athlete populations specifically. Finally, as this is an area of active research, we will discuss how future epidemiologic observations hold promise for gaining greater clarity about concussion and mild traumatic brain injury.

A systematic review of population based epidemiological studies in Myasthenia Gravis

PubMed Central

2010-01-01

Background The aim was to collate all myasthenia gravis (MG) epidemiological studies including AChR MG and MuSK MG specific studies. To synthesize data on incidence rate (IR), prevalence rate (PR) and mortality rate (MR) of the condition and investigate the influence of environmental and technical factors on any trends or variation observed. Methods Studies were identified using multiple sources and meta-analysis performed to calculate pooled estimates for IR, PR and MR. Results 55 studies performed between 1950 and 2007 were included, representing 1.7 billion population-years. For All MG estimated pooled IR (eIR): 5.3 per million person-years (C.I.:4.4, 6.1), range: 1.7 to 21.3; estimated pooled PR: 77.7 per million persons (C.I.:64.0, 94.3), range 15 to 179; MR range 0.1 to 0.9 per millions person-years. AChR MG eIR: 7.3 (C.I.:5.5, 7.8), range: 4.3 to 18.0; MuSK MG IR range: 0.1 to 0.32. However marked variation persisted between populations studied with similar methodology and in similar areas. Conclusions We report marked variation in observed frequencies of MG. We show evidence of increasing frequency of MG with year of study and improved study quality. This probably reflects improved case ascertainment. But other factors must also influence disease onset resulting in the observed variation in IR across geographically and genetically similar populations. PMID:20565885

Mandibular Fractures in Iraq: An Epidemiological Study

PubMed Central

Bede, Salwan

2014-01-01

The purpose of this study was to evaluate the epidemiological characteristics of the mandibular fractures relating to gender, age, the etiology of injury, and the rendered treatment modalities and complications. The data of the patients who sustained mandibular fractures were retrieved and were analyzed retrospectively, and based on these data a descriptive analysis was conducted. A total of 112 patients were included in this study; the most common cause was road traffic accidents (RTAs) followed by assaults and missile injuries. The most frequently involved age group was 11 to 20 years, treatment modalities included conservative, closed reduction and indirect fixation, and open reduction and internal fixation (ORIF) in 11.6, 79.5, and 8.9% of the cases, respectively. Most of the major complications were injury related. This study showed RTAs to be the most frequent cause followed by assaults, it also showed that a high percentage of assault victims were females mainly of low socioeconomic status. Another distinguishing feature in this study was the high incidence of missile injuries in the form of bullets and blasts. Closed reduction still has an important role in the treatment of fractures of mandible especially when the necessary equipments for ORIF are not readily available. A higher complication rate was observed in patients diagnosed with multiple and comminuted fractures as well as those caused by violence in the form of missile and assault injuries. PMID:25709754

Epidemiological and morphological studies of double-chambered right ventricle in dogs.

PubMed

Fukushima, Ryuji; Tanaka, Ryou; Suzuki, Shuji; Hamabe, Rina; Machida, Noboru; Nakao, Shu; Saida, Yuto; Takashima, Kazuaki; Matsumoto, Hirotaka; Koyama, Hidekazu; Hirose, Hisashi; Yamane, Yoshihisa

2011-10-01

The double-chambered right ventricle (DCRV) is a rare congenital cardiac disease in dogs, and its detailed epidemiological and morphological features are not clearly understood. By investigating the profile, clinical signs, and characteristics of examination findings of eleven dogs with DCRV by means of a retrospective study, we attempted to clarify the epidemiology and morphology of the condition. The study group consisted of nine males and two females. Breeds included Pug (n=3), Miniature Dachshund (n=1), French Bull-dog (n=1), Shiba (n=1), and Retrievers (n=5). The attachment site of the anomalous muscular bundle was continuous with the cardiac apex in nine dogs, and it was attached to the right ventricle free wall in the other two dogs. In dogs with DCRV, at least one of the following conditions was present concurrently: congenital or acquired tricuspid valve regurgitation (TR), ventricular septal defect, and atrial septal defect. Also, the pressure difference between the two chambers increased over time, and progressive right-sided heart failure was observed. In summary, DCRV occurs in small breeds of dog as well as in large breeds of dog and it may be more prevalent in males. The existence of two types of DCRV in dogs was established. Dog with DCRVs will have a high incidence of concurrent cardiac abnormalities. Concurrent TR may be either congenital or acquired. DCRV is a congenital disorder, but the clinical condition progresses as the dog develops.

The Role of DNA Methylation in Cardiovascular Risk and Disease: Methodological Aspects, Study Design, and Data Analysis for Epidemiological Studies.

PubMed

Zhong, Jia; Agha, Golareh; Baccarelli, Andrea A

2016-01-08

Epidemiological studies have demonstrated that genetic, environmental, behavioral, and clinical factors contribute to cardiovascular disease development. How these risk factors interact at the cellular level to cause cardiovascular disease is not well known. Epigenetic epidemiology enables researchers to explore critical links between genomic coding, modifiable exposures, and manifestation of disease phenotype. One epigenetic link, DNA methylation, is potentially an important mechanism underlying these associations. In the past decade, there has been a significant increase in the number of epidemiological studies investigating cardiovascular risk factors and outcomes in relation to DNA methylation, but many gaps remain in our understanding of the underlying cause and biological implications. In this review, we provide a brief overview of the biology and mechanisms of DNA methylation and its role in cardiovascular disease. In addition, we summarize the current evidence base in epigenetic epidemiology studies relevant to cardiovascular health and disease and discuss the limitations, challenges, and future directions of the field. Finally, we provide guidelines for well-designed epigenetic epidemiology studies, with particular focus on methodological aspects, study design, and analytical challenges. © 2016 American Heart Association, Inc.

Genetic variation and willingness to participate in epidemiologic research: data from three studies.

PubMed

Bhatti, Parveen; Sigurdson, Alice J; Wang, Sophia S; Chen, Jinbo; Rothman, Nathaniel; Hartge, Patricia; Bergen, Andrew W; Landi, Maria Teresa

2005-10-01

The differences in common genetic polymorphism frequencies by willingness to participate in epidemiologic studies are unexplored, but the same threats to internal validity operate as for studies with nongenetic information. We analyzed single nucleotide polymorphism genotypes, haplotypes, and short tandem repeats among control groups from three studies with different recruitment designs that included early, late, and never questionnaire responders, one or more participation incentives, and blood or buccal DNA collection. Among 2,955 individuals, we compared 108 genotypes, 8 haplotypes, and 9 to 15 short tandem repeats by respondent type. Among our main comparisons, single nucleotide polymorphism genotype frequencies differed significantly (P < 0.05) between respondent groups in six instances, with 13 expected by chance alone. When comparing the odds of carrying a variant among the various response groups, 19 odds ratios were /=1.40, levels that might be notably different. Among the various respondent group comparisons, haplotype and short tandem repeat frequencies were not significantly different by willingness to participate. We observed little evidence to suggest that genotype differences underlie response characteristics in molecular epidemiologic studies, but a greater variety of genes should be examined, including those related to behavioral traits potentially associated with willingness to participate. To the extent possible, investigators should evaluate their own genetic data for bias in response categories.

Understanding Nutritional Epidemiology and Its Role in Policy12

PubMed Central

Satija, Ambika; Yu, Edward; Willett, Walter C; Hu, Frank B

2015-01-01

Nutritional epidemiology has recently been criticized on several fronts, including the inability to measure diet accurately, and for its reliance on observational studies to address etiologic questions. In addition, several recent meta-analyses with serious methodologic flaws have arrived at erroneous or misleading conclusions, reigniting controversy over formerly settled debates. All of this has raised questions regarding the ability of nutritional epidemiologic studies to inform policy. These criticisms, to a large degree, stem from a misunderstanding of the methodologic issues of the field and the inappropriate use of the drug trial paradigm in nutrition research. The exposure of interest in nutritional epidemiology is human diet, which is a complex system of interacting components that cumulatively affect health. Consequently, nutritional epidemiology constantly faces a unique set of challenges and continually develops specific methodologies to address these. Misunderstanding these issues can lead to the nonconstructive and sometimes naive criticisms we see today. This article aims to clarify common misunderstandings of nutritional epidemiology, address challenges to the field, and discuss the utility of nutritional science in guiding policy by focusing on 5 broad questions commonly asked of the field. PMID:25593140

Preliminary report from the World Health Organisation Chest Radiography in Epidemiological Studies project.

PubMed

Mahomed, Nasreen; Fancourt, Nicholas; de Campo, John; de Campo, Margaret; Akano, Aliu; Cherian, Thomas; Cohen, Olivia G; Greenberg, David; Lacey, Stephen; Kohli, Neera; Lederman, Henrique M; Madhi, Shabir A; Manduku, Veronica; McCollum, Eric D; Park, Kate; Ribo-Aristizabal, Jose Luis; Bar-Zeev, Naor; O'Brien, Katherine L; Mulholland, Kim

2017-10-01

Childhood pneumonia is among the leading infectious causes of mortality in children younger than 5 years of age globally. Streptococcus pneumoniae (pneumococcus) is the leading infectious cause of childhood bacterial pneumonia. The diagnosis of childhood pneumonia remains a critical epidemiological task for monitoring vaccine and treatment program effectiveness. The chest radiograph remains the most readily available and common imaging modality to assess childhood pneumonia. In 1997, the World Health Organization Radiology Working Group was established to provide a consensus method for the standardized definition for the interpretation of pediatric frontal chest radiographs, for use in bacterial vaccine efficacy trials in children. The definition was not designed for use in individual patient clinical management because of its emphasis on specificity at the expense of sensitivity. These definitions and endpoint conclusions were published in 2001 and an analysis of observer variation for these conclusions using a reference library of chest radiographs was published in 2005. In response to the technical needs identified through subsequent meetings, the World Health Organization Chest Radiography in Epidemiological Studies (CRES) project was initiated and is designed to be a continuation of the World Health Organization Radiology Working Group. The aims of the World Health Organization CRES project are to clarify the definitions used in the World Health Organization defined standardized interpretation of pediatric chest radiographs in bacterial vaccine impact and pneumonia epidemiological studies, reinforce the focus on reproducible chest radiograph readings, provide training and support with World Health Organization defined standardized interpretation of chest radiographs and develop guidelines and tools for investigators and site staff to assist in obtaining high-quality chest radiographs.

ESTIMATING RESIDENTIAL EXPOSURE TO DRINKING WATER ARSENIC IN INNER MONGOLIA, CHINA FOR EPIDEMIOLOGIC STUDIES

EPA Science Inventory

ESTIMATING RESIDENTIAL EXPOSURE TO DRINKING WATER ARSENIC IN INNER MONGOLIA, CHINA FOR EPIDEMIOLOGIC STUDIES

Richard Kwok1, Pauline Mendola1 Zhixiong Ning2, Zhiyi Liu2 and Judy Mumford1

1) Epidemiology and Biomarkers Branch, Human Studies Division, NHEERL, US EPA, R...

Assessing the first wave of epidemiological studies of nanomaterial workers

NASA Astrophysics Data System (ADS)

Liou, Saou-Hsing; Tsai, Candace S. J.; Pelclova, Daniela; Schubauer-Berigan, Mary K.; Schulte, Paul A.

2015-10-01

The results of early animal studies of engineered nanomaterials (ENMs) and air pollution epidemiology suggest that it is important to assess the health of ENM workers. Initial epidemiological studies of workers' exposure to ENMs (<100 nm) are reviewed and characterized for their study designs, findings, and limitations. Of the 15 studies, 11 were cross-sectional, 4 were longitudinal (1 was both cross-sectional and longitudinal in design), and 1 was a descriptive pilot study. Generally, the studies used biologic markers as the dependent variables. All 11 cross-sectional studies showed a positive relationship between various biomarkers and ENM exposures. Three of the four longitudinal studies showed a negative relationship; the fourth showed positive findings after a 1-year follow-up. Each study considered exposure to ENMs as the independent variable. Exposure was assessed by mass concentration in 10 studies and by particle count in six studies. Six of them assessed both mass and particle concentrations. Some of the studies had limited exposure data because of inadequate exposure assessment. Generally, exposure levels were not very high in comparison to those in human inhalation chamber studies, but there were some exceptions. Most studies involved a small sample size, from 2 to 258 exposed workers. These studies represent the first wave of epidemiological studies of ENM workers. They are limited by small numbers of participants, inconsistent (and in some cases inadequate) exposure assessments, generally low exposures, and short intervals between exposure and effect. Still, these studies are a foundation for future work; they provide insight into where ENM workers are experiencing potentially adverse effects that might be related to ENM exposures.

Defining Chronic Cough: A Systematic Review of the Epidemiological Literature

PubMed Central

Song, Woo-Jung; Chang, Yoon-Seok; Faruqi, Shoaib; Kang, Min-Koo; Kim, Ju-Young; Kang, Min-Gyu; Kim, Sujeong; Jo, Eun-Jung; Lee, Seung-Eun; Kim, Min-Hye; Plevkova, Jana; Park, Heung-Woo

2016-01-01

Purpose Recent evidence suggests a global burden of chronic cough in general populations. However, the definitions vary greatly among epidemiological studies, and none have been validated for clinical relevance. We aimed to examine previous epidemiological definitions in detail and explore the operational characteristics. Methods A systematic review was conducted for epidemiological surveys that reported the prevalence of chronic cough in general adult populations during the years 1980 to 2013. A literature search was performed on Pubmed and Embase without language restriction. Epidemiological definitions for chronic cough were classified according to their components, such as cutoff duration. Meta-analyses were performed for the male-to-female ratio of chronic cough prevalence to explore operational characteristics of epidemiological definitions. Results A total of 70 studies were included in the systematic review. The most common epidemiological definition was identified as 'cough ≥3 months' duration without specification of phlegm (n=50); however, it conflicted with the cutoff duration in current clinical guidelines (cough ≥8 weeks). Meta-analyses were performed for the male-to-female ratio of chronic cough among 28 studies that reported sex-specific prevalence using the most common definition. The pooled male-to-female odds ratio was 1.26 (95% confidence interval 0.92-1.73) with significant heterogeneity (I2=96%, P<0.001), which was in contrast to clinical observations of female predominance from specialist clinics. Subgroup analyses did not reverse the ratio or reduce the heterogeneity. Conclusions This study identified major issues in defining chronic cough in future epidemiological studies. The conflict between epidemiological and clinical diagnostic criteria needs to be resolved. The unexpected difference in the gender predominance between the community and clinics warrants further studies. Clinical validation of the existing definition is required

Chromium and disease: review of epidemiologic studies with particular reference to etiologic information provided by measures of exposure.

PubMed Central

Lees, P S

1991-01-01

Dozens of epidemiologic studies have been conducted since the late 1940s in an attempt to elucidate the relationship between exposure to chromium compounds and increased rates of certain cancers observed in several industries. The relationship between employment in industries producing chromium compounds from chromite ore and lung cancer has been well established in numerous studies. The relationship between exposure to certain chromium-based pigments and chromic acid and lung cancer, although not as strong, is fairly well accepted. The data concerning emissions from stainless-steel manufacturing and disease are contradictory. Although individual studies have indicated excesses of gastrointestinal and occasionally other cancers in these industries, results are not consistent and not universally accepted. There is general agreement that chromite ore does not have an associated risk of cancer. Although the chromium compound (or compounds) responsible for disease have yet to be identified, there is general agreement that hexavalent species are responsible for these diseases and that the trivalent species are not. Hypotheses about the carcinogenicity of specific chromium compounds generally relate to their solubility in body fluids. These hypotheses, however, have generally been produced as a result of toxicologic, not epidemiologic, investigation. Well-designed epidemiologic studies incorporating detailed assessments of worker exposures have the potential to help elucidate causality, identify specific carcinogenic compounds, and quantify risk in humans, eliminating the need to extrapolate from animal data. Although the need for exposure data crucial to this effort was identified in the earliest epidemiologic studies of chromium, such studies have not been conducted. As a result, little more is known today about the relationship between this chemical and disease in humans than was known 40 years ago. PMID:1935857

Informing subjects of epidemiologic study results. Children's Cancer Group.

PubMed

Bunin, G R; Kazak, A E; Mitelman, O

1996-04-01

To assess the feasibility and process of providing feedback to parents regarding the results of epidemiologic research, in particular to look at the importance and clarity of the information provided, parental reactions to the results, and utilization of the data provided. Parents who participated in an epidemiologic study of pediatric brain tumors (patient and control mothers) were sent a letter summarizing the results of the study and the Parent Study Results Survey to complete and return. The final sample used for analyses was 109 (patient) and 90 (control) mothers. Analyses were conducted to determine differences between patient and control mothers and differences among subsets defined by educational level and vital status of the patient. Mothers rated the importance and clarity of the information very highly, although patient mothers were more likely than control mothers to want more information and a telephone contact. Patient and control mothers were similar in reported sadness, anxiety, and being overwhelmed, but patient mothers felt less satisfied and relieved. Patient mothers expressed feeling more guilt nad anger than control mothers, although even the levels among the patient mothers were only moderate. Close to half of all mothers commented on the inconclusiveness of the study results. Nearly all mothers indicated they would suggest that other parents participate in epidemiologic research. It is valuable to many parents that they receive information about results of research in which they have participated. We found little evidence of strong negative effects to a detailed feedback letter. We recommend that evaluative data be used to guide the process of informing research participants about study results and that investigators consider making feedback letters a standard part of research protocols.

The big data potential of epidemiological studies for criminology and forensics.

PubMed

DeLisi, Matt

2018-07-01

Big data, the analysis of original datasets with large samples ranging from ∼30,000 to one million participants to mine unexplored data, has been under-utilized in criminology. However, there have been recent calls for greater synthesis between epidemiology and criminology and a small number of scholars have utilized epidemiological studies that were designed to measure alcohol and substance use to harvest behavioral and psychiatric measures that relate to the study of crime. These studies have been helpful in producing knowledge about the most serious, violent, and chronic offenders, but applications to more pathological forensic populations is lagging. Unfortunately, big data relating to crime and justice are restricted and limited to criminal justice purposes and not easily available to the research community. Thus, the study of criminal and forensic populations is limited in terms of data volume, velocity, and variety. Additional forays into epidemiology, increased use of available online judicial and correctional data, and unknown new frontiers are needed to bring criminology up to speed in the big data arena. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Methodological considerations in observational comparative effectiveness research for implantable medical devices: an epidemiologic perspective.

PubMed

Jalbert, Jessica J; Ritchey, Mary Elizabeth; Mi, Xiaojuan; Chen, Chih-Ying; Hammill, Bradley G; Curtis, Lesley H; Setoguchi, Soko

2014-11-01

Medical devices play a vital role in diagnosing, treating, and preventing diseases and are an integral part of the health-care system. Many devices, including implantable medical devices, enter the market through a regulatory pathway that was not designed to assure safety and effectiveness. Several recent studies and high-profile device recalls have demonstrated the need for well-designed, valid postmarketing studies of medical devices. Medical device epidemiology is a relatively new field compared with pharmacoepidemiology, which for decades has been developed to assess the safety and effectiveness of medications. Many methodological considerations in pharmacoepidemiology apply to medical device epidemiology. Fundamental differences in mechanisms of action and use and in how exposure data are captured mean that comparative effectiveness studies of medical devices often necessitate additional and different considerations. In this paper, we discuss some of the most salient issues encountered in conducting comparative effectiveness research on implantable devices. We discuss special methodological considerations regarding the use of data sources, exposure and outcome definitions, timing of exposure, and sources of bias. © The Author 2014. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Immortal time bias in pharmaco-epidemiology.

PubMed

Suissa, Samy

2008-02-15

Immortal time is a span of cohort follow-up during which, because of exposure definition, the outcome under study could not occur. Bias from immortal time was first identified in the 1970s in epidemiology in the context of cohort studies of the survival benefit of heart transplantation. It recently resurfaced in pharmaco-epidemiology, with several observational studies reporting that various medications can be extremely effective at reducing morbidity and mortality. These studies, while using different cohort designs, all involved some form of immortal time and the corresponding bias. In this paper, the author describes various cohort study designs leading to this bias, quantifies its magnitude under different survival distributions, and illustrates it by using data from a cohort of lung cancer patients. The author shows that for time-based, event-based, and exposure-based cohort definitions, the bias in the rate ratio resulting from misclassified or excluded immortal time increases proportionately to the duration of immortal time. The bias is more pronounced with a decreasing hazard function for the outcome event, as illustrated with the Weibull distribution compared with a constant hazard from the exponential distribution. In conclusion, observational studies of drug benefit in which computerized databases are used must be designed and analyzed properly to avoid immortal time bias.

Epidemiological Study of Fusarium Species Causing Invasive and Superficial Fusariosis in Japan.

PubMed

Muraosa, Yasunori; Oguchi, Misato; Yahiro, Maki; Watanabe, Akira; Yaguchi, Takashi; Kamei, Katsuhiko

2017-01-01

In Japan, Fusarium species are known etiological agents of human fungal infection; however, there has been no report of a large-scale epidemiological study on the etiological agents of fusariosis. A total of 73 Fusarium isolates from patients with invasive fusariosis (IF, n= 36) or superficial fusariosis (SF, n= 37), which were obtained at hospitals located in 28 prefectures in Japan between 1998 and 2015, were used for this study. Fusarium isolates were identified using Fusarium- and Fusarium solani species complex (FSSC) -specific real-time PCR and partial DNA sequences of the elongation factor-1 alpha (EF-1α) gene and the nuclear ribosomal internal transcribed spacer (ITS) region. FSSC was predominately isolated from both patients with IF and SF (IF, 77.8% and SF, 67.6%). Distribution of the phylogenetic species of FSSC isolates from patients with IF and SF exhibited different spectra; specifically, F. keratoplasticum (FSSC 2) (25.0%) was the most frequent isolate from patients with IF, whereas F. falciforme (FSSC 3+4) (32.4%) was the most frequent isolate from patients with SF. Fusarium sp. (FSSC 5) was the second most frequent isolate from both patients with IF and SF (IF, 22.2% and SF, 24.3%). Notably, F. petroliphilum (FSSC 1) was isolated only from patients with IF. Each species was isolated from a broad geographic area, and an epidemic was not observed. This is the first epidemiological study of Fusarium species causing IF and SF in Japan.

Psychiatric epidemiology in India.

PubMed

Math, Suresh Bada; Chandrashekar, C R; Bhugra, Dinesh

2007-09-01

Epidemiological studies report prevalence rates for psychiatric disorders from 9.5 to 370/1000 populations in India. This review critically evaluates the prevalence rate of mental disorders as reported in Indian epidemiological studies. Extensive search of PubMed, NeuroMed and MEDLARS using search terms "psychiatry" and "epidemiology" was done. Manual search of literature was also done. Retrieved articles were systematically selected using inclusion and exclusion criteria. Only sixteen prevalence studies fulfilled the study criteria. Most of the epidemiological studies done in India neglected anxiety disorders, substance dependence disorders, co-morbidity and dual diagnosis. The use of poor sensitive screening instruments, single informant and systematic underreporting has added to the discrepancy in the prevalence rate. The prevalence of mental disorders reported in epidemiological surveys can be considered lower estimates rather than accurate reflections of the true prevalence in the population. Researchers have focused on broad non-specific, non-modifiable risk factors, such as age, gender and social class. Future research focused on the general population, longitudinal (prospective), multi-centre, co-morbid studies, assessment of disability, functioning, family burden and quality of life studies involving a clinical service providing approach, is required.

The Biomonitoring, Environmental Epidemiology, and Short-Lived Chemicals (BEES-C) Instrument for Assessing Study Quality

EPA Science Inventory

Environmental epidemiology studies can be an effective means to assess impacts on human health from exposure to environmental stressors. Exposure scenarios are often extremely complex and proper assessment is critical for interpreting epidemiological study results. Biomarkers are...

[Epidemiology's and epidemiologists' vices and virtues].

PubMed

Gennaro, Valerio; Ricci, Paolo; Levis, Angelo Gino; Crosignani, Paolo

2009-01-01

Epidemiology is a public health oriented discipline and is aimed to detect the spatial, temporal, social and causal distribution of diseases in the human population, in order to promote timely and effective preventive solutions. This paper highlights some gold standard of the epidemiological method and suggests some considerations for a critical comprehension of epidemiological studies, in particular those that deny or minimize the existence of public health risks. This paper will focus on some crucial elements such as definition, attribution, misclassification and underestimation of the harmful exposures caused by a multitude of factors, undervaluation of the possible interactions among harmful agents (even when law limits are respected), selection of exposed populations, insufficient number of studied diseases, importance of the right comparisons between similar groups when the reference population is used, disproportion between shortness of follow-up in respect with long latency period of the studied diseases, including cancer. This paper also observes that many epidemiologists carry out confirmative studies rather than exploratory ones, and they end to both underestimate and underevaluate the multiplicity of the causal associations in favour of a reductive and a critical approach to the statistics which, in final analysis, wants to replace epidemiology. It points out, moreover, that neglecting primary prevention as well as precautionary principles in the interpretation of public health studies, arises the suspicion of professional limitation or strong conflict of interests (business bias). Epidemiology is naturally oriented to both primary prevention and public health defense, and today, more than ever before, for many reasons, among which the overwhelming market power that is first and foremost the cause of the general increase of populations affected by avoidable pathologies, a systematic, correct and timely application of this precious discipline seems to be

ADenoVirus Initiative Study in Epidemiology (ADVISE): Results of a multicentric epidemiology study in Spain.

PubMed

Muñoz-Hernández, A M; Duquesroix, B; Benítez-Del-Castillo, J M

2018-03-01

Non-interventional, observational, epidemiology study to assess clinical characteristics and frequency of adenovirus conjunctivitis diagnosed by AdenoPlus ® in patients who presented with signs and symptoms of acute conjunctivitis. Safety aspects during use of the test were analyzed as well. This analysis presents the data obtained from the 386 patients enrolled in Spain. Patients had to present with acute signs and symptoms of conjunctivitis ≤7days. The minimum age was 1year old. Patients who had already used local antiviral therapies, topical steroids or immuno-modulators were not allowed to enter the study. A standardized questionnaire was used to collect patient's ocular history and test results. A total of 386 patients were recruited in 22 sites, being analyzed 329 patients. Among them, the percentage of "AdenoPlus ® positive" was 36,2% (119/329). Before the test was performed, in 84,1% of the cases, investigators believed that the conjunctivitis was of viral origin but only 50,3% of the investigators had their clinical assessment confirmed by the test. Patients who tested positive for adenoviral conjunctivitis presented higher percentages of signs and symptoms than the rest of the patients. None of the signs or symptoms could be qualified as pathognomonic of the disease, being difficult for the clinicians to perform an accurate diagnosis. AdenoPlus ® test is an antigen based immunoassay test that detects the presence of adenovirus directly from tears, and it can be an useful tool to help early differential diagnosis in patients with conjunctivitis signs and symptoms lasting for less than or equal to 7days. Copyright © 2017 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

Primary biliary cirrhosis: an epidemiological study.

PubMed Central

Triger, D R

1980-01-01

A three-year study (1977-9) of primary biliary cirrhosis in the city of Sheffield disclosed 34 cases, a point prevalence of 54 per million population. Closer inspection showed an apparent clustering of cases, and the prevalence in relation to one water reservoir appeared to be more than ten times that of the other reservoirs. Nevertheless, analyses of the water showed no significant relevant differences between the reservoir serving areas with a high prevalence of cirrhosis and other reservoirs. Despite the inconclusive results of the water analyses, these findings do suggest that an environmental agent may be a cause of primary biliary cirrhosis and that further epidemiological studies may help to elucidate the cause. PMID:7427444

Aspartame: a safety evaluation based on current use levels, regulations, and toxicological and epidemiological studies.

PubMed

Magnuson, B A; Burdock, G A; Doull, J; Kroes, R M; Marsh, G M; Pariza, M W; Spencer, P S; Waddell, W J; Walker, R; Williams, G M

2007-01-01

Aspartame is a methyl ester of a dipeptide used as a synthetic nonnutritive sweetener in over 90 countries worldwide in over 6000 products. The purpose of this investigation was to review the scientific literature on the absorption and metabolism, the current consumption levels worldwide, the toxicology, and recent epidemiological studies on aspartame. Current use levels of aspartame, even by high users in special subgroups, remains well below the U.S. Food and Drug Administration and European Food Safety Authority established acceptable daily intake levels of 50 and 40 mg/kg bw/day, respectively. Consumption of large doses of aspartame in a single bolus dose will have an effect on some biochemical parameters, including plasma amino acid levels and brain neurotransmitter levels. The rise in plasma levels of phenylalanine and aspartic acid following administration of aspartame at doses less than or equal to 50 mg/kg bw do not exceed those observed postprandially. Acute, subacute and chronic toxicity studies with aspartame, and its decomposition products, conducted in mice, rats, hamsters and dogs have consistently found no adverse effect of aspartame with doses up to at least 4000 mg/kg bw/day. Critical review of all carcinogenicity studies conducted on aspartame found no credible evidence that aspartame is carcinogenic. The data from the extensive investigations into the possibility of neurotoxic effects of aspartame, in general, do not support the hypothesis that aspartame in the human diet will affect nervous system function, learning or behavior. Epidemiological studies on aspartame include several case-control studies and one well-conducted prospective epidemiological study with a large cohort, in which the consumption of aspartame was measured. The studies provide no evidence to support an association between aspartame and cancer in any tissue. The weight of existing evidence is that aspartame is safe at current levels of consumption as a nonnutritive

The health impacts of semiconductor production: an epidemiologic review.

PubMed

Kim, Myoung-Hee; Kim, Hyunjoo; Paek, Domyung

2014-01-01

Despite concerns over the harmful health effects of semiconductor production, epidemiological studies have shown mixed results. We aim to critically appraise epidemiologic studies to date, and to suggest future research and actions to protect workers in semiconductor industry. Epidemiologic studies were identified through electronic database searches, review of reference lists of relevant published works, and expert consultations, and were narratively reviewed. Most evidence suggests reproductive risks from fabrication jobs, including spontaneous abortion (SAB), congenital malformation, and reduced fertility. Although chemicals have been suspected as causal agents, knowledge of the likely contribution(s) from specific exposures is still limited. Evidence of cancer risk seems to be equivocal. However, the available studies had serious limitations including healthy worker effects (HWEs), information bias, and insufficient power, all of which are associated with underestimation. Nevertheless, excess risks for non-Hodgkin's lymphoma (NHL), leukemia, brain tumor, and breast cancer were observed. Monitoring and innovative research based on international collaboration with a focus on sentinel events are required.

A method for meta-analysis of epidemiological studies.

PubMed

Einarson, T R; Leeder, J S; Koren, G

1988-10-01

This article presents a stepwise approach for conducting a meta-analysis of epidemiological studies based on proposed guidelines. This systematic method is recommended for practitioners evaluating epidemiological studies in the literature to arrive at an overall quantitative estimate of the impact of a treatment. Bendectin is used as an illustrative example. Meta-analysts should establish a priori the purpose of the analysis and a complete protocol. This protocol should be adhered to, and all steps performed should be recorded in detail. To aid in developing such a protocol, we present methods the researcher can use to perform each of 22 steps in six major areas. The illustrative meta-analysis confirmed previous traditional narrative literature reviews that Bendectin is not related to teratogenic outcomes in humans. The overall summary odds ratio was 1.01 (chi 2 = 0.05, p = 0.815) with a 95 percent confidence interval of 0.66-1.55. When the studies were separated according to study type, the summary odds ratio for cohort studies was 0.95 with a 95 percent confidence interval of 0.62-1.45. For case-control studies, the summary odds ratio was 1.27 with a 95 percent confidence interval of 0.83-1.94. The corresponding chi-square values were not statistically significant at the p = 0.05 level.

Can epidemiological studies discern subtle neurological effects due to perinatal exposure to PCBs?

PubMed

Seegal, R F

1996-01-01

exposed to contaminated aquatic and marine fish and mammals will allow investigators to determine which contaminant(s) may be responsible for the observed association between fish consumption and neurobehavioral deficits. For example, although PCB body burdens have been measured in the majority of the epidemiological studies, PCBs may simply reflect exposure to other fish-borne contaminants. In light of the above statements, future epidemiological studies should focus on highly exposed susceptible populations such as occupationally exposed workers or the aged. Results from these studies would provide important information on the risk of perinatal or adult exposure to PCBs in susceptible populations, although generalization of results obtained in these populations to the general population may be fraught with difficulties. Finally, because of the limitations of epidemiological studies, particularly those studying fish-eating populations, future risk assessments should depend more heavily on laboratory derived data, including studies in nonhuman primates exposed to environmentally relevant mixtures and relevant doses of PCB congeners and other known or suspected neurotoxicants.

Earth Observation, Spatial Data Quality, and Neglected Tropical Diseases.

PubMed

Hamm, Nicholas A S; Soares Magalhães, Ricardo J; Clements, Archie C A

2015-12-01

Earth observation (EO) is the use of remote sensing and in situ observations to gather data on the environment. It finds increasing application in the study of environmentally modulated neglected tropical diseases (NTDs). Obtaining and assuring the quality of the relevant spatially and temporally indexed EO data remain challenges. Our objective was to review the Earth observation products currently used in studies of NTD epidemiology and to discuss fundamental issues relating to spatial data quality (SDQ), which limit the utilization of EO and pose challenges for its more effective use. We searched Web of Science and PubMed for studies related to EO and echinococossis, leptospirosis, schistosomiasis, and soil-transmitted helminth infections. Relevant literature was also identified from the bibliographies of those papers. We found that extensive use is made of EO products in the study of NTD epidemiology; however, the quality of these products is usually given little explicit attention. We review key issues in SDQ concerning spatial and temporal scale, uncertainty, and the documentation and use of quality information. We give examples of how these issues may interact with uncertainty in NTD data to affect the output of an epidemiological analysis. We conclude that researchers should give careful attention to SDQ when designing NTD spatial-epidemiological studies. This should be used to inform uncertainty analysis in the epidemiological study. SDQ should be documented and made available to other researchers.

[John Snow, the cholera epidemic and the foundation of modern epidemiology].

PubMed

Cerda L, Jaime; Valdivia C, Gonzalo

2007-08-01

John Snow (1813-1858) was a brilliant British physician. Since young he stood out for his acute observation capacity, logical thinking and perseverance, first in anesthetics and later in epidemiology. The successive outbreaks of cholera that affected London, motivated him to study this disease from a populational point of view. He related the appearance of cases to the consumption of "morbid matter", responsible for the acute diarrhea with dehydration that characterizes this disease. Bravely, Snow opposed to certain theories present at his time, sacrificing his own prestige. He was a pioneer in the use of modern epidemiological investigation methodologies such as conducting surveys and spatial epidemiology. Fairly, he is considered nowadays as father of modern epidemiology by the scientific community.

Agent-Based vs. Equation-based Epidemiological Models:A Model Selection Case Study

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

Sukumar, Sreenivas R; Nutaro, James J

This paper is motivated by the need to design model validation strategies for epidemiological disease-spread models. We consider both agent-based and equation-based models of pandemic disease spread and study the nuances and complexities one has to consider from the perspective of model validation. For this purpose, we instantiate an equation based model and an agent based model of the 1918 Spanish flu and we leverage data published in the literature for our case- study. We present our observations from the perspective of each implementation and discuss the application of model-selection criteria to compare the risk in choosing one modeling paradigmmore » to another. We conclude with a discussion of our experience and document future ideas for a model validation framework.« less

[Prevalence of hearing impairment in northwestern Germany. Results of an epidemiological study on hearing status (HÖRSTAT)].

PubMed

von Gablenz, P; Holube, I

2015-03-01

A pure-tone average of 0.5, 1, 2, and 4 kHz in the better ear (PTA-4) is the international standard criterion set by the World Health Organization (WHO) to describe hearing loss. Presently, there are no epidemiological data on hearing loss in Germany based on this criterion. A representative sample of adults from Oldenburg and Emden were invited for a hearing assessment. This article analyzes the association between hearing loss and age, sex, noise, occupation, and educational level. Age- and sex-specific prevalence rates following the WHO classification are compared with international findings. According to the WHO classification, the prevalence of hearing impairment in the study cohort (n=1,866) is approx. 16%. In men, who more commonly work in noisy jobs, a higher prevalence rate is observed than in women of the same age. Nevertheless, sex differences in the present study are smaller than those reported in most international studies. PTA-4 is approximately the same for men and women when effects of occupational noise are controlled, but differences in prevalence between occupational areas are still significant. Compared with international findings, age-specific prevalence rates in HÖRSTAT are low. In the synopsis of epidemiological studies of the past 25 years, a trend toward decreasing prevalence in middle and higher age groups can be observed.

A systematic review about the epidemiology of primary progressive multiple sclerosis in Latin America and the Caribbean.

PubMed

Rojas, Juan Ignacio; Romano, Marina; Patrucco, Liliana; Cristiano, Edgardo

2018-02-24

Novel epidemiological data has appeared in recent years in Latin America (LATAM) regarding the epidemiology of multiple sclerosis (MS); however, most of this information is related to all MS subtypes, and no specific data was collected regarding the primary progressive form of MS (PPMS). The objective of this study was to perform an updated systematic review of the epidemiology of PPMS in LATAM. We conducted a systematic review of published epidemiological articles of PPMS from January 1997 to June 2017. No incidence data were found regarding PPMS. Differentiated prevalence was reported in 7 studies and ranged from 0.13 to 1.1 cases of PPMS per 100,000 inhabitants. Regarding subtype frequency, PPMS was observed in 10% of affected patients in proportional meta-analysis. No data about mortality were found. The study provides information on discriminated epidemiological features of PPMS in the region. The frequency observed was low in terms of prevalence. Follow up studies considering survival milestones and incidence data could provide a better understanding of the disease in the region. Copyright © 2018. Published by Elsevier B.V.

Toward systems epidemiology of coffee and health.

PubMed

Cornelis, Marilyn C

2015-02-01

Coffee is one of the most widely consumed beverages in the world and has been associated with many health conditions. This review examines the limitations of the classic epidemiological approach to studies of coffee and health, and describes the progress in systems epidemiology of coffee and its correlated constituent, caffeine. Implications and applications of this growing body of knowledge are also discussed. Population-based metabolomic studies of coffee replicate coffee-metabolite correlations observed in clinical settings but have also identified novel metabolites of coffee response, such as specific sphingomyelin derivatives and acylcarnitines. Genome-wide analyses of self-reported coffee and caffeine intake and serum levels of caffeine support an overwhelming role for caffeine in modulating the coffee consumption behavior. Interindividual variation in the physiological exposure or response to any of the many chemicals present in coffee may alter the persistence and magnitude of their effects. It is thus imperative that future studies of coffee and health account for this variation. Systems epidemiological approaches promise to inform causality, parse the constituents of coffee responsible for health effects, and identify the subgroups most likely to benefit from increasing or decreasing coffee consumption.

The utility of web mining for epidemiological research: studying the association between parity and cancer risk [Web Mining for Epidemiological Research. Assessing its Utility in Exploring the Association Between Parity and Cancer Risk

DOE PAGES

Tourassi, Georgia; Yoon, Hong-Jun; Xu, Songhua; ...

2015-11-27

Background: The World Wide Web has emerged as a powerful data source for epidemiological studies related to infectious disease surveillance. However, its potential for cancer-related epidemiological discoveries is largely unexplored. Methods: Using advanced web crawling and tailored information extraction procedures we automatically collected and analyzed the text content of 79,394 online obituary articles published between 1998 and 2014. The collected data included 51,911 cancer (27,330 breast; 9,470 lung; 6,496 pancreatic; 6,342 ovarian; 2,273 colon) and 27,483 non-cancer cases. With the derived information, we replicated a case-control study design to investigate the association between parity and cancer risk. Age-adjusted odds ratiosmore » (ORs) with 95% confidence intervals (CIs) were calculated for each cancer type and compared to those reported in large-scale epidemiological studies. Results: Parity was found to be associated with a significantly reduced risk of breast cancer (OR=0.78, 95% CI = 0.75 to 0.82), pancreatic cancer (OR=0.78, 95% CI = 0.72 to 0.83), colon cancer (OR=0.67, 95% CI = 0.60 to 0.74), and ovarian cancer (OR=0.58, 95% CI = 0.54 to 0.62). Marginal association was found for lung cancer prevalence (OR=0.87, 95% CI = 0.81 to 0.92). The linear trend between multi-parity and reduced cancer risk was dramatically more pronounced for breast and ovarian cancer than the other cancers included in the analysis. Conclusion: This large web-mining study on parity and cancer risk produced findings very similar to those reported with traditional observational studies. It may be used as a promising strategy to generate study hypotheses for guiding and prioritizing future epidemiological studies.« less

The utility of web mining for epidemiological research: studying the association between parity and cancer risk [Web Mining for Epidemiological Research. Assessing its Utility in Exploring the Association Between Parity and Cancer Risk

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

Tourassi, Georgia; Yoon, Hong-Jun; Xu, Songhua

Background: The World Wide Web has emerged as a powerful data source for epidemiological studies related to infectious disease surveillance. However, its potential for cancer-related epidemiological discoveries is largely unexplored. Methods: Using advanced web crawling and tailored information extraction procedures we automatically collected and analyzed the text content of 79,394 online obituary articles published between 1998 and 2014. The collected data included 51,911 cancer (27,330 breast; 9,470 lung; 6,496 pancreatic; 6,342 ovarian; 2,273 colon) and 27,483 non-cancer cases. With the derived information, we replicated a case-control study design to investigate the association between parity and cancer risk. Age-adjusted odds ratiosmore » (ORs) with 95% confidence intervals (CIs) were calculated for each cancer type and compared to those reported in large-scale epidemiological studies. Results: Parity was found to be associated with a significantly reduced risk of breast cancer (OR=0.78, 95% CI = 0.75 to 0.82), pancreatic cancer (OR=0.78, 95% CI = 0.72 to 0.83), colon cancer (OR=0.67, 95% CI = 0.60 to 0.74), and ovarian cancer (OR=0.58, 95% CI = 0.54 to 0.62). Marginal association was found for lung cancer prevalence (OR=0.87, 95% CI = 0.81 to 0.92). The linear trend between multi-parity and reduced cancer risk was dramatically more pronounced for breast and ovarian cancer than the other cancers included in the analysis. Conclusion: This large web-mining study on parity and cancer risk produced findings very similar to those reported with traditional observational studies. It may be used as a promising strategy to generate study hypotheses for guiding and prioritizing future epidemiological studies.« less

Evaluation of a rule-based method for epidemiological document classification towards the automation of systematic reviews.

PubMed

Karystianis, George; Thayer, Kristina; Wolfe, Mary; Tsafnat, Guy

2017-06-01

Most data extraction efforts in epidemiology are focused on obtaining targeted information from clinical trials. In contrast, limited research has been conducted on the identification of information from observational studies, a major source for human evidence in many fields, including environmental health. The recognition of key epidemiological information (e.g., exposures) through text mining techniques can assist in the automation of systematic reviews and other evidence summaries. We designed and applied a knowledge-driven, rule-based approach to identify targeted information (study design, participant population, exposure, outcome, confounding factors, and the country where the study was conducted) from abstracts of epidemiological studies included in several systematic reviews of environmental health exposures. The rules were based on common syntactical patterns observed in text and are thus not specific to any systematic review. To validate the general applicability of our approach, we compared the data extracted using our approach versus hand curation for 35 epidemiological study abstracts manually selected for inclusion in two systematic reviews. The returned F-score, precision, and recall ranged from 70% to 98%, 81% to 100%, and 54% to 97%, respectively. The highest precision was observed for exposure, outcome and population (100%) while recall was best for exposure and study design with 97% and 89%, respectively. The lowest recall was observed for the population (54%), which also had the lowest F-score (70%). The generated performance of our text-mining approach demonstrated encouraging results for the identification of targeted information from observational epidemiological study abstracts related to environmental exposures. We have demonstrated that rules based on generic syntactic patterns in one corpus can be applied to other observational study design by simple interchanging the dictionaries aiming to identify certain characteristics (i.e., outcomes

Dosimetric calculations for uranium miners for epidemiological studies.

PubMed

Marsh, J W; Blanchardon, E; Gregoratto, D; Hofmann, W; Karcher, K; Nosske, D; Tomásek, L

2012-05-01

Epidemiological studies on uranium miners are being carried out to quantify the risk of cancer based on organ dose calculations. Mathematical models have been applied to calculate the annual absorbed doses to regions of the lung, red bone marrow, liver, kidney and stomach for each individual miner arising from exposure to radon gas, radon progeny and long-lived radionuclides (LLR) present in the uranium ore dust and to external gamma radiation. The methodology and dosimetric models used to calculate these organ doses are described and the resulting doses for unit exposure to each source (radon gas, radon progeny and LLR) are presented. The results of dosimetric calculations for a typical German miner are also given. For this miner, the absorbed dose to the central regions of the lung is dominated by the dose arising from exposure to radon progeny, whereas the absorbed dose to the red bone marrow is dominated by the external gamma dose. The uncertainties in the absorbed dose to regions of the lung arising from unit exposure to radon progeny are also discussed. These dose estimates are being used in epidemiological studies of cancer in uranium miners.

Los Alamos National Laboratory: A guide to records series supporting epidemiologic studies conducted for the Department of Energy

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

NONE

1997-01-01

The purpose of this guide is to describe each series of records that pertains to the epidemiologic studies conducted by the Epidemiology Section of the Occupational Medicine Group (ESH-2) at the Department of Energy`s (DOE) Los Alamos National Laboratory (LANL) in Los Alamos, New Mexico. The records described in this guide relate to occupational studies performed by the Epidemiology Section, including those pertaining to workers at LANL, Mound Plant, Oak Ridge Reservation, Pantex Plant, Rocky Flats Plant, and Savannah River Site. Also included are descriptions of other health-related records generated or collected by the Epidemiology Section and a small setmore » of records collected by the Industrial Hygiene and Safety Group. This guide is not designed to describe the universe of records generated by LANL which may be used for epidemiologic studies of the LANL work force. History Associates Incorporated (HAI) prepared this guide as part of its work as the support services contractor for DOE`s Epidemiologic Records Inventory Project. This introduction briefly describes the Epidemiologic Records Inventory Project, HAI`s role in the project, the history of LANL the history and functions of LANL`s Health Division and Epidemiology Section, and the various epidemiologic studies performed by the Epidemiology Section. It provides information on the methodology that HAI used to inventory and describe records housed in the offices of the LANL Epidemiology Section in Technical Area 59 and at the LANL Records Center. Other topics include the methodology used to produce the guide, the arrangement of the detailed record series descriptions, and information concerning access to records repositories.« less

International Lymphoma Epidemiology Consortium

Cancer.gov

The InterLymph Consortium, or formally the International Consortium of Investigators Working on Non-Hodgkin's Lymphoma Epidemiologic Studies, is an open scientific forum for epidemiologic research in non-Hodgkin's lymphoma.

EPIDEMIOLOGIC CONCEPTS FOR INTERPRETING FINDINGS IN STUDIES OF DRINKING WATER EXPOSURES

EPA Science Inventory

To the inexperienced, environmental epidemiology may appear to be an uncomplicated, straightforward approach to studying exposure-disease associations in human populations. The studies can provide useful information about the risks of environmental exposures that human populatio...

[Epidemiologic and therapeutic study on gonorrheal infections--one shot therapy by aztreonam].

PubMed

Kumamoto, Y; Sakai, S; Tamate, H; Gohro, T; Inoke, T; Tabata, S; Tanda, H; Kato, S; Igawa, K; Tazuki, J

1985-11-01

A clinical study of a new monocyclic beta-lactam antibiotic, AZTREONAM (hereafter referred to as AZT) for gonorrheal infections as well as epidemiologic study of gonorrheal infections were made Epidemiology: There was a reflection of the increasing sexual activity of the younger generation; both male and female patients in their twenties were most frequent (male 49.5%, female 43.7%) and the percent of teen age patients was 15.1% (male) and 34.4% (female). Forty two strains (17.2%) out of 244 clinically isolated gonococci were PPNG. Residue of serious secretion was observed in a little less than 20% suggesting a complication by Chlamydia trachomatis. Clinical Result: One shot (1-2 g) therapy by AZT was given to 244 gonorrheal infection cases (212 urethritis cases of males. 32 cervicitis cases of females) with the following highly effective rate. Although beta-lactamase producing MIC of AZT at 10(6) CFU/ml showed a peak of 0.025 microgram/ml and ranged between less than 0.0125 microgram/ml to 0.2 microgram/ml. The time required for the elimination of gonococci was studied by the administration of 1 g and 2 g AZT. Gonococci became extinct in 1-8 hours or 4-4.5 hours on average. The difference between n 1 g and 2 g was scarcely observed. Clinical effect of 1 g one shot and 2 g one shot AZT was examined on the 3rd treatment day for 244 male and females cases. The effective rate was high; 90.7% by 1 g, 97.1% by 2 g for male urethritis, 100% by 1 g also by 2 g for female cervicitis. This therapeutic efficacy was kept even in PPNG, isolated cases. There were two side effects (0.8%), one case each of numbness and, redness and swelling of both hands, out of 244 cases, but both of them were minor ones without clinical complication.

The perfect food and the filth disease: milk-borne typhoid and epidemiological practice in late Victorian Britain.

PubMed

Steere-Williams, Jacob

2010-10-01

This article explores the initial set of epidemiological investigations in Victorian Britain that linked typhoid fever to milk from dairy cattle. Because Victorian epidemiologists first recognized the milk-borne route in outbreaks of typhoid fever, these investigations served as a model for later studies of milk-borne scarlet fever, diphtheria, and perhaps tuberculosis. By focusing on epidemiological practices conducted by Medical Inspectors at the Medical Department of the Local Government Board and Medical Officers of Health, I show that Victorian epidemiology was committed to field-based, observational methods that defined the professional nature of the discipline and its theories and practices. Epidemiological investigations of milk-borne typhoid heated up several important public health debates in the second half of the nineteenth century, and demonstrate how Victorian epidemiology was not solely wedded to examining population studies using statistical methods, as historians have typically argued, but also relied on observational case-tracing in individuals, animals, and even environments.

Epidemiological evidence in forensic pharmacovigilance.

PubMed

Persaud, Nav; Healy, David

2012-01-01

Until recently epidemiological evidence was not regarded as helpful in determining cause and effect. It generated associations that then had to be explained in terms of bio-mechanisms and applied to individual patients. A series of legal cases surrounding possible birth defects triggered by doxylamine (Bendectin) and connective tissue disorders linked to breast implants made it clear that in some instances epidemiological evidence might have a more important role, but the pendulum swung too far so that epidemiological evidence has in recent decades been given an unwarranted primacy, partly perhaps because it suits the interests of certain stakeholders. Older and more recent epidemiological studies on doxylamine and other antihistamines are reviewed to bring out the ambiguities and pitfalls of an undue reliance on epidemiological studies.

Development and application of Human Genome Epidemiology

NASA Astrophysics Data System (ADS)

Xu, Jingwen

2017-12-01

Epidemiology is a science that studies distribution of diseases and health in population and its influencing factors, it also studies how to prevent and cure disease and promote health strategies and measures. Epidemiology has developed rapidly in recent years and it is an intercross subject with various other disciplines to form a series of branch disciplines such as Genetic epidemiology, molecular epidemiology, drug epidemiology and tumor epidemiology. With the implementation and completion of Human Genome Project (HGP), Human Genome Epidemiology (HuGE) has emerged at this historic moment. In this review, the development of Human Genome Epidemiology, research content, the construction and structure of relevant network, research standards, as well as the existing results and problems are briefly outlined.

Epidemiology of endemic goitre in western Colombia

PubMed Central

Gaitan, E.; Merino, H.; Rodriguez, G.; Medina, P.; Meyer, J. D.; DeRouen, T. A.; MacLennan, R.

1978-01-01

This paper reports on recent epidemiological observations in western Colombia, which further demonstrate the presence of naturally-occurring goitrogens contaminating water supplies in areas where goitre persists despite prolonged and continuous iodine supplementation. 'Prospective' and 'cross-sectional' studies in 41 localities where the populations have been on a uniform and adequate iodine supplementation for the last 10-20 years indicate that, in the endemia of western Colombia, environmental factors other than nutritional iodine deficiency are responsible for differences in goitre prevalence. Further epidemiological studies to determine the causal factors for the persistence of the endemia established a correlation between the sources of drinking water and goitre prevalence rates. Organic compounds containing sulfur with marked thionamide-like antithyroid activity were isolated from water supplying endemic goitre districts, and results are presented supporting the hypothesis that sedimentary rocks rich in organic matter are the main source of water-borne goitrogens. Bacteriological investigations showed that the presence of Klebsiella pneumoniae in drinking water and bacterial concentration were related significantly with goitre prevalence only in the presence of other variables, particularly the presence of sedimentary rocks. In the light of these epidemiological observations and experimental studies it may be concluded that, at present, endemic goitre in western Colombia is not due to nutritional iodine deficiency, but that water supplies are contaminated with sulfur-bearing organic compounds with thionamide-like antithyroid activity most probably deriving from sedimentary rocks rich in organic matter and that these compounds are the main factor underlying the endemia. PMID:80287

TIME-INTEGRATED EXPOSURE MEASURES TO IMPROVE THE PREDICTIVE POWER OF EXPOSURE CLASSIFICATION FOR EPIDEMIOLOGIC STUDIES

EPA Science Inventory

Accurate exposure classification tools are required to link exposure with health effects in epidemiological studies. Although long-term integrated exposure measurements are a critical component of exposure assessment, the ability to include these measurements into epidemiologic...

The Current Status of the Disease Caused by Enterovirus 71 Infections: Epidemiology, Pathogenesis, Molecular Epidemiology, and Vaccine Development.

PubMed

Chang, Ping-Chin; Chen, Shou-Chien; Chen, Kow-Tong

2016-09-09

Enterovirus 71 (EV71) infections have a major public health impact in the Asia-Pacific region. We reviewed the epidemiology, pathogenesis, and molecular epidemiology of EV71 infection as well as EV71 vaccine development. Previous studies were found using the search terms "enterovirus 71" and "epidemiology" or "pathogenesis" or "molecular epidemiology" or "vaccine" in Medline and PubMed. Articles that were not published in the English language, manuscripts without an abstract, and opinion articles were excluded from the review. The reported epidemiology of cases caused by EV71 infection varied from country to country; seasonal variations in incidence were observed. Most cases of EV71 infection that resulted in hospitalization for complications occurred in children less than five years old. The brainstem was the most likely major target of EV71 infection. The emergence of the EV71 epidemic in the Asia-Pacific region has been associated with the circulation of different genetic lineages (genotypes B3, B4, C1, C2, and C4) that appear to be undergoing rapid evolutionary changes. The relationship between the gene structure of the EV71 virus and the factors that ensure its survival, circulation, and evasion of immunity is still unknown. EV71 infection has emerged as an important global public health problem. Vaccine development, including the development of inactivated whole-virus live attenuated, subviral particles, and DNA vaccines, has been progressing.

The impact of medicinal drugs on traffic safety: a systematic review of epidemiological studies.

PubMed

Orriols, Ludivine; Salmi, Louis-Rachid; Philip, Pierre; Moore, Nicholas; Delorme, Bernard; Castot, Anne; Lagarde, Emmanuel

2009-08-01

To evaluate the quality of epidemiological research into effects of medicinal drugs on traffic safety and the current knowledge in this area. The bibliographic search was done in Medline electronic database using the keywords: ((accident* or crash*) and traffic and drug*) leading to 1141 references. Additional references were retrieved from the Safetylit website and the reference lists of selected studies. Original articles published in English or French, between 1 April 1979 and 31 July 2008, were considered for inclusion. We excluded descriptive studies, studies limited to alcohol or illicit drug involvement and investigations of injuries other than from traffic crashes. Studies based on laboratory tests, driving simulators or on-the-road driving tests were also excluded. Eligible studies had to evaluate the causal relationship between the use of medicinal drugs and the risk of traffic crashes. Study quality was assessed by two independent experts, according to a grid adapted from the strengthening the reporting of observational studies in epidemiology (STROBE) statement. Twenty two studies of variable methodological quality were included. Definition of drug exposure varied across studies and depended on the data sources. Potential confounding due to the interaction between the effects of the medicinal drug and disease-related symptoms was often not controlled. The risk of motor-vehicle crashes related to benzodiazepines has been amply studied and demonstrated. Results for other medicinal drugs remain controversial. There is a need for large studies, investigating the role of individual substances in the risk of road traffic crashes. Copyright 2009 John Wiley & Sons, Ltd.

The Occurrence and Toxicity of Disinfection Byproducts in European Drinking Waters in Relation with the HIWATE Epidemiology Study

PubMed Central

Jeong, Clara H.; Wagner, Elizabeth D.; Siebert, Vincent R.; Anduri, Sridevi; Richardson, Susan D.; Daiber, Eric J.; McKague, A. Bruce; Kogevinas, Manolis; Villanueva, Cristina M.; Goslan, Emma H.; Luo, Wentai; Isabelle, Lorne M.; Pankow, James F.; Grazuleviciene, Regina; Cordier, Sylvaine; Edwards, Susan C.; Righi, Elena; Nieuwenhuijsen, Mark J.; Plewa, Michael J.

2012-01-01

The HIWATE (Health Impacts of long-term exposure to disinfection byproducts in drinking WATEr) project was a systematic analysis that combined the epidemiology on adverse pregnancy outcomes and other health effects with long term exposure to low levels of drinking water disinfection byproducts (DBPs) in the European Union. The present study focused on the relationship of the occurrence and concentration of DBPs with in vitro mammalian cell toxicity. Eleven drinking water samples were collected from 5 European countries. Each sampling location corresponded with an epidemiological study for the HIWATE program. Over 90 DBPs were identified; the range in the number of DBPs and their levels reflected the diverse collection sites, different disinfection processes, and the different characteristics of the source waters. For each sampling site, chronic mammalian cell cytotoxicity correlated highly with the numbers of DBPs identified and the levels of DBP chemical classes. Although there was a clear difference in the genotoxic responses among the drinking waters, these data did not correlate as well with the chemical analyses. Thus, the agents responsible for the genomic DNA damage observed in the HIWATE samples may be due to unresolved associations of combinations of identified DBPs, unknown emerging DBPs that were not identified, or other toxic water contaminants. This study represents the first to integrate quantitative in vitro toxicological data with analytical chemistry and human epidemiologic outcomes for drinking water DBPs. PMID:22958121

A Systematic Bayesian Integration of Epidemiological and Genetic Data

PubMed Central

Lau, Max S. Y.; Marion, Glenn; Streftaris, George; Gibson, Gavin

2015-01-01

Genetic sequence data on pathogens have great potential to inform inference of their transmission dynamics ultimately leading to better disease control. Where genetic change and disease transmission occur on comparable timescales additional information can be inferred via the joint analysis of such genetic sequence data and epidemiological observations based on clinical symptoms and diagnostic tests. Although recently introduced approaches represent substantial progress, for computational reasons they approximate genuine joint inference of disease dynamics and genetic change in the pathogen population, capturing partially the joint epidemiological-evolutionary dynamics. Improved methods are needed to fully integrate such genetic data with epidemiological observations, for achieving a more robust inference of the transmission tree and other key epidemiological parameters such as latent periods. Here, building on current literature, a novel Bayesian framework is proposed that infers simultaneously and explicitly the transmission tree and unobserved transmitted pathogen sequences. Our framework facilitates the use of realistic likelihood functions and enables systematic and genuine joint inference of the epidemiological-evolutionary process from partially observed outbreaks. Using simulated data it is shown that this approach is able to infer accurately joint epidemiological-evolutionary dynamics, even when pathogen sequences and epidemiological data are incomplete, and when sequences are available for only a fraction of exposures. These results also characterise and quantify the value of incomplete and partial sequence data, which has important implications for sampling design, and demonstrate the abilities of the introduced method to identify multiple clusters within an outbreak. The framework is used to analyse an outbreak of foot-and-mouth disease in the UK, enhancing current understanding of its transmission dynamics and evolutionary process. PMID:26599399

A one-year observational study of all hospitalized and fatal acute poisonings in Oslo: Epidemiology, intention and follow-up

PubMed Central

2012-01-01

Background Up to date information on poisoning trends is important. This study reports the epidemiology of all hospitalized acute poisonings in Oslo, including mortality, follow-up referrals, and whether the introduction of over-the-counter sales of paracetamol outside pharmacies had an impact on the frequency of poisonings. Methods All acute poisonings of adults (≥16 years) treated at the five hospitals in Oslo from April 2008 to April 2009 were included consecutively in an observational cross-sectional multicentre study. A standardized form was completed by the treating physician, which covered the study aims. All deaths by poisoning in and outside hospitals were registered at the Institute of Forensic Medicine. Results There were 1065 hospital admissions of 912 individuals; 460 (50%) were male, and the median age was 36 years. The annual incidence was 2.0 per 1000. The most frequent toxic agents were ethanol (18%), benzodiazepines (15%), paracetamol (11%), and opioids (11%). Physicians classified 46% as possible or definite suicide attempts, 37% as accidental overdoses with substances of abuse (AOSA), and 16% as other accidents. Twenty-four per cent were discharged without any follow-up and the no follow-up odds were highest for AOSA. There were 117 deaths (eight in hospital), of which 75% were males, and the median age was 41 years. Thus, the annual mortality rate was 25 per 100 000 and the in-hospital mortality was 0.8%. Opioids were the most frequent cause of death. Conclusions The incidence of hospitalized acute poisonings in Oslo was similar to that in 2003 and there was an equal sex distribution. Compared with a study performed in Oslo in 2003, there has been an increase in poisonings with a suicidal intention. The in-hospital mortality was low and nine out of ten deaths occurred outside hospitals. Opioids were the leading cause of death, so preventive measures should be encouraged among substance abusers. The number of poisonings caused by

Chlorine dioxide water disinfection: a prospective epidemiology study

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

Michael, G.E.; Miday, R.K.; Bercz, J.P.

An epidemiologic study of 198 persons exposed for 3 months to drinking water disinfected with chlorine dioxide was conducted in a rural village. A control population of 118 nonexposed persons was also studied. Pre-exposure hematologic and serum chemical parameters were compared with test results after 115 days of exposure. Chlorite ion levels in the water averaged approximately 5 ppM during the study period. Statistical analysis (ANOVA) of the data failed to identify any significant exposure-related effects. This study suggests that future evaluations of chlorine dioxide disinfection should be directed toward populations with potentially increased sensitivity to hemolytic agents.

The health impacts of semiconductor production: an epidemiologic review

PubMed Central

Kim, Myoung-Hee; Kim, Hyunjoo; Paek, Domyung

2014-01-01

Background: Despite concerns over the harmful health effects of semiconductor production, epidemiological studies have shown mixed results. Objectives: We aim to critically appraise epidemiologic studies to date, and to suggest future research and actions to protect workers in semiconductor industry. Methods: Epidemiologic studies were identified through electronic database searches, review of reference lists of relevant published works, and expert consultations, and were narratively reviewed. Results: Most evidence suggests reproductive risks from fabrication jobs, including spontaneous abortion (SAB), congenital malformation, and reduced fertility. Although chemicals have been suspected as causal agents, knowledge of the likely contribution(s) from specific exposures is still limited. Evidence of cancer risk seems to be equivocal. However, the available studies had serious limitations including healthy worker effects (HWEs), information bias, and insufficient power, all of which are associated with underestimation. Nevertheless, excess risks for non-Hodgkin's lymphoma (NHL), leukemia, brain tumor, and breast cancer were observed. Conclusions: Monitoring and innovative research based on international collaboration with a focus on sentinel events are required. PMID:24999845

Epidemiology of bacterial meningitis in the USA from 1997 to 2010: a population-based observational study.

PubMed

Castelblanco, Rodrigo Lopez; Lee, MinJae; Hasbun, Rodrigo

2014-09-01

Bacterial meningitis continues to be a substantial cause of morbidity and mortality, but the epidemiological trends after adjunctive dexamethasone recommendations are unknown in the USA. We aimed to describe the changing patterns among the most common bacterial causes in the USA after conjugate vaccination and to assess the association between adjunctive dexamethasone and mortality. For this population-based observational study, we searched information available from hospital discharges about incidence and inpatient mortality for the most important causes of community and nosocomial bacterial meningitis based on International Classification of Diseases coding across all hospitals in the USA between 1997 and 2010 with the HealthCare Cost Utilization Project (HCUP) network database. We calculated incidences according to US Census Bureau data and used a negative binomial regression model to evaluate the significance of changes over time. We assessed mortality from pneumococcus for three periods 1997-2001 (baseline), 2002-04 (transition years), and 2005-08 (after corticosteroid recommendations were available). Streptococcus pneumoniae incidence fell from 0·8 per 100 000 people in 1997, to 0·3 per 100 000 people by the end of 2010 (RR 0·3737, 95% CI 0·1825-0·7656). Mortality from pneumococcal meningitis decreased between 2005 (0·049 per 100 000 people) and 2008 (0·024 per 100 000 people) compared with between 2002 (0·073 per 100 000 people) and 2004 (0·063 per 100 000 people; RR 0·5720, 95% CI 0·4303-0·7582). The incidence of Neisseria meningitidis infection decreased from 0·721 per 100 000 people in 1997, to 0·123 per 100 000 people in 2010 (RR 0·1386, 95% CI 0·048-0·4284), which has placed this pathogen close to common bacterial causes of nosocomial meningitis such as staphylococcus and Gram-negative bacteria and to Haemophilus influenzae. S pneumoniae continues to be the leading identifiable cause of bacterial meningitis in the USA

Intricacies of assessing the human microbiome in epidemiological studies

PubMed Central

Robinson, Courtney K.; Brotman, Rebecca M.; Ravel, Jacques

2016-01-01

Purpose In the past decade, remarkable relationships have been documented between dysbiosis of the human microbiota and adverse health outcomes. This review seeks to highlight some of the challenges and pitfalls that may be encountered during all stages of microbiota research, from study design and sample collection, to nucleic acid extraction and sequencing, and bioinformatic and statistical analysis. Methods Literature focused on human microbiota research was reviewed and summarized. Results While most studies have focused on surveying the composition of the microbiota, fewer have explored the causal roles of these bacteria, archaea, viruses, and fungi in affecting disease states. Microbiome research is in its relatively early years and many aspects remain challenging, including the complexity and personalized aspects of microbial communities, the influence of exogenous and often confounding factors, the need to apply fundamental principles of ecology and epidemiology, the necessity for new software tools, and the rapidly evolving genomic, technological, and analytical landscapes. Conclusions Incorporating human microbiome research in large epidemiological studies will soon help us unravel the intricate relationships that we have with our microbial partners and provide interventional opportunities to improve human health. PMID:27180112

Photon-Fluence-Weighted let for Radiation Fields Subjected to Epidemiological Studies.

PubMed

Sasaki, Michiya

2017-08-01

In order to estimate the uncertainty of the radiation risk associated with the photon energy in epidemiological studies, photon-fluence-weighted LET values were quantified for photon radiation fields with the target organs and irradiation conditions taken into consideration. The photon fluences giving a unit absorbed dose to the target organ were estimated by using photon energy spectra together with the dose conversion coefficients given in ICRP Publication 116 for the target organs of the colon, bone marrow, stomach, lung, skin and breast with three irradiation geometries. As a result, it was demonstrated that the weighted LET values did not show a clear difference among the photon radiation fields subjected to epidemiological studies, regardless of the target organ and the irradiation geometry.

Epidemiology: Then and Now.

PubMed

Kuller, Lewis H

2016-03-01

Twenty-five years ago, on the 75th anniversary of the Johns Hopkins Bloomberg School of Public Health, I noted that epidemiologic research was moving away from the traditional approaches used to investigate "epidemics" and their close relationship with preventive medicine. Twenty-five years later, the role of epidemiology as an important contribution to human population research, preventive medicine, and public health is under substantial pressure because of the emphasis on "big data," phenomenology, and personalized medical therapies. Epidemiology is the study of epidemics. The primary role of epidemiology is to identify the epidemics and parameters of interest of host, agent, and environment and to generate and test hypotheses in search of causal pathways. Almost all diseases have a specific distribution in relation to time, place, and person and specific "causes" with high effect sizes. Epidemiology then uses such information to develop interventions and test (through clinical trials and natural experiments) their efficacy and effectiveness. Epidemiology is dependent on new technologies to evaluate improved measurements of host (genomics), epigenetics, identification of agents (metabolomics, proteomics), new technology to evaluate both physical and social environment, and modern methods of data collection. Epidemiology does poorly in studying anything other than epidemics and collections of numerators and denominators without specific hypotheses even with improved statistical methodologies. © The Author 2015. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The justification of studies in genetic epidemiology - political scaling in China Medical City.

PubMed

Sleeboom-Faulkner, Margaret

2018-04-01

Genetic epidemiology examines the role of genetic factors in determining health and disease in families and in populations to help addressing health problems in a responsible manner. This paper uses a case study of genetic epidemiology in Taizhou, China, to explore ways in which anthropology can contribute to the validation of studies in genetic epidemiology. It does so, first, by identifying potential overgeneralizations of data, often due to mismatching scale and, second, by examining it's embedding in political, historical and local contexts. The example of the longitudinal cohort study in Taizhou illustrates dimensions of such 'political scaling'. Political scaling is a notion used here to refer to the effects of scaling biases in relation to the justification of research in terms of relevance, reach and research ethics. The justification of a project on genetic epidemiology involves presenting a maximum of benefits and a minimum of burden for the population. To facilitate the delineation of political scaling, an analytical distinction between donating and benefiting communities was made using the notions of 'scaling of relevance', 'scaling of reach' and 'scaling of ethics'. Political scaling results at least partly from factors external to research. By situating political scaling in the context of historical, political and local discourses, anthropologists can play a complementary role in genetic epidemiology.

Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

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

Fabrikant, J.I.

1982-08-01

The present review provides an understanding of our current knowledge of the carcinogenic effect of low-dose radiation in man, and surveys the epidemiological studies of human populations exposed to nuclear explosions and medical radiation. Discussion centers on the contributions of quantitative epidemiology to present knowledge, the reliability of the dose-incidence data, and those relevant epidemiological studies that provide the most useful information for risk estimation of cancer-induction in man. Reference is made to dose-incidence relationships from laboratory animal experiments where they may obtain for problems and difficulties in extrapolation from data obtained at high doses to low doses, and frommore » animal data to the human situation. The paper describes the methods of application of such epidemiological data for estimation of excess risk of radiation-induced cancer in exposed human populations, and discusses the strengths and limitations of epidemiology in guiding radiation protection philosophy and public health policy.« less

Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation.

PubMed Central

Fabrikant, J. I.

1981-01-01

The present review provides an understanding of our current knowledge of the carcinogenic effect of low-dose radiation in man, and surveys the epidemiological studies of human populations exposed to nuclear explosions and medical radiation. Discussion centers on the contributions of quantitative epidemiology to present knowledge, the reliability of the dose-incidence data, and those relevant epidemiological studies that provide the most useful information for risk estimation of cancer induction in man. Reference is made to dose-incidence relationships from laboratory animal experiments where they may obtain, for problems and difficulties in extrapolation from data obtained at high doses to low doses, and from animal data to the human situation. The paper describes the methods of application of such epidemiological data for estimation of excess risk of radiation-induced cancer in exposed human populations and discusses the strengths and limitations of epidemiology in guiding radiation protection philosophy and public health policy. PMID:7043913

Performance of gout definitions for genetic epidemiological studies: analysis of UK Biobank.

PubMed

Cadzow, Murray; Merriman, Tony R; Dalbeth, Nicola

2017-08-09

Many different combinations of available data have been used to identify gout cases in large genetic studies. The aim of this study was to determine the performance of case definitions of gout using the limited items available in multipurpose cohorts for population-based genetic studies. This research was conducted using the UK Biobank Resource. Data, including genome-wide genotypes, were available for 105,421 European participants aged 40-69 years without kidney disease. Gout definitions and combinations of these definitions were identified from previous epidemiological studies. These definitions were tested for association with 30 urate-associated single-nucleotide polymorphisms (SNPs) by logistic regression, adjusted for age, sex, waist circumference, and ratio of waist circumference to height. Heritability estimates under an additive model were generated using GCTA version 1.26.0 and PLINK version 1.90b3.32 by partitioning the genome. There were 2066 (1.96%) cases defined by self-report of gout, 1652 (1.57%) defined by urate-lowering therapy (ULT) use, 382 (0.36%) defined by hospital diagnosis, 1861 (1.76%) defined by hospital diagnosis or gout-specific medications and 2295 (2.18%) defined by self-report of gout or ULT use. Association with gout at experiment-wide significance (P < 0.0017) was observed for 13 SNPs with gout using the self-report of gout or ULT use definition, 12 SNPs using the self-report of gout definition, 11 SNPs using the hospital diagnosis or gout-specific medication definition, 10 SNPs using ULT use definition and 3 SNPs using hospital diagnosis definition. Heritability estimates ranged from 0.282 to 0.308 for all definitions except hospital diagnosis (0.236). Of the limited items available in multipurpose cohorts, the case definition of self-report of gout or ULT use has high sensitivity and precision for detecting association in genetic epidemiological studies of gout.

Epidemiology study at a South Carolina Beach impacted by stormwater runoff

EPA Science Inventory

EPA conducted an epidemiological study in the summer of 2009. Among the selection criteria for the study location was that beach water quality was affected primarily by stormwater runoff. Preliminary findings from the summer's research will be presented. This abstract does not ne...

The emergence of translational epidemiology: from scientific discovery to population health impact.

PubMed

Khoury, Muin J; Gwinn, Marta; Ioannidis, John P A

2010-09-01

Recent emphasis on translational research (TR) is highlighting the role of epidemiology in translating scientific discoveries into population health impact. The authors present applications of epidemiology in TR through 4 phases designated T1-T4, illustrated by examples from human genomics. In T1, epidemiology explores the role of a basic scientific discovery (e.g., a disease risk factor or biomarker) in developing a "candidate application" for use in practice (e.g., a test used to guide interventions). In T2, epidemiology can help to evaluate the efficacy of a candidate application by using observational studies and randomized controlled trials. In T3, epidemiology can help to assess facilitators and barriers for uptake and implementation of candidate applications in practice. In T4, epidemiology can help to assess the impact of using candidate applications on population health outcomes. Epidemiology also has a leading role in knowledge synthesis, especially using quantitative methods (e.g., meta-analysis). To explore the emergence of TR in epidemiology, the authors compared articles published in selected issues of the Journal in 1999 and 2009. The proportion of articles identified as translational doubled from 16% (11/69) in 1999 to 33% (22/66) in 2009 (P = 0.02). Epidemiology is increasingly recognized as an important component of TR. By quantifying and integrating knowledge across disciplines, epidemiology provides crucial methods and tools for TR.

The Emergence of Translational Epidemiology: From Scientific Discovery to Population Health Impact

PubMed Central

Khoury, Muin J.; Gwinn, Marta; Ioannidis, John P. A.

2010-01-01

Recent emphasis on translational research (TR) is highlighting the role of epidemiology in translating scientific discoveries into population health impact. The authors present applications of epidemiology in TR through 4 phases designated T1–T4, illustrated by examples from human genomics. In T1, epidemiology explores the role of a basic scientific discovery (e.g., a disease risk factor or biomarker) in developing a “candidate application” for use in practice (e.g., a test used to guide interventions). In T2, epidemiology can help to evaluate the efficacy of a candidate application by using observational studies and randomized controlled trials. In T3, epidemiology can help to assess facilitators and barriers for uptake and implementation of candidate applications in practice. In T4, epidemiology can help to assess the impact of using candidate applications on population health outcomes. Epidemiology also has a leading role in knowledge synthesis, especially using quantitative methods (e.g., meta-analysis). To explore the emergence of TR in epidemiology, the authors compared articles published in selected issues of the Journal in 1999 and 2009. The proportion of articles identified as translational doubled from 16% (11/69) in 1999 to 33% (22/66) in 2009 (P = 0.02). Epidemiology is increasingly recognized as an important component of TR. By quantifying and integrating knowledge across disciplines, epidemiology provides crucial methods and tools for TR. PMID:20688899

Epidemiology in Germany-general development and personal experience.

PubMed

Wichmann, Heinz-Erich

2017-08-01

Did you ever hear about epidemiology in Germany? Starting from an epidemiological desert the discipline has grown remarkably, especially during the last 10-15 years: research institutes have been established, research funding has improved, multiple curriculae in Epidemiology and Public Health are offered. This increase has been quite steep, and now the epidemiological infrastructure is much better. Several medium-sized and even big population cohorts are ongoing, and the number and quality of publications from German epidemiologists has reached a respectable level. My own career in epidemiology started in the field of environmental health. After German reunification I concentrated for many years on environmental problems in East Germany and observed the health benefits after improvement of the situation. Later, I concentrated on population-based cohorts in newborns (GINI/LISA) and adults (KORA, German National Cohort), and on biobanking. This Essay describes the development in Germany after worldwar 2, illustrated by examples of research results and build-up of epidemiological infractructures worth mentioning.

Soy intake is associated with lower lung cancer risk: results from a meta-analysis of epidemiologic studies123

PubMed Central

Yang, Wan-Shui; Va, Puthiery; Wong, Man-Yu; Zhang, Huan-Ling

2011-01-01

Background: Although several in vitro and animal in vivo studies have suggested that soy or soy isoflavones may exert inhibitory effects on lung carcinogenesis, epidemiologic studies have reported inconclusive results on the association between soy intake and lung cancer. Objective: The aim of this meta-analysis was to investigate whether an association exists between soy and lung cancer in epidemiologic studies. Design: We searched PubMed, EMBASE, and the Cochrane Library from their inception to February 2011 for both case-control and cohort studies that assessed soy consumption and lung cancer risk. Study-specific risk estimates were combined by using fixed-effect or random-effect models. Results: A total of 11 epidemiologic studies that consisted of 8 case-control and 3 prospective cohort studies were included. A significantly inverse association was shown between soy intake and lung cancer with an overall RR of 0.77 (95% CI: 0.65, 0.92). Findings were slightly different when analyses were restricted to 5 high-quality studies (RR: 0.70; 95% CI: 0.45, 0.99). In a subgroup meta-analysis, a statistically significant protective effect of soy consumption was observed in women (RR: 0.79; 95% CI: 0.67, 0.93), never smokers (RR: 0.62; 95% CI: 0.51, 0.76), and Asian populations (RR: 0.86; 95% CI: 0.74, 0.98). Conclusions: Our findings indicate that the consumption of soy food is associated with lower lung cancer risk. Because of different methods used to assess soy consumption across studies, more well-designed cohort studies or intervention studies that use unified measures of soy intake are needed to fully characterize such an association. PMID:22071712

Air Pollution Exposure Modeling for Epidemiology Studies and Public Health

EPA Science Inventory

Air pollution epidemiology studies of ambient fine particulate matter (PM2.5) often use outdoor concentrations as exposure surrogates. These surrogates can induce exposure error since they do not account for (1) time spent indoors with ambient PM2.5 levels attenuated from outdoor...

Molecular and epidemiological study of enterovirus D68 in Taiwan.

PubMed

Huang, Yuan-Pin; Lin, Tsuey-Li; Lin, Ting-Han; Wu, Ho-Sheng

2017-08-01

As an immunofluorescence assay for enterovirus D68 (EV-D68) is not available in the enteroviruses surveillance network in Taiwan, EV-D68 may be the actual pathogen of untypeable enterovirus-suspected isolates. The untypeable isolates collected from 2007 through 2014 were identified by nucleic acid amplification-based methods and sequencing of the VP1 region to analyze the phylogeny and epidemiology of EV-D68 in Taiwan. Twenty-nine EV-D68 isolates were sequenced, including 15 Cluster 3 and 14 Cluster 1 viruses. Approximately 41% of the patients were children under 5 years of age and their infections peaked in August. The ratio of male to female patients was 1.5 and 3.67 for Cluster 3 and Cluster 1, respectively. Fever and respiratory symptoms were commonly reported in EV-D68-infected patients. The results of phylogenetic analyses showed that EV-D68 isolates between 2007 and 2014 belonged to different clusters and existed for years, indicating that endemic circulation of EV-D68 existed in Taiwan. This study showed that EV-D68 has been endemic in Taiwan for some years despite a small number of positive cases. The continuous monitoring and efforts towards the improvement of diagnostic techniques are required to complete the surveillance system. This study provided the genetic and epidemiological information which could contribute to understanding the etiology and epidemiology of EV-D68. Copyright © 2015. Published by Elsevier B.V.

Mental Subnormality in the Community: A Clinical and Epidemiologic Study.

ERIC Educational Resources Information Center

Birch, Herbert G.; And Others

The book reports a clinical and epidemiologic study of the prevalence, distribution, and antecedents of mental subnormality in 8 to 10 year old children living in Aberdeen, Scotland (population 187,000). Utilizing three types of data (differential clinical diagnoses, biological background information, and social characteristics), the study…

Research Methods in Healthcare Epidemiology and Antimicrobial Stewardship-Mathematical Modeling.

PubMed

Barnes, Sean L; Kasaie, Parastu; Anderson, Deverick J; Rubin, Michael

2016-11-01

Mathematical modeling is a valuable methodology used to study healthcare epidemiology and antimicrobial stewardship, particularly when more traditional study approaches are infeasible, unethical, costly, or time consuming. We focus on 2 of the most common types of mathematical modeling, namely compartmental modeling and agent-based modeling, which provide important advantages-such as shorter developmental timelines and opportunities for extensive experimentation-over observational and experimental approaches. We summarize these advantages and disadvantages via specific examples and highlight recent advances in the methodology. A checklist is provided to serve as a guideline in the development of mathematical models in healthcare epidemiology and antimicrobial stewardship. Infect Control Hosp Epidemiol 2016;1-7.

Turkey’s Epidemiological and Demographic Transitions: 1931-2013

PubMed Central

Bakar, Coşkun; Oymak, Sibel; Maral, Işıl

2017-01-01

Background: The causes of death have changed with regard to the epidemiological and demographic events in society. There is no evidence of prior research into the epidemiological transition in Turkey. This transition in Turkey should be observed starting with the Ottoman Empire period (19th to early 20th century). However, information about the Ottoman Empire is quite limited. Aims: To discuss the epidemiological and demographic transitions in Turkey, using demographic, educational and urbanization data in our present study. Study Design: A descriptive archive study. Methods: Mortality statistics dating from 1931 and published by the Turkish Statistical Institute were analysed, and the causes of death were coded and classified according to ICD-10. Other data were obtained from the published reports and studies regarding the issue. Results: In the 1930s, Turkey’s life expectancy was low (aged 40 years), fertility and mortality rates were high (respectively 45% and 31%), and the main causes of death were infectious diseases. Nowadays, life expectancy is close to 80 years, the total fertility rate has dropped to 2.1 per woman, and the main causes of death are chronic diseases and cancer. The population rate in the urban areas has increased steadily from 24.2% in 1927 to 77.3% in 2012. level of education has also increased during this period. In 1935, less than 10% of women were literate, and in 2013 90% were literate. Qualitative and quantitative increase have been observed in the presentation and access of healthcare services compared to the early years of the Republic. Conclusion: Turkey has been undergoing a modernization period in the last 200 years, and it is believed that the epidemiological and demographic transitions result from this period. This process has led to urbanization and an increase in the level of education, as well as a decrease in premature deaths, lower fertility rates, and an increase in the elderly population and chronic diseases. It is

Epidemiology and causation: a realist view.

PubMed Central

Renton, A

1994-01-01

In this paper the controversy over how to decide whether associations between factors and diseases are causal is placed within a description of the public health and scientific relevance of epidemiology. It is argued that the rise in popularity of the Popperian view of science, together with a perception of the aims of epidemiology as being to identify appropriate public health interventions, have focussed this debate on unresolved questions of inferential logic, leaving largely unanalysed the notions of causation and of disease at the ontological level. A realist ontology of causation of disease and pathogenesis is constructed within the framework of "scientific materialism", and is shown to provide a coherent basis from which to decide causes and to deal with problems of confounding and interaction in epidemiological research. It is argued that a realist analysis identifies a richer role for epidemiology as an integral part of an ontologically unified medical science. It is this unified medical science as a whole rather than epidemiological observation or experiment which decides causes and, in turn, provides a key element to the foundations of rational public health decision making. PMID:8138775

Hyper-insulinaemia and cancer, meta-analyses of epidemiological studies.

PubMed

Pisani, Paola

2008-02-01

A substantial body of evidence links sex hormones, diet, excess body weight and physical activity to the risk of developing cancer at several sites common in affluent countries. The hypothesis that high circulating levels of insulin could be the underlying factor increasing cancer risk has been proposed. Epidemiological studies on markers of hyper-insulinaemia and cancer are reviewed and summarized. Studies of cancers of the colon and rectum, pancreas, breast, and endometrium examining the association with blood levels of C-peptide, insulin, glucose, glycated haemoglobin (HbA1c) were searched in PubMed. Multivariate, adjusted relative risks (RR) and their 95% confidence intervals were abstracted and summarized by meta-analyses. Most of the studies identified were cohorts that relied on measurements obtained at baseline or assessed in blood stored at low temperature several years before the onset of cancer. The meta-analyses showed excess risks of colorectal and pancreatic cancers associated with higher levels of circulating C-peptide/insulin and with markers of glycaemia. Significant heterogeneity was found among four epidemiological studies of endometrial cancer and C-peptide giving a summary RR compatible with no association. Overall breast cancer risk was significantly higher in the upper categories of C-peptide/insulin, however, the excess derived entirely from retrospective studies. Current evidence suggests that subjects who develop colorectal and pancreatic cancers have increased pre-diagnostic blood levels of insulin and glucose.

The Use of Satellite Remote Sensing in Epidemiological Studies

PubMed Central

Sorek-Hamer, Meytar; Just, Allan C.; Kloog, Itai

2016-01-01

Purpose of review Particulate matter (PM) air pollution is a ubiquitous exposure linked with multiple adverse health outcomes for children and across the life course. The recent development of satellite based remote sensing models for air pollution enables the quantification of these risks and addresses many limitations of previous air pollution research strategies. We review the recent literature on the applications of satellite remote sensing in air quality research, with a focus on their use in epidemiological studies. Recent findings Aerosol optical depth (AOD) is a focus of this review and a significant number of studies show that ground-level PM can be estimated from columnar AOD. Satellite measurements have been found to be an important source of data for PM model-based exposure estimates, and recently have been used in health studies to increase the spatial breadth and temporal resolution of these estimates. Summary It is suggested that satellite-based models improve our understanding of the spatial characteristics of air quality. Although the adoption of satellite-based measures of air quality in health studies is in its infancy, it is rapidly growing. Nevertheless, further investigation is still needed in order to have a better understanding of the AOD contribution to these prediction models in order to use them with higher accuracy in epidemiological studies. PMID:26859287

Advances in satellite remote sensing of environmental variables for epidemiological applications.

PubMed

Goetz, S J; Prince, S D; Small, J

2000-01-01

Earth-observing satellites have provided an unprecedented view of the land surface but have been exploited relatively little for the measurement of environmental variables of particular relevance to epidemiology. Recent advances in techniques to recover continuous fields of air temperature, humidity, and vapour pressure deficit from remotely sensed observations have significant potential for disease vector monitoring and related epidemiological applications. We report on the development of techniques to map environmental variables with relevance to the prediction of the relative abundance of disease vectors and intermediate hosts. Improvements to current methods of obtaining information on vegetation properties, canopy and surface temperature and soil moisture over large areas are also discussed. Algorithms used to measure these variables incorporate visible, near-infrared and thermal infrared radiation observations derived from time series of satellite-based sensors, focused here primarily but not exclusively on the Advanced Very High Resolution Radiometer (AVHRR) instruments. The variables compare favourably with surface measurements over a broad array of conditions at several study sites, and maps of retrieved variables captured patterns of spatial variability comparable to, and locally more accurate than, spatially interpolated meteorological observations. Application of multi-temporal maps of these variables are discussed in relation to current epidemiological research on the distribution and abundance of some common disease vectors.

Assessing exposure in epidemiologic studies to disinfection by-products in drinking water: report from an international workshop.

PubMed Central

Arbuckle, Tye E; Hrudey, Steve E; Krasner, Stuart W; Nuckols, Jay R; Richardson, Susan D; Singer, Philip; Mendola, Pauline; Dodds, Linda; Weisel, Clifford; Ashley, David L; Froese, Kenneth L; Pegram, Rex A; Schultz, Irvin R; Reif, John; Bachand, Annette M; Benoit, Frank M; Lynberg, Michele; Poole, Charles; Waller, Kirsten

2002-01-01

The inability to accurately assess exposure has been one of the major shortcomings of epidemiologic studies of disinfection by-products (DBPs) in drinking water. A number of contributing factors include a) limited information on the identity, occurrence, toxicity, and pharmacokinetics of the many DBPs that can be formed from chlorine, chloramine, ozone, and chlorine dioxide disinfection; b) the complex chemical interrelationships between DBPs and other parameters within a municipal water distribution system; and c) difficulties obtaining accurate and reliable information on personal activity and water consumption patterns. In May 2000, an international workshop was held to bring together various disciplines to develop better approaches for measuring DBP exposure for epidemiologic studies. The workshop reached consensus about the clear need to involve relevant disciplines (e.g., chemists, engineers, toxicologists, biostatisticians and epidemiologists) as partners in developing epidemiologic studies of DBPs in drinking water. The workshop concluded that greater collaboration of epidemiologists with water utilities and regulators should be encouraged in order to make regulatory monitoring data more useful for epidemiologic studies. Similarly, exposure classification categories in epidemiologic studies should be chosen to make results useful for regulatory or policy decision making. PMID:11834463

Uses of available record systems in epidemiologic studies of reproductive toxicology

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

Polednak, A.P.; Janerich, D.T.

The uses of available record systems in epidemiologic studies of reproductive toxicology are described with reference to New York State. The available record systems (and relevant reproductive end points) described include: a newborn screening program for metabolic diseases and hemoglobinopathies (relevant to point mutations); chromosome registries and prenatal cytogenetics (for chromosome anomalies); live birth certificates (for birth defects, birthweight, sex ratio, etc); fetal death certificates (for spontaneous fetal deaths); and a statewide cancer registry (for childhood cancers and transplacental carcinogenesis). The uses and limitations of these record systems are discussed, along with examples of their use in descriptive and analyticmore » epidemiologic studies. Descriptive studies outlined include investigations of temporal and geographic trends in birth defects, birth weight, and fetal deaths, with reference to environmental questions (eg, Love Canal, nuclear power plants). Analytic studies described concern parental occupation in relation to specific birth defects (neural tube defects and Down syndrome) and maternal use of contraceptive drugs.« less

Injuries and other adverse events associated with yoga practice: A systematic review of epidemiological studies.

PubMed

Cramer, Holger; Ostermann, Thomas; Dobos, Gustav

2018-02-01

To systematically assess the prevalence of yoga-associated injuries and other adverse events in epidemiological studies. Systematic review of observational studies. Medline/PubMed, Scopus, the Cochrane Library, and IndMed were searched through October 2016 for epidemiological studies assessing the prevalence of adverse events of yoga practice or comparing the risk of any adverse events between yoga practitioners and non-yoga practitioners. Nine observational studies with a total 9129 yoga practitioners and 9903 non-yoga practitioners were included. Incidence proportion of adverse events during a yoga class was 22.7% (95% confidence interval [CI]=21.1%-24.3%); 12-months prevalence was 4.6% (95%CI=3.8%-5.4%), and lifetime prevalence ranged from 21.3% (95%CI=19.7%-22.9%) to 61.8% (95%CI=52.8%-70.8%) of yoga practitioners. Serious adverse events occurred in 1.9% (95%CI=1.4%-2.4%). The most common adverse events related to the musculoskeletal system; the most common injuries were sprains and strains. Compared to non-yoga practitioners, yoga practitioners had a comparable risk of falls (odds ratio [OR]=0.90; 95%CI=0.76-1.08), and falls-related injuries (OR=1.04; 95%CI=0.83-1.29), and higher risk of meniscus injuries (OR=1.72; 95%CI=1.23-2.41). A considerable proportion of yoga practitioners experienced injuries or other adverse events; however most were mild and transient and risks were comparable to those of non-yoga practitioners. There is no need to discourage yoga practice for healthy people. People with serious acute or chronic illnesses should seek medical advice before practicing yoga. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Epidemiologic methods in mastitis treatment and control.

PubMed

Thurmond, M C

1993-11-01

Methods and concepts of epidemiology offer means whereby udder health can be monitored and evaluated. Prerequisite to a sound epidemiologic approach is development of measures of mastitis that minimize biases and that account for sensitivity and specificity of diagnostic tests. Mastitis surveillance offers an ongoing and passive system for evaluation of udder health, whereas clinical and observational trials offer a more proactive and developmental approach to improving udder health.

Air pollution exposure prediction approaches used in air pollution epidemiology studies

EPA Science Inventory

Epidemiological studies of the health effects of air pollution have traditionally relied upon surrogates of personal exposures, most commonly ambient concentration measurements from central-site monitors. However, this approach may introduce exposure prediction errors and miscla...

[Epidemiology and Public Health: tendencies of the Brazilian epidemiology production regarding volume, indexation and investigation areas - 2001 to 2006].

PubMed

Turci, Silvana Rubano Barretto; Guilam, Maria Cristina Rodrigues; Câmara, Maria Clara Coelho

2010-07-01

This article examines and interprets the trends of epidemiological production in Brazil in the Public Health context. CAPES indicators from 2001 to 2006 were used as database. We analyzed 26 programs and select the 10 major ones to analyze their bibliographic production in indexed journals. It was observed that the total production of epidemiological articles accounted for 40% of production in Public Health and 55% of the production was published in international journals, especially Cadernos de Saúde Pública, Revista de Saúde Pública and Ciência & Saúde Coletiva. The most prevalent themes were public health nutrition, maternal and infant health and, infectious diseases, particularly AIDS. Environmental e worker's heath, oral health, violence and health of the elderly have been ratified as objects of study for the discipline, while meta-analysis and geoprocessing appear as a useful tool for health services. We conclude that the epidemiological production tends to increase in indexed publications, covering various topics and a wide spectrum of relevant issues to Brazilian health policy.

[Work, schooling, and reproductive health: an ethno-epidemiological study of adolescent women belonging to a birth cohort].

PubMed

Gonçalves, Helen; Gigante, Denise

2006-07-01

An ethno-epidemiological study was carried out with adolescent women who have been studied since birth. In 2001, all female adolescents from the 1982 Pelotas Birth Cohort were identified in 27% of all census tracts in Pelotas, Rio Grande do Sul State. Risk factors for childbearing during adolescence were investigated using a case-control approach. Cases (n = 420) were identified through the local live birth information system, and controls included 408 women who had not given birth by 2001. To understand social and cultural factors related to childbearing during adolescence, an ethnographic study focused on 23 young women from the case group. Work, schooling, sexuality, and reproductive health were analyzed using an ethno-epidemiological approach. Socioeconomic variables like work and schooling were strongly associated with childbearing in adolescence. An inverse linear association was observed between age at first dating and childbearing during adolescence (p < 0.001). Focusing on the contexts and social values (traditional and/or modern), pregnancy was: a positive consequence of an affective relationship with the partner; a way of exposing adolescent sexuality; and a means to achieve a certain social autonomy and other forms of social status within the age group.

Association between metabolic syndrome and bone fractures: a meta-analysis of observational studies.

PubMed

Sun, Kan; Liu, Jianmin; Lu, Nan; Sun, Hanxiao; Ning, Guang

2014-02-09

Emerging epidemiological evidence suggest an association between metabolic syndrome and fractures. However, whether metabolic syndrome is an independent risk or protective factor of fractures remains controversial. Our goal is to provide a quantitative assessment of the association between metabolic syndrome and bone fractures by conducting a meta-analysis of observational studies. The PubMed and Embase database were searched through to March 2013 to identify studies that met pre-established inclusion criteria. Reference lists of retrieved articles were also reviewed. Summary effect estimates with 95% confidence intervals (CI) were derived using a fixed or random effects model, depending on the heterogeneity of the included studies. Eight epidemiologic studies involving 39,938 participants were included in the meta-analysis. In overall analysis, metabolic syndrome was not associated with prevalent fractures [pooled odds ratio (OR) 0.93, 95% CI 0.84 - 1.03] in cross-sectional studies or incident fractures [pooled relative risk (RR) 0.88, 95% CI 0.37 - 2.12] in prospective cohort studies. No evidence of heterogeneity was found in cross-sectional studies (p = 0.786, I2 = 0.0%). A substantial heterogeneity was detected in cohort studies (p = 0.001, I2 = 85.7%). No indication of significant publication bias was found either from Begg's test or Egger's test. Estimates of total effects were substantially consistent in the sensitivity and stratification analyses. The present meta-analysis of observational studies suggests that the metabolic syndrome has no explicit effect on bone fractures.

Choice of time-scale in Cox's model analysis of epidemiologic cohort data: a simulation study.

PubMed

Thiébaut, Anne C M; Bénichou, Jacques

2004-12-30

Cox's regression model is widely used for assessing associations between potential risk factors and disease occurrence in epidemiologic cohort studies. Although age is often a strong determinant of disease risk, authors have frequently used time-on-study instead of age as the time-scale, as for clinical trials. Unless the baseline hazard is an exponential function of age, this approach can yield different estimates of relative hazards than using age as the time-scale, even when age is adjusted for. We performed a simulation study in order to investigate the existence and magnitude of bias for different degrees of association between age and the covariate of interest. Age to disease onset was generated from exponential, Weibull or piecewise Weibull distributions, and both fixed and time-dependent dichotomous covariates were considered. We observed no bias upon using age as the time-scale. Upon using time-on-study, we verified the absence of bias for exponentially distributed age to disease onset. For non-exponential distributions, we found that bias could occur even when the covariate of interest was independent from age. It could be severe in case of substantial association with age, especially with time-dependent covariates. These findings were illustrated on data from a cohort of 84,329 French women followed prospectively for breast cancer occurrence. In view of our results, we strongly recommend not using time-on-study as the time-scale for analysing epidemiologic cohort data. 2004 John Wiley & Sons, Ltd.

The Great Smoky Mountains Study: Developmental epidemiology in the southeastern United States

PubMed Central

Costello, E. Jane; Copeland, William; Angold, Adrian

2016-01-01

The Great Smoky Mountains Study (GSMS) is a study of child psychiatric epidemiology that began in 1992 to look at need for mental health services in a rural area of the USA. Over 20 years it has expanded its range to include developmental epidemiology more generally: not only the development of psychiatric and substance abuse problems but also their correlates and predictors: family and environmental risk, physical development including puberty, stress and stress-related hormones, trauma, the impact of poverty, genetic markers, and epigenetics. Now that participants are in their 30s the focus has shifted to adult outcomes of childhood psychopathology and risk, and early physical, cognitive, and psychological markers of aging. This paper describes the historical background of the study, its contributions to science and policy, and plans for the future. PMID:27010203

Epidemiology of urban water distribution systems

NASA Astrophysics Data System (ADS)

Bardet, Jean-Pierre; Little, Richard

2014-08-01

Urban water distribution systems worldwide contain numerous old and fragile pipes that inevitably break, flood streets and damage property, and disrupt economic and social activities. Such breaks often present dramatically in temporal clusters as occurred in Los Angeles during 2009. These clustered pipe breaks share many characteristics with human mortality observed during extreme climatological events such as heat waves or air pollution. Drawing from research and empirical studies in human epidemiology, a framework is introduced to analyze the time variations of disruptive pipe breaks that can help water agencies better understand clustered pipe failures and institute measures to minimize the disruptions caused by them. It is posited that at any time, a cohort of the pipes comprising the water distribution system will be in a weakened state due to fatigue and corrosion. This frail cohort becomes vulnerable during normal operations and ultimately breaks due to rapid increase in crack lengths induced by abnormal stressors. The epidemiological harvesting model developed in this paper simulates an observed time series of monthly pipe breaks and has both explanatory and predictive power. It also demonstrates that models from nonengineering disciplines such as medicine can provide improved insights into the performance of infrastructure systems.

Design and implementation of observational studies to measure disease burden with a focus on stroke.

PubMed

Howard, George; Howard, Virginia J

2018-02-01

Observational epidemiological studies have the dual goals of measuring disease burden and assessing the association between exposures and outcomes. This report focuses on the first of these goals and provides an overview of design considerations of commonly used approaches, specifically community surveillance studies, cross-sectional studies, and longitudinal cohort studies. Each of these designs has strengths and weaknesses, with no study design being superior in all cases. Rather, these designs are complementary to achieve a better understanding of the burden of stroke.

Observational studies and the difficult quest for causality: lessons from vaccine effectiveness and impact studies.

PubMed

Lipsitch, Marc; Jha, Ayan; Simonsen, Lone

2016-12-01

Although randomized placebo-controlled trials (RCT) are critical to establish efficacy of vaccines at the time of licensure, important remaining questions about vaccine effectiveness (VE)-used here to include individual-level measures and population-wide impact of vaccine programmes-can only be answered once the vaccine is in use, from observational studies. However, such studies are inherently at risk for bias. Using a causal framework and illustrating with examples, we review newer approaches to detecting and avoiding confounding and selection bias in three major classes of observational study design: cohort, case-control and ecological studies. Studies of influenza VE, especially in seniors, are an excellent demonstration of the challenges of detecting and reducing such bias, and so we use influenza VE as a running example. We take a fresh look at the time-trend studies often dismissed as 'ecological'. Such designs are the only observational study design that can measure the overall effect of a vaccination programme [indirect (herd) as well as direct effects], and are in fact already an important part of the evidence base for several vaccines currently in use. Despite the great strides towards more robust observational study designs, challenges lie ahead for evaluating best practices for achieving robust unbiased results from observational studies. This is critical for evaluation of national and global vaccine programme effectiveness. © The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

Tele-electrocardiography in the epidemiological 'Study of Health in Pomerania' (SHIP).

PubMed

Alte, Dietrich; Völzke, Henry; Robinson, Daniel M; Kleine, Volker; Grabe, Hans Jörgen; John, Ulrich; Felix, Stephan B

2006-01-01

We have evaluated a portable electrocardiogram (ECG) card in the large population-based epidemiological 'Study of Health in Pomerania' (SHIP). In all, 7008 men and women (20-79 years) were randomly selected from population registries and 4310 subjects participated. Participants used an ECG card for four weeks and recorded two ECGs daily. The participants were also encouraged to record additional ECGs in the case of symptomatic arrhythmias, chest pain or dizziness. The ECGs were sent via telephone. Acrobat (.pdf) files arrived at the study centre via email. Arrhythmias were analysed by visual ECG inspection. Seventy-one per cent of the participants sent at least 80% of the requested ECGs for four weeks. There were few problems (about 70) in the total of 38,162 ECGs transmitted. Overall, 94% of all ECGs were rated as 'good'. Physicians required about 1.5 h to read approximately 100 ECGs daily. The functionality and ergonomics of ECG cards appear to be sufficiently developed for large-scale use in epidemiological studies.

Lessons to learn from epidemiologic studies in ARDS.

PubMed

McNicholas, Bairbre A; Rooney, Grainne M; Laffey, John G

2018-02-01

Recent advances in our understanding of the epidemiology of ARDS has generated key insights into the incidence, risk factors, demographics, management and outcomes from this devastating clinical syndrome. ARDS occurs in 10% of all ICU patients, in 23% of all mechanically ventilated patients, with 5.5 cases per ICU bed each year. Although some regional variation exists regarding ARDS incidence, this may be less than previously thought. Subphenotypes are increasingly identified within the ARDS cohort, with studies identifying a 'hyperinflammatory' or 'reactive' subgroup that has a higher mortality, and may respond differently to therapeutic interventions. Demographic factors, such as race, may also affect the therapeutic response. Although mortality in ARDS is decreasing in clinical trials, it remains unchanged at approximately 40% in major observational studies. Modifiable ventilatory management factors, including PEEP, airway pressures, and respiratory rate are associated with mortality in ARDS. Hospital and ICU organizational factors play a role in outcome, whereas socioeconomic status is independently associated with survival in patients with ARDS. The Kigali adaptation of the Berlin ARDS definition may provide useful insights into the burden of ARDS in the developing world. ARDS exerts a substantial disease burden, with 40% of patients dying in hospital. Diverse factors, including patient-related factors such as age and illness severity, country level socioeconomic status, and ventilator management and ICU organizational factors each contribute to outcome from ARDS. Addressing these issues provides opportunities to improve outcome in patients with ARDS.

Comparative study on the epidemiological aspects of enterohemorrhagic Escherichia coli infections between Korea and Japan, 2006 to 2010.

PubMed

Lee, Won-Chang; Kwon, Young Hwan

2016-05-01

To compare the epidemiological aspects of enterohemorrhagic Escherichia coli (EHEC) between Korea and Japan by analyzing the current state of EHEC infection outbreaks and related risk factors. We investigated the epidemiological aspects of EHEC infection cases between Korea and Japan from 2006 to 2010. The following factors were analyzed: national prevalence rate (PR), regional prevalence rate, epidemic aspects (i.e., Cases related to gender), male to female morbidity ratio, age, and seasonal distribution. In total, there were 254 cases of EHEC with an average PR of 0.11 per 100,000 populations in Korea from 2006 to 2010. During the same period in Japan, there were 20,883 cases of EHEC with an average PR of 3.26 per 100,000 populations. The PR in Japan was significantly higher than that in Korea (p < 0.01). In both countries, more females than males had EHEC infections, with the highest incidence of infections (> 50%) observed for individuals younger than 9 years. EHEC is an emerging zoonosis and may be caused by consumption of raw or undercooked meat products from ruminants. This study provides a quantitative analysis of the epidemiological aspects and risk factors of EHEC infections in Korea and Japan and will provide insight on effective future strategies to reduce these infections.

Appendix C: Characterization of Uncertainty and Bias in Asbestos Epidemiological Data

EPA Pesticide Factsheets

Each of the epidemiological studies utilized in the fitting exercise described in this report provide data on the level of cumulative exposure in groups of workers and on the incidence of lung cancer or mesothelioma observed in those workers.

Methods for measuring utilization of mental health services in two epidemiologic studies

PubMed Central

NOVINS, DOUGLAS K.; BEALS, JANETTE; CROY, CALVIN; MANSON, SPERO M.

2015-01-01

Objectives of Study Psychiatric epidemiologic studies often include two or more sets of questions regarding service utilization, but the agreement across these different questions and the factors associated with their endorsement have not been examined. The objectives of this study were to describe the agreement of different sets of mental health service utilization questions that were included in the American Indian Service Utilization Psychiatric Epidemiology Risk and Protective Factors Project (AI-SUPERPFP), and compare the results to similar questions included in the baseline National Comorbidity Survey (NCS). Methods Responses to service utilization questions by 2878 AI-SUPERPFP and 5877 NCS participants were examined by calculating estimates of service use and agreement (κ) across the different sets of questions. Logistic regression models were developed to identify factors associated with endorsement of specific sets of questions. Results In both studies, estimates of mental health service utilization varied across the different sets of questions. Agreement across the different question sets was marginal to good (κ = 0.27–0.69). Characteristics of identified service users varied across the question sets. Limitations Neither survey included data to examine the validity of participant responses to service utilization questions. Recommendations for Further Research Question wording and placement appear to impact estimates of service utilization in psychiatric epidemiologic studies. Given the importance of these estimates for policy-making, further research into the validity of survey responses as well as impacts of question wording and context on rates of service utilization is warranted. PMID:18767205

DESIGN OF EXPOSURE MEASUREMENTS FOR EPIDEMIOLOGIC STUDIES

EPA Science Inventory

This presentation will describe the following items: (1) London daily air pollution and deaths that demonstrate how time series epidemiology can indicate that air pollution caused death; (2) Sophisticated statistical models required to establish this relationship for lower pollut...

'Mendelian randomization': an approach for exploring causal relations in epidemiology.

PubMed

Gupta, V; Walia, G K; Sachdeva, M P

2017-04-01

To assess the current status of Mendelian randomization (MR) approach in effectively influencing the observational epidemiology for examining causal relationships. Narrative review on studies related to principle, strengths, limitations, and achievements of MR approach. Observational epidemiological studies have repeatedly produced several beneficiary associations which were discarded when tested by standard randomized controlled trials (RCTs). The technique which is more feasible, highly similar to RCTs, and has the potential to establish a causal relationship between modifiable exposures and disease outcomes is known as MR. The technique uses genetic variants related to modifiable traits/exposures as instruments for detecting causal and directional associations with outcomes. In the last decade, the approach of MR has methodologically developed and progressed to a stage of high acceptance among the epidemiologists and is gradually expanding the landscape of causal relationships in non-communicable chronic diseases. Copyright © 2016 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

A proposal for assessing study quality: Biomonitoring, Environmental Epidemiology, and Short-lived Chemicals (BEES-C) instrument.

PubMed

LaKind, Judy S; Sobus, Jon R; Goodman, Michael; Barr, Dana Boyd; Fürst, Peter; Albertini, Richard J; Arbuckle, Tye E; Schoeters, Greet; Tan, Yu-Mei; Teeguarden, Justin; Tornero-Velez, Rogelio; Weisel, Clifford P

2014-12-01

The quality of exposure assessment is a major determinant of the overall quality of any environmental epidemiology study. The use of biomonitoring as a tool for assessing exposure to ubiquitous chemicals with short physiologic half-lives began relatively recently. These chemicals present several challenges, including their presence in analytical laboratories and sampling equipment, difficulty in establishing temporal order in cross-sectional studies, short- and long-term variability in exposures and biomarker concentrations, and a paucity of information on the number of measurements required for proper exposure classification. To date, the scientific community has not developed a set of systematic guidelines for designing, implementing and interpreting studies of short-lived chemicals that use biomonitoring as the exposure metric or for evaluating the quality of this type of research for WOE assessments or for peer review of grants or publications. We describe key issues that affect epidemiology studies using biomonitoring data on short-lived chemicals and propose a systematic instrument--the Biomonitoring, Environmental Epidemiology, and Short-lived Chemicals (BEES-C) instrument--for evaluating the quality of research proposals and studies that incorporate biomonitoring data on short-lived chemicals. Quality criteria for three areas considered fundamental to the evaluation of epidemiology studies that include biological measurements of short-lived chemicals are described: 1) biomarker selection and measurement, 2) study design and execution, and 3) general epidemiological study design considerations. We recognize that the development of an evaluative tool such as BEES-C is neither simple nor non-controversial. We hope and anticipate that the instrument will initiate further discussion/debate on this topic. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

A proposal for assessing study quality: Biomonitoring, Environmental Epidemiology, and Short-lived Chemicals (BEES-C) instrument

PubMed Central

LaKind, Judy S.; Sobus, Jon R.; Goodman, Michael; Barr, Dana Boyd; Fürst, Peter; Albertini, Richard J.; Arbuckle, Tye E.; Schoeters, Greet; Tan, Yu-Mei; Teeguarden, Justin; Tornero-Velez, Rogelio; Weisel, Clifford P.

2015-01-01

The quality of exposure assessment is a major determinant of the overall quality of any environmental epidemiology study. The use of biomonitoring as a tool for assessing exposure to ubiquitous chemicals with short physiologic half-lives began relatively recently. These chemicals present several challenges, including their presence in analytical laboratories and sampling equipment, difficulty in establishing temporal order in cross-sectional studies, short- and long-term variability in exposures and biomarker concentrations, and a paucity of information on the number of measurements required for proper exposure classification. To date, the scientific community has not developed a set of systematic guidelines for designing, implementing and interpreting studies of short-lived chemicals that use biomonitoring as the exposure metric or for evaluating the quality of this type of research for WOE assessments or for peer review of grants or publications. We describe key issues that affect epidemiology studies using biomonitoring data on short-lived chemicals and propose a systematic instrument – the Biomonitoring, Environmental Epidemiology, and Short-lived Chemicals (BEES-C) instrument – for evaluating the quality of research proposals and studies that incorporate biomonitoring data on short-lived chemicals. Quality criteria for three areas considered fundamental to the evaluation of epidemiology studies that include biological measurements of short-lived chemicals are described: 1) biomarker selection and measurement, 2) study design and execution, and 3) general epidemiological study design considerations. We recognize that the development of an evaluative tool such as BEES-C is neither simple nor non-controversial. We hope and anticipate that the instrument will initiate further discussion/debate on this topic. PMID:25137624

Using Accelerometers to Measure Physical Activity in Large-Scale Epidemiologic Studies: Issues and Challenges

PubMed Central

Lee, I-Min; Shiroma, Eric J

2013-01-01

Background Current guidelines for aerobic activity require that adults carry out ≥150 minutes/week of moderate-intensity physical activity, with a large body of epidemiologic evidence showing this level of activity to decrease the incidence of many chronic diseases. Less is known about whether light-intensity activities also have such benefits, and whether sedentary behavior is an independent predictor of increased risks of these chronic diseases, as imprecise assessments of these behaviours and cross-sectional study designs have limited knowledge to date. Methods Recent technological advances in assessment methods have made the use of movement sensors, such as the accelerometer, feasible for use in longitudinal, large-scale epidemiologic studies. Several such studies are collecting sensor-assessed, objective measures of physical activity with the aim of relating these to the development of clinical endpoints. This is a relatively new area of research; thus, in this paper, we use the Women’s Health Study (WHS) as a case study to illustrate challenges related to data collection, data processing, and analyses of the vast amount of data collected. Results The WHS plans to collect 7 days of accelerometer-assessed physical activity and sedentary behavior in ~18,000 women aged ≥62 years. Several logistical challenges exist in collecting data; nonetheless as of 31 August 2013, 11,590 women have already provided some data. Additionally, the WHS experience on data reduction and data analyses can help inform other similar large-scale epidemiologic studies. Conclusions Important data on the health effects of light-intensity activity and sedentary behaviour will emerge from large-scale epidemiologic studies collecting objective assessments of these behaviours. PMID:24297837

Thimerosal-Containing Vaccines and Autism: A Review of Recent Epidemiologic Studies

PubMed Central

Hurley, Anne M.; Tadrous, Mina; Miller, Elizabeth S.

2010-01-01

Although epidemiologic evidence has not supported the hypothesis of a causal relationship between thimerosal-containing vaccines and autism, concerns continue about pediatric exposure to mercury through vaccine administration. A statement issued by the American Academy of Pediatrics and the US Public Health Service in 1999 prompted the removal of thimerosal from many vaccines. In 2004, the Immunization Safety Review Committee of the Institute of Medicine rejected the hypothesis of a causal relationship between thimerosal-containing vaccines and autism. In a search of MEDLINE and EMBASE, we identified articles that address the potential association between thimerosal and neurodevelopmental disorders, specifically autism. In this article, we review recent pharmacokinetic and epidemiologic studies published between 2003 and 2008 regarding the proposed link between thimerosal and autism. PMID:22477809

Thimerosal-containing vaccines and autism: a review of recent epidemiologic studies.

PubMed

Hurley, Anne M; Tadrous, Mina; Miller, Elizabeth S

2010-07-01

Although epidemiologic evidence has not supported the hypothesis of a causal relationship between thimerosal-containing vaccines and autism, concerns continue about pediatric exposure to mercury through vaccine administration. A statement issued by the American Academy of Pediatrics and the US Public Health Service in 1999 prompted the removal of thimerosal from many vaccines. In 2004, the Immunization Safety Review Committee of the Institute of Medicine rejected the hypothesis of a causal relationship between thimerosal-containing vaccines and autism.In a search of MEDLINE and EMBASE, we identified articles that address the potential association between thimerosal and neurodevelopmental disorders, specifically autism. In this article, we review recent pharmacokinetic and epidemiologic studies published between 2003 and 2008 regarding the proposed link between thimerosal and autism.

[Differences between proposals for implementation of the social class concept in epidemiological studies

PubMed

Solla

1996-07-01

This article compares different proposals for the implementation of the concept of social class and analyzes the alternatives used in each proposal, considering previous epidemiological studies on this issue and the potential of such a concept as a central category in studies on social determination in the health/disease process. Seven basic differences were identified, pertaining to the following aspects: class structure; research objective; the social class concept as a reference; the decision as to which individual has his/her occupational activity taken as defining the family's social class; the class status of the unemployed, housewives, and the retired; class status of students; and criteria for distinguishing between the "bourgeoisie", "petty bourgeoisie", "new petty bourgeoisie", and "proletariat" and whether there is a specific flow in certain population groups. Given the observed differences and underlying theoretical models, this study discusses problems related to the fact that the use of a specific concept of social class can have various implementation models.

Study designs may influence results: the problems with questionnaire-based case-control studies on the epidemiology of glioma.

PubMed

Johansen, Christoffer; Schüz, Joachim; Andreasen, Anne-Marie Serena; Dalton, Susanne Oksbjerg

2017-03-28

Glioma is a rare brain tumour with a very poor prognosis and the search for modifiable factors is intense. We reviewed the literature concerning risk factors for glioma obtained in case-control designed epidemiological studies in order to discuss the influence of this methodology on the observed results. When reviewing the association between three exposures, medical radiation, exogenous hormone use and allergy, we critically appraised the evidence from both case-control and cohort studies. For medical radiation and hormone replacement therapy (HRT), questionnaire-based case-control studies appeared to show an inverse association, whereas nested case-control and cohort studies showed no association. For allergies, the inverse association was observed irrespective of study design. We recommend that the questionnaire-based case-control design be placed lower in the hierarchy of studies for establishing cause-and-effect for diseases such as glioma. We suggest that a state-of-the-art case-control study should, as a minimum, be accompanied by extensive validation of the exposure assessment methods and the representativeness of the study sample with regard to the exposures of interest. Otherwise, such studies cannot be regarded as 'hypothesis testing' but only 'hypothesis generating'. We consider that this holds true for all questionnaire-based case-control studies on cancer and other chronic diseases, although perhaps not to the same extent for each exposure-outcome combination.

MOLECULAR EPIDEMIOLOGICAL STUDIES ON TWO CYCLOSPORIASIS OUTBREAKS IN VANCOUVER, BRITISH COLUMBIA

EPA Science Inventory

Two cyclosporiasis outbreaks in Vancouver, British Columbia (BC) were investigated using molegular epidemiology. The cause of the 1999 outbreak has not been identiifed whereas the 2001 oubreak has been linked epidemiologically to the consumption of Thai basil. The internal tran...

Why is it important to study malaria epidemiology in India?

PubMed

Singh, Vineeta; Mishra, Neelima; Awasthi, Gauri; Dash, Aditya P; Das, Aparup

2009-10-01

Malaria is a major vector-borne disease in India. Based on vast geographic areas with associated topographic and climatic diversity, the variable malaria epidemiology in India is associated with high parasite genetic diversity and rapidly evolving drug resistance, differential distribution of vector species and emerging insecticide resistance and underlying human genetic diversity and past evolutionary histories. Further, changing climatic patterns have possibly changed malaria epidemiology to a great extent. The outcome of these changes is an increased incidence of Plasmodium falciparum over the P. vivax malaria in recent years. Accordingly, the drug and insecticide application policy in India has changed too. The above facts and associated rapid shifting trend of malaria epidemiology makes India a hot-spot for malaria research.

Long-term epidemiological studies of atomic bomb survivors in Hiroshima and Nagasaki: study populations, dosimetry and summary of health effects.

PubMed

Okubo, Toshiteru

2012-10-01

The Radiation Effects Research Foundation succeeded 28 years' worth of activities of the Atomic Bomb Casualty Commission on long-term epidemiological studies in Hiroshima and Nagasaki. It has three major cohorts of atomic bomb survivors, i.e. the Life Span Study (LSS) of 120,000 people, the In Utero Cohort of 3600 and the Second Generation Study (F(1)) of 77,000. The LSS and F(1) studies include a periodic health examination for each sub-cohort, i.e. the Adult Health Study and the F(1) Clinical Study, respectively. An extensive individual dose estimation was conducted and the system was published as the Dosimetry System established in 2002 (DS02). As results of these studies, increases of cancers in relation to dose were clearly shown. Increases of other mortality causes were also observed, including heart and respiratory diseases. There has been no evidence of genetic effects in the survivors' children, including cancer and other multi-factorial diseases. The increase in the expected mortality number in the next 10 y would allow the analyses of further details of the observed effects related to atomic bomb exposures.

New developments in epidemiology, diagnosis, and treatment of fascioliasis.

PubMed

Cabada, Miguel M; White, A Clinton

2012-10-01

This review focuses on the recent developments in the epidemiology, burden of disease, diagnostic tests, and treatment of fascioliasis. Recent epidemiologic data suggest that either the endemic areas are expanding or disease is being recognized in areas where it was not previously observed. In addition, recent data highlight the effects of fascioliasis on childhood anemia and nutrition. Diagnosis remains problematic, but newer diagnostic tests including antibody, antigen, and DNA detection tests may facilitate earlier diagnosis. Recent studies suggest that point-of-care testing may soon be possible. Treatment with triclabendazole is effective, but resistance is emerging in livestock and may pose a threat for patients. Fascioliasis continues to emerge as an important neglected disease, with new studies highlighting the under-recognized burden of disease. Further studies are needed on burden of disease, improved diagnosis, and alternative to triclabendazole treatment.

Review of epidemiological studies on drinking water hardness and cardiovascular diseases.

PubMed

Monarca, Silvano; Donato, Francesco; Zerbini, Ilaria; Calderon, Rebecca L; Craun, Gunther F

2006-08-01

Major risk factors do not entirely explain the worldwide variability of morbidity and mortality due to cardiovascular disease. Environmental exposures, including drinking water minerals may affect cardiovascular disease risks. We conducted a qualitative review of the epidemiological studies of cardiovascular disease and drinking water hardness and calcium and magnesium levels. Many but not all ecological studies found an inverse (i.e., protective) association between cardiovascular disease mortality and water hardness, calcium, or magnesium levels; but results are not consistent. Some case-control studies and one cohort study found either a reduced cardiovascular disease mortality risk with increased drinking water magnesium levels or an increased risk with low magnesium levels. However, the analytical studies provide little evidence that cardiovascular risks are associated with drinking water hardness or calcium levels. Information from epidemiological and other studies supports the hypothesis that a low intake of magnesium may increase the risk of dying from, and possibly developing, cardiovascular disease or stroke. Thus, not removing magnesium from drinking water, or in certain situations increasing the magnesium intake from water, may be beneficial, especially for populations with an insufficient dietary intake of the mineral.

Current practice of epidemiology in Africa: highlights of the 3rd conference of the African epidemiological association and 1st conference of the Cameroon society of epidemiology, Yaoundé, Cameroon, 2014

PubMed Central

Nkwescheu, Armand Seraphin; Fokam, Joseph; Tchendjou, Patrice; Nji, Akindeh; Ngouakam, Hermann; Andre, Bita Fouda; Joelle, Sobngwi; Uzochukwu, Benjamin; Akinroye, Kingsley; Mbacham, Wilfred; Colizzi, Vittorio; Leke, Rose; Victora, Cesar

2015-01-01

As the study of disease occurrence and health indicators in human populations, Epidemiology is a dynamic field that evolves with time and geographical context. In order to update African health workers on current epidemiological practices and to draw awareness of early career epidemiologists on concepts and opportunities in the field, the 3rd African Epidemiology Association and the 1st Cameroon Society of Epidemiology Conference was organized in June 2-6, 2014 at the Yaoundé Mont Febe Hotel, in Cameroon. Under the theme«Practice of Epidemiology in Africa: Stakes, Challenges and Perspectives», the conference attracted close to five hundred guest and participants from all continents. The two main programs were the pre-conference course for capacity building of African Early Career epidemiologists, and the conference itself, providing a forum for scientific exchanges on recent epidemiological concepts, encouraging the use of epidemiological methods in studying large disease burden and neglected tropical diseases; and highlighting existing opportunities. PMID:26523191

Current practice of epidemiology in Africa: highlights of the 3rd conference of the African epidemiological association and 1st conference of the Cameroon society of epidemiology, Yaoundé, Cameroon, 2014.

PubMed

Nkwescheu, Armand Seraphin; Fokam, Joseph; Tchendjou, Patrice; Nji, Akindeh; Ngouakam, Hermann; Andre, Bita Fouda; Joelle, Sobngwi; Uzochukwu, Benjamin; Akinroye, Kingsley; Mbacham, Wilfred; Colizzi, Vittorio; Leke, Rose; Victora, Cesar

2015-01-01

As the study of disease occurrence and health indicators in human populations, Epidemiology is a dynamic field that evolves with time and geographical context. In order to update African health workers on current epidemiological practices and to draw awareness of early career epidemiologists on concepts and opportunities in the field, the 3(rd) African Epidemiology Association and the 1st Cameroon Society of Epidemiology Conference was organized in June 2-6, 2014 at the Yaoundé Mont Febe Hotel, in Cameroon. Under the theme«Practice of Epidemiology in Africa: Stakes, Challenges and Perspectives», the conference attracted close to five hundred guest and participants from all continents. The two main programs were the pre-conference course for capacity building of African Early Career epidemiologists, and the conference itself, providing a forum for scientific exchanges on recent epidemiological concepts, encouraging the use of epidemiological methods in studying large disease burden and neglected tropical diseases; and highlighting existing opportunities.

An Updated Review of Epidemiologic Studies on the Relationship Between Exposure to Whole-Body Vibration and Low Back Pain

NASA Astrophysics Data System (ADS)

Bovenzi, M.; Hulshof, C. T. J.

1998-08-01

The aim of this paper is to update the information on the epidemiologic evidence of the adverse health effects of whole-body vibration (WBV) on the spinal system by means of a review of the epidemiologic studies published between 1986 and 1996. In a systematic search of epidemiologic studies of low back pain (LBP) disorders and occupations with exposure to WBV, 37 articles were retrieved. The quality of each study was evaluated according to criteria concerning the assessment of vibration exposure, assessment of health effects, and methodology. The epidemiologic studies reaching an adequate score on each of the above mentioned criteria, were included in the final review. A meta-analysis was also conducted in order to combine the results of independent epidemiologic studies. After applying the selection criteria, 16 articles reporting the occurrence of LBP disorders in 19 WBV-exposed occupational groups, reached a sufficient score. The study design was cross-sectional for 13 occupational groups, longitudinal for 5 groups and of case-control type for one group. The main reasons for the exclusion of studies were insufficient quantitative information on WBV exposure and the lack of control groups. The findings of the selected studies and the results of the meta-analysis of both cross-sectional and cohort studies showed that occupational exposure to WBV is associated with an increased risk of LBP, sciatic pain, and degenerative changes in the spinal system, including lumbar intervertebral disc disorders. Owing to the cross-sectional design of the majority of the reviewed studies, this epidemiologic evidence is not sufficient to outline a clear exposure-response relationship between WBV exposure and LBP disorders. Upon comparing the epidemiological studies included in this review with those conducted before 1986, it is concluded that research design and the quality of exposure and health effect data in the field of WBV have improved in the last decade.

Snippets from the past: the evolution of Wade Hampton Frost's epidemiology as viewed from the American Journal of Hygiene/Epidemiology.

PubMed

Morabia, Alfredo

2013-10-01

Wade Hampton Frost, who was a Professor of Epidemiology at Johns Hopkins University from 1919 to 1938, spurred the development of epidemiologic methods. His 6 publications in the American Journal of Hygiene, which later became the American Journal of Epidemiology, comprise a 1928 Cutter lecture on a theory of epidemics, a survey-based study of tonsillectomy and immunity to Corynebacterium diphtheriae (1931), 2 papers from a longitudinal study of the incidence of minor respiratory diseases (1933 and 1935), an attack rate ratio analysis of the decline of diphtheria in Baltimore (1936), and a 1936 lecture on the age, time, and cohort analysis of tuberculosis mortality. These 6 American Journal of Hygiene /American Journal of Epidemiology papers attest that Frost's personal evolution mirrored that of the emerging "early" epidemiology: The scope of epidemiology extended beyond the study of epidemics of acute infectious diseases, and rigorous comparative study designs and their associated quantitative methods came to light.

Snippets From the Past: The Evolution of Wade Hampton Frost's Epidemiology as Viewed From the American Journal of Hygiene/Epidemiology

PubMed Central

Morabia, Alfredo

2013-01-01

Wade Hampton Frost, who was a Professor of Epidemiology at Johns Hopkins University from 1919 to 1938, spurred the development of epidemiologic methods. His 6 publications in the American Journal of Hygiene, which later became the American Journal of Epidemiology, comprise a 1928 Cutter lecture on a theory of epidemics, a survey-based study of tonsillectomy and immunity to Corynebacterium diphtheriae (1931), 2 papers from a longitudinal study of the incidence of minor respiratory diseases (1933 and 1935), an attack rate ratio analysis of the decline of diphtheria in Baltimore (1936), and a 1936 lecture on the age, time, and cohort analysis of tuberculosis mortality. These 6 American Journal of Hygiene /American Journal of Epidemiology papers attest that Frost's personal evolution mirrored that of the emerging “early” epidemiology: The scope of epidemiology extended beyond the study of epidemics of acute infectious diseases, and rigorous comparative study designs and their associated quantitative methods came to light. PMID:24022889

A 3-year prospective study of the epidemiology of acute respiratory viral infections in hospitalized children in Shenzhen, China.

PubMed

He, Ying; Lin, Guang-Yu; Wang, Qiong; Cai, Xiao-Ying; Zhang, Yin-Hui; Lin, Chuang-Xing; Lu, Chang-Dong; Lu, Xue-Dong

2014-07-01

The epidemiology of local viral etiologies is essential for the management of viral respiratory tract infections. Limited data are available in China to describe the epidemiology of viral respiratory infections, especially in small-medium cities and rural areas. To determine the viral etiology and seasonality of acute respiratory infections in hospitalized children, a 3-year study was conducted in Shenzhen, China. Nasopharyngeal aspirates from eligible children were collected. Influenza and other respiratory viruses were tested by molecular assays simultaneously. Data were analyzed to describe the frequency and seasonality. Of the 2025 children enrolled in the study, 971 (48.0%) were positive for at least one viral pathogen, in which 890 (91.7%) were <4 years of age. The three most prevalent viruses were influenza A (IAV; 35.8%), respiratory syncytial virus (RSV; 30.5%) and human rhinovirus (HRV; 21.5%). Co-infections were found in 302 cases (31.1%), and dual viral infection was dominant. RSV, HRV and IAV were the most frequent viral agents involved in co-infection. On the whole, the obvious seasonal peaks mainly from March to May were observed with peak strength varying from 1 year to another. This study provides a basic profile of the epidemiology of acute respiratory viral infection in hospitalized children in Shenzhen. The spectrum of viruses in the study site is similar to that in other places, but the seasonality is closely related to geographic position, different from that in big cities in northern China and neighboring Hong Kong. © 2014 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

A Review of Exposure Assessment Methods in Epidemiological Studies on Incinerators

PubMed Central

Ranzi, Andrea; De Leo, Giulio A.; Lauriola, Paolo

2013-01-01

Incineration is a common technology for waste disposal, and there is public concern for the health impact deriving from incinerators. Poor exposure assessment has been claimed as one of the main causes of inconsistency in the epidemiological literature. We reviewed 41 studies on incinerators published between 1984 and January 2013 and classified them on the basis of exposure assessment approach. Moreover, we performed a simulation study to explore how the different exposure metrics may influence the exposure levels used in epidemiological studies. 19 studies used linear distance as a measure of exposure to incinerators, 11 studies atmospheric dispersion models, and the remaining 11 studies a qualitative variable such as presence/absence of the source. All reviewed studies utilized residence as a proxy for population exposure, although residence location was evaluated with different precision (e.g., municipality, census block, or exact address). Only one study reconstructed temporal variability in exposure. Our simulation study showed a notable degree of exposure misclassification caused by the use of distance compared to dispersion modelling. We suggest that future studies (i) make full use of pollution dispersion models; (ii) localize population on a fine-scale; and (iii) explicitly account for the presence of potential environmental and socioeconomic confounding. PMID:23840228

Three decades of hospital epidemiology and the challenge of integrating Health Surveillance: reflections from a case study.

PubMed

Escosteguy, Claudia Caminha; Pereira, Alessandra Gonçalves Lisbôa; Medronho, Roberto de Andrade

2017-10-01

This study proposes a reflection on the uses and future prospects of hospital-based health surveillance based on the account of a pioneering experience in hospital epidemiology, the epidemiology service at the Hospital Federal dos Servidores do Estado - HFSE, which served as the basis for the creation of epidemiologic surveillance units in municipal and state hospitals in Rio de Janeiro, Brazil. The epidemiology service has combined epidemiological surveillance, continuing education, in-service training, research, and health service evaluation since 1986. The service is part of the national epidemiological surveillance network and was responsible for the notification of 55,747 cases between 1986 and 2016, most of which were the result of active search. The integration of various levels of health surveillance and health care makes classical control activities more agile and provides instruments for measuring. The important role played by the service in human resources training is evident in the training of 1,835 medical interns and 78 residents up to 2016. In addition, this experience has served as the basis for the implantation of several other hospital epidemiological surveillance units. Current challenges include the promotion of effective communication and coordination among the other health surveillance committees.

Epidemiology of melasma in Brazilian patients: a multicenter study.

PubMed

Hexsel, Doris; Lacerda, Davi A; Cavalcante, Andrea S; Machado Filho, Carlos A S; Kalil, Célia Luiza P V; Ayres, Eloísa L; Azulay-Abulafia, Luna; Weber, Magda B; Serra, Marcio S; Lopes, Nádya F P; Cestari, Tania F

2014-04-01

Melasma is an acquired, irregularly patterned, light to dark-brown hypermelanosis, with symmetric distribution mostly over the face. The aim of this study was to evaluate clinical characteristics and factors related to melasma in Brazilian patients. This was a cross-sectional, multicenter study performed in Brazil. Investigators examined and questioned 953 patients over 18 years of age on clinical characteristics and other factors related to their melasma. Melasma was more prevalent in women (97.5%) and in Fitzpatrick skin phototypes II (12.8%), III (36.3%), and IV (39.7%). Skin phototypes II and III and family history of melasma had early onset of the disorder when compared with skin phototypes IV, V, and VI (P<0.0001). Similar results were also observed when these same groups were compared with the absence of family history (P<0.0001). Extra-facial melasma was more frequent in postmenopausal women compared with those who were not experiencing menopause (14.2% vs. 3.5%, P<0.0001). Data suggested that the age of melasma onset are related to skin phototypes and family history. Additionally, extra-facial melasma was more common in menopausal women. This is the first study on the epidemiology of melasma in Brazil involving a large sample of the population. These data can be a source of new relevant research on the cause and development of melasma. © 2013 The International Society of Dermatology.

Family and Psychosocial Risk Factors in a Longitudinal Epidemiological Study of Adolescents.

ERIC Educational Resources Information Center

Cuffe, Steven P.; McKeown, Robert E.; Addy, Cheryl L.; Garrison, Carol Z.

2005-01-01

Objective: To study the association of family and social risk factors with psychopathology in a longitudinal study of adolescents. Method: From 1986 to 1988, 3,419 seventh through ninth graders were screened with the Center for Epidemiologic Studies Depression Scale. The top decile scorers and a random sample of the remainder were interviewed…

TRANSMISSION OF ENTERIC DISEASE ASSOCIATED WITH WASTEWATER IRRIGATION: A PROSPECTIVE EPIDEMIOLOGICAL STUDY

EPA Science Inventory

We conducted a prospective epidemiological study of possible enteric disease transmission by aerosolized pathogens from sprinkler irrigation of partially treated wastewater in 20 kibbutzim (colllective agricultural settlements) in Isreal between March 1981 and February 1982. Medi...

Radon exposure and the risk of leukemia: a review of epidemiological studies.

PubMed

Laurier, D; Valenty, M; Tirmarche, M

2001-09-01

Since the 1990's, several authors estimated that radon inhalation may deliver a small amount of irradiation to the red bone marrow, and consequently may increase the risk of leukemia in humans. The objective of this review is to conduct a critical analysis of epidemiologic results currently available concerning the relationship between radon exposure and the risk of leukemia. Nineteen ecological studies, six miner cohort studies, and eight case-control studies published between 1987 and 2000 are included in this review. The limitations associated with each of these studies are discussed. The results of the ecological studies are relatively concordant and suggest an association between radon concentrations and the risk of leukemia at a geographic level. But these ecological studies present important limitations, and some are only crude analyses. Moreover, the results of the cohort and case-control studies, based on individual data, do not show any significant association between radon exposure and leukemia risk. Our conclusion is that the overall epidemiologic results currently available do not provide evidence for an association between radon exposure and leukemia.

The Exposure Dimension of Environmental Epidemiology: A Critical but Under-ExploredStudy Quality Issue in Environmental Health

EPA Science Inventory

Epidemiological research plays a critical role in assessing the effects of various chemical, physical, oiological, and social exposures on human health both in the general population and the workplace. However, even epidemiological studies that are specifically designed to test c...

Brain Tumor Epidemiology: Consensus from the Brain Tumor Epidemiology Consortium (BTEC)

PubMed Central

Bondy, Melissa L.; Scheurer, Michael E.; Malmer, Beatrice; Barnholtz-Sloan, Jill S.; Davis, Faith G.; Il’yasova, Dora; Kruchko, Carol; McCarthy, Bridget J.; Rajaraman, Preetha; Schwartzbaum, Judith A.; Sadetzki, Siegal; Schlehofer, Brigitte; Tihan, Tarik; Wiemels, Joseph L.; Wrensch, Margaret; Buffler, Patricia A.

2010-01-01

Epidemiologists in the Brain Tumor Epidemiology Consortium (BTEC) have prioritized areas for further research. Although many risk factors have been examined over the past several decades, there are few consistent findings possibly due to small sample sizes in individual studies and differences between studies in subjects, tumor types, and methods of classification. Individual studies have generally lacked sufficient sample size to examine interactions. A major priority based on available evidence and technologies includes expanding research in genetics and molecular epidemiology of brain tumors. BTEC has taken an active role in promoting understudied groups such as pediatric brain tumors, the etiology of rare glioma subtypes, such as oligodendroglioma, and meningioma, which not uncommon, has only recently been systematically registered in the US. There is also a pressing need to bring more researchers, especially junior investigators, to study brain tumor epidemiology. However, relatively poor funding for brain tumor research has made it difficult to encourage careers in this area. We review the group’s consensus on the current state of scientific findings and present a consensus on research priorities to identify the important areas the science should move to address. PMID:18798534

Ultraviolet radiation and the eye: an epidemiologic study.

PubMed Central

Taylor, H R

1989-01-01

Circumstantial evidence from biochemical, animal, and epidemiologic studies suggests an association between exposure to UV-B radiation (290 nm to 320 nm) and cataract. Such an association had not been proven because it had not been possible to quantify ocular UV-B exposure of individuals or to reliably grade the type and severity of cataract in field studies. We undertook an epidemiologic survey of cataract among 838 watermen who work on the Chesapeake Bay. Their individual ocular UV-B exposure was quantified for each year of life over the age of 16, on the basis of a detailed occupational history combined with laboratory and field measurements of ocular UV-B exposure. Cataracts were graded by both type and severity through clinical and photographic means. SMD changes were ascertained by fundal photography. A general medical history was taken to discover potentially confounding factors. This study showed that people with cortical lens opacities had a 21% higher UV-B exposure at each year of life than people without these opacities. A doubling in lifetime UV-B exposure led to a 60% increase in the risk of cortical cataract, and those with a high annual UV-B exposure increased their risk of cortical cataract over threefold. Corneal changes, namely pterygium and CDK, were also strongly associated with high UV-B exposure. No association was found between nuclear lens opacities or macular degeneration and UV-B exposure. This study also indicated several simple, practical measures, such as wearing spectacles or a hat, that effectively protect the eye from UV-B exposure. Thus it is easily within the power of individuals to protect their eyes from excessive UV-B exposure and reduce their risk of cortical cataract. A program of public education in this area could be a cost-effective means of reducing this important disease. PMID:2562534

Exposure Assessment Issues in Epidemiology Studies of Phthalates

PubMed Central

Johns, Lauren E.; Cooper, Glinda S.; Galizia, Audrey; Meeker, John D.

2015-01-01

Purpose The purpose of this paper is to review exposure assessment issues that need to be addressed in designing and interpreting epidemiology studies of phthalates, a class of chemicals commonly used in consumer and personal care products. Specific issues include population trends in exposure, temporal reliability of a urinary metabolite measurement, and how well a single urine sample may represent longer-term exposure. The focus of this review is on seven specific phthalates: diethyl phthalate (DEP); di-n-butyl phthalate (DBP); diisobutyl phthalate (DiBP); butyl benzyl phthalate (BBzP); di(2-ethylhexyl) phthalate (DEHP); diisononyl phthalate (DiNP); and diisodecyl phthalate (DiDP). Methods Comprehensive literature search using multiple search strategies Results Since 2001, declines in population exposure to DEP, BBzP, DBP, and DEHP have been reported in the United States and Germany, but DEHP exposure has increased in China. Although the half-lives of various phthalate metabolites are relatively short (3 to 18 hours), the intraclass correlation coefficients (ICCs) for phthalate metabolites, based on spot and first morning urine samples collected over a week to several months, range from weak to moderate, with a tendency toward higher ICCs (greater temporal stability) for metabolites of the shorter-chained (DEP, DBP, DiBP and BBzP, ICCs generally 0.3 to 0.6) compared with those of the longer-chained (DEHP, DiNP, DiDP, ICCs generally 0.1 to 0.3) phthalates. Additional research on optimal approaches to addressing the issue of urine dilution in studies of associations between biomarkers and different type of health effects is needed. Conclusions In conclusion, the measurement of urinary metabolite concentrations in urine could serve as a valuable approach to estimating exposure to phthalates in environmental epidemiology studies. Careful consideration of the strengths and limitations of this approach when interpreting study results is required. PMID:26313703

Molecular epidemiology: new rules for new tools?

PubMed

Merlo, Domenico Franco; Sormani, Maria Pia; Bruzzi, Paolo

2006-08-30

Molecular epidemiology combines biological markers and epidemiological observations in the study of the environmental and genetic determinants of cancer and other diseases. The potential advantages associated with biomarkers are manifold and include: (a) increased sensitivity and specificity to carcinogenic exposures; (b) more precise evaluation of the interplay between genetic and environmental determinants of cancer; (c) earlier detection of carcinogenic effects of exposure; (d) characterization of disease subtypes-etiologies patterns; (e) evaluation of primary prevention measures. These, in turn, may translate into better tools for etiologic research, individual risk assessment, and, ultimately, primary and secondary prevention. An area that has not received sufficient attention concerns the validation of these biomarkers as surrogate endpoints for cancer risk. Validation of a candidate biomarker's surrogacy is the demonstration that it possesses the properties required for its use as a substitute for a true endpoint. The principles underlying the validation process underwent remarkable developments and discussion in therapeutic research. However, the challenges posed by the application of these principles to epidemiological research, where the basic tool for this validation (i.e., the randomized study) is seldom possible, have not been thoroughly explored. The validation process of surrogacy must be applied rigorously to intermediate biomarkers of cancer risk before using them as risk predictors at the individual as well as at the population level.

Joint Data Analysis in Nutritional Epidemiology: Identification of Observational Studies and Minimal Requirements.

PubMed

Pinart, Mariona; Nimptsch, Katharina; Bouwman, Jildau; Dragsted, Lars O; Yang, Chen; De Cock, Nathalie; Lachat, Carl; Perozzi, Giuditta; Canali, Raffaella; Lombardo, Rosario; D'Archivio, Massimo; Guillaume, Michèle; Donneau, Anne-Françoise; Jeran, Stephanie; Linseisen, Jakob; Kleiser, Christina; Nöthlings, Ute; Barbaresko, Janett; Boeing, Heiner; Stelmach-Mardas, Marta; Heuer, Thorsten; Laird, Eamon; Walton, Janette; Gasparini, Paolo; Robino, Antonietta; Castaño, Luis; Rojo-Martínez, Gemma; Merino, Jordi; Masana, Luis; Standl, Marie; Schulz, Holger; Biagi, Elena; Nurk, Eha; Matthys, Christophe; Gobbetti, Marco; de Angelis, Maria; Windler, Eberhard; Zyriax, Birgit-Christiane; Tafforeau, Jean; Pischon, Tobias

2018-02-01

Joint data analysis from multiple nutrition studies may improve the ability to answer complex questions regarding the role of nutritional status and diet in health and disease. The objective was to identify nutritional observational studies from partners participating in the European Nutritional Phenotype Assessment and Data Sharing Initiative (ENPADASI) Consortium, as well as minimal requirements for joint data analysis. A predefined template containing information on study design, exposure measurements (dietary intake, alcohol and tobacco consumption, physical activity, sedentary behavior, anthropometric measures, and sociodemographic and health status), main health-related outcomes, and laboratory measurements (traditional and omics biomarkers) was developed and circulated to those European research groups participating in the ENPADASI under the strategic research area of "diet-related chronic diseases." Information about raw data disposition and metadata sharing was requested. A set of minimal requirements was abstracted from the gathered information. Studies (12 cohort, 12 cross-sectional, and 2 case-control) were identified. Two studies recruited children only and the rest recruited adults. All studies included dietary intake data. Twenty studies collected blood samples. Data on traditional biomarkers were available for 20 studies, of which 17 measured lipoproteins, glucose, and insulin and 13 measured inflammatory biomarkers. Metabolomics, proteomics, and genomics or transcriptomics data were available in 5, 3, and 12 studies, respectively. Although the study authors were willing to share metadata, most refused, were hesitant, or had legal or ethical issues related to sharing raw data. Forty-one descriptors of minimal requirements for the study data were identified to facilitate data integration. Combining study data sets will enable sufficiently powered, refined investigations to increase the knowledge and understanding of the relation between food

[Scientific, practical and educational aspects of clinical epidemiology].

PubMed

Briko, N I

2012-01-01

This article defines clinical epidemiology and describes its goal and objectives. The author claims that clinical epidemiology is a section of epidemiology which underlies the development of evidence-based standards for diagnostics, treatment and prevention and helps to select the appropriate algorithm for each clinical case. The study provides a comprehensive overview of the relationship between clinical epidemiology and evidence-based medicine. Epidemiological research is shown to be methodological basis of clinical epidemiology and evidence-based medicine with randomized controlled trials being the "gold standard" for obtaining reliable data. The key stages in the history of clinical epidemiology are discussed and further development of clinical epidemiology and the integration of courses on clinical epidemiology in education is outlined for progress in medical research and health care practice.

Mapping epidemiology's past to inform its future: metaknowledge analysis of epidemiologic topics in leading journals, 1974-2013.

PubMed

Trinquart, Ludovic; Galea, Sandro

2015-07-15

An empiric perspective on what epidemiology has studied over time might inform discussions about future directions for the discipline. We aimed to identify the main areas of epidemiologic inquiry and determine how they evolved over time in 5 high-impact epidemiologic journals. We analyzed the titles and abstracts of 20,895 articles that were published between 1974 and 2013. In 5 time periods that reflected approximately equal numbers of articles, we identified the main topics by clustering terms based on co-occurrence. Infectious disease and cardiovascular disease epidemiology were the prevailing topics over the 5 periods. Cancer epidemiology was a major topic from 1974 to 2001 but disappeared thereafter. Nutritional epidemiology gained relative importance from 1974 to 2013. Environmental epidemiology appeared during 1996-2001 and continued to be important, whereas 2 clusters related to methodology and meta-analysis in genetics appeared during 2008-2013. Several areas of epidemiology, including injury or psychiatric epidemiology, did not make an appearance as major topics at any time. In an ancillary analysis of 6 high-impact general medicine journals, we found patterns of epidemiologic articles that were overall consistent with the findings in epidemiologic journals. This metaknowledge investigation allowed identification of the dominant topics in and conversely those that were absent from 5 major epidemiologic journals. We discuss implications for the field. © The Author 2015. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Genotyping of Giardia isolates in Scotland: a descriptive epidemiological study.

PubMed

Alexander, C; Jones, B; Inverarity, D; Pollock, K G J

2014-08-01

Giardiasis, caused by the intestinal protozoan parasite Giardia intestinalis (synonyms: G. lamblia, G. duodenalis), is one of the most frequent parasites to infect the Scottish population. Transmission of the infective cysts in faecal matter is commonly via food and/or water. Giardia is subdivided into assemblages, where clinical and epidemiological differences have been described between assemblages A and B. This snapshot descriptive epidemiological study examines 30 positive cases of Giardia of which 72% (n = 21) were shown to be assemblage A, 14% (n = 4) assemblage B and 10% (n = 3) mixed assemblages (A and B). There was a 2:3 female:male ratio of affected individuals with foreign travel recorded in 22 of these cases. The commonest symptom was diarrhoea which was reported in 80% of cases followed by tiredness. Five cases required hospitalization emphasizing the importance of gaining a greater understanding of how Giardia assemblages influence clinical outcomes to assist in formulating guidelines to manage potential Giardia outbreaks.

The Epidemiology of Delirium: Challenges and Opportunities for Population Studies

PubMed Central

Davis, Daniel H.J.; Kreisel, Stefan H.; Muniz Terrera, Graciela; Hall, Andrew J.; Morandi, Alessandro; Boustani, Malaz; Neufeld, Karin J.; Lee, Hochang Benjamin; MacLullich, Alasdair M.J.; Brayne, Carol

2013-01-01

Delirium is a serious and common acute neuropsychiatric syndrome that is associated with short- and long-term adverse health outcomes. However, relatively little delirium research has been conducted in unselected populations. Epidemiologic research in such populations has the potential to resolve several questions of clinical significance in delirium. Part 1 of this article explores the importance of population selection, case-ascertainment, attrition, and confounding. Part 2 examines a specific question in delirium epidemiology: What is the relationship between delirium and trajectories of cognitive decline? This section assesses previous work through two systematic reviews and proposes a design for investigating delirium in the context of longitudinal cohort studies. Such a design requires robust links between community and hospital settings. Practical considerations for case-ascertainment in the hospital, as well as the necessary quality control of these programs, are outlined. We argue that attention to these factors is important if delirium research is to benefit fully from a population perspective. PMID:23907068

Socio-epidemiological determinants of 2002 plague outbreak in Himachal Pradesh, India: a qualitative study

PubMed Central

2014-01-01

Background This qualitative investigation was conducted to determine the socio-epidemiological factors related to the plague outbreak (2002) in Himachal Pradesh (HP), India. Methods The data for socio-epidemiological factors related to the plague outbreak (2002) in HP was obtained from residents through 150 in-depth Interviews (IDI) and 30 Focus Group Discussions (FGD) during six visits (from May 2011 to April 2012) by the research team. Natives, health officials and the nomadic population were interviewed. According to their opinion and viewpoints data was collected and their lifestyle and hunting practices were studied in detail. Tape recorders were used during various FGDs and IDIs. The interviews and FGDs were later transcribed and coded. In-depth analysis of the recorded data was done using an inductive thematic analysis approach. Results The study reports that the outbreak in 2002 in a few villages of Himachal Pradesh was that of plague and it occurred by the contact of an index case with wild animals after hunting and de-skinning. The first wave of plague transmission which took 16 lives of residents was followed by a second wave of transmission in a ward of a tertiary care hospital where one visitor acquired it from relatives of the index case and succumbed. The life-style practices of residents (hunting behavior, long stay in caves and jungles, overcrowding in houses, poor hygiene and sanitation, belief in ‘God’ and faith healers for cure of diseases) was optimal for the occurrence and rapid spread of such a communicable disease. The man-rodent contact is intensified due to the practice of hunting in such a rodent-ridden environment. The residents harbor a strong belief that plague occurs due to the wrath of gods. Various un-reported outbreaks of plague were also observed by officials, residents and old folk. The persistence of plague in HP is favoured by its hilly terrain, inaccessible areas, inclement weather (snow) in winters, unhygienic lifestyle

Epidemiological and aetiological study on tinea pedis and onychomycosis in Algeria.

PubMed

Djeridane, Assya; Djeridane, Yasmina; Ammar-Khodja, Aomar

2006-05-01

Epidemiological studies on tinea pedis and onychomycosis, common fungal infections, have been conducted in many parts of the world. There are currently no studies of tinea pedis and/or onychomycosis in Algeria. The aim of this paper was to study the epidemiology of foot diseases, including tinea pedis and onychomycosis and to identify the aetiological factors of these infections in outpatients attending the Department of Dermatology of the Central Hospital of Army in Algiers, Algeria. A total of 1300 male subjects, mean age 35.9 +/- 16 years (range: 16-80) were recruited during the period November 2003 to November 2004 and were clinically examined. A complete dermatological examination was performed on all subjects, and skin and nail specimens of the feet were taken from those patients presenting signs of tinea pedis and/or onychomycosis for microscopy and fungal culture. Clinical diagnosis for tinea pedis and onychomycosis was suspected in 249 and 72 subjects, respectively, and confirmed in 197 and 60 cases, respectively, by positive cultures, resulting in a global prevalence of tinea pedis and toenail onychomycosis of 15% and 4.6% respectively. The age groups most commonly infected were 50-59 and 20-29 years. The yeast species Candida parapsilosis and the dermatophytic species Trichophyton rubrum were shown to be the most common pathogens in both tinea pedis (C. parapsilosis 20.4%; T. rubrum 17%) and onychomycosis (T. rubrum 35%; C. parapsilosis 28.3%). This is the first investigation dealing with fungal foot diseases in Algeria. The clinical and epidemiological data collected would serve as reference for future research and may be useful in the development of preventive and educational strategies.

Hume, Mill, Hill, and the Sui Generis Epidemiologic Approach to Causal Inference

PubMed Central

Morabia, Alfredo

2013-01-01

The epidemiologic approach to causal inference (i.e., Hill's viewpoints) consists of evaluating potential causes from the following 2, noncumulative angles: 1) established results from comparative, observational, or experimental epidemiologic studies; and 2) reviews of nonepidemiologic evidence. It does not involve statements of statistical significance. The philosophical roots of Hill's viewpoints are unknown. Superficially, they seem to descend from the ideas of Hume and Mill. Hill's viewpoints, however, use a different kind of evidence and have different purposes than do Hume's rules or Mill's system of logic. In a nutshell, Hume ignores comparative evidence central to Hill's viewpoints. Mill's logic disqualifies as invalid nonexperimental evidence, which forms the bulk of epidemiologic findings reviewed from Hill's viewpoints. The approaches by Hume and Mill cannot corroborate successful implementations of Hill's viewpoints. Besides Hume and Mill, the epidemiologic literature is clueless about a plausible, pre-1965 philosophical origin of Hill's viewpoints. Thus, Hill's viewpoints may be philosophically novel, sui generis, still waiting to be validated and justified. PMID:24071010

Hume, Mill, Hill, and the sui generis epidemiologic approach to causal inference.

PubMed

Morabia, Alfredo

2013-11-15

The epidemiologic approach to causal inference (i.e., Hill's viewpoints) consists of evaluating potential causes from the following 2, noncumulative angles: 1) established results from comparative, observational, or experimental epidemiologic studies; and 2) reviews of nonepidemiologic evidence. It does not involve statements of statistical significance. The philosophical roots of Hill's viewpoints are unknown. Superficially, they seem to descend from the ideas of Hume and Mill. Hill's viewpoints, however, use a different kind of evidence and have different purposes than do Hume's rules or Mill's system of logic. In a nutshell, Hume ignores comparative evidence central to Hill's viewpoints. Mill's logic disqualifies as invalid nonexperimental evidence, which forms the bulk of epidemiologic findings reviewed from Hill's viewpoints. The approaches by Hume and Mill cannot corroborate successful implementations of Hill's viewpoints. Besides Hume and Mill, the epidemiologic literature is clueless about a plausible, pre-1965 philosophical origin of Hill's viewpoints. Thus, Hill's viewpoints may be philosophically novel, sui generis, still waiting to be validated and justified.

Epidemiological bases and molecular mechanisms linking obesity, diabetes, and cancer.

PubMed

Gutiérrez-Salmerón, María; Chocarro-Calvo, Ana; García-Martínez, José Manuel; de la Vieja, Antonio; García-Jiménez, Custodia

2017-02-01

The association between diabetes and cancer was hypothesized almost one century ago. Today, a vast number of epidemiological studies support that obese and diabetic populations are more likely to experience tissue-specific cancers, but the underlying molecular mechanisms remain unknown. Obesity, diabetes, and cancer share many hormonal, immune, and metabolic changes that may account for the relationship between diabetes and cancer. In addition, antidiabetic treatments may have an impact on the occurrence and course of some cancers. Moreover, some anticancer treatments may induce diabetes. These observations aroused a great controversy because of the ethical implications and the associated commercial interests. We report an epidemiological update from a mechanistic perspective that suggests the existence of many common and differential individual mechanisms linking obesity and type 1 and 2 diabetes mellitus to certain cancers. The challenge today is to identify the molecular links responsible for this association. Classification of cancers by their molecular signatures may facilitate future mechanistic and epidemiological studies. Copyright © 2016 SEEN. Publicado por Elsevier España, S.L.U. All rights reserved.

Congenital syphilis, a reemergent disease in Mexico: its epidemiology during the last 2 decades.

PubMed

Reyna-Figueroa, Jesús; Esparza-Aguilar, Marcelino; Hernández-Hernández, Luz del Carmen; Fernández-Canton, Sonia; Richardson-Lopez Collada, Vesta Louise

2011-09-01

To describe the epidemiologic profile of congenital syphilis in Mexico between 1990 and 2009. The database of the General Direction of Epidemiology at the Ministry of Health in Mexico about congenital syphilis was reviewed. Data corresponding to the period between 1990 and 2009 were analyzed in every state of the Mexican republic. A total of 1717 cases of congenital syphilis were reported during the study period. A 16.6% increase was observed between 2005 and 2009 and the quinquennium between 2000 and 2004. A trend toward increase in the incidence of congenital syphilis was observed with 2.9 new cases for each 100,000 babies born alive. The states that displayed significant positive trends were as follows: Baja California, Colima, Chihuahua, Jalisco, Nayarit, Sinaloa, and Zacatecas. An increase in the number of cases of congenital syphilis is observed; the northern states are the ones that contribute the most to the statistics. There is a real need to refine the epidemiologic operations to detect and treat the cases of maternal and congenital syphilis in the country.

Causality in cancer epidemiology.

PubMed

Lagiou, Pagona; Adami, Hans-Olov; Trichopoulos, Dimitrios

2005-01-01

In this review, issues of causality in epidemiologic research with emphasis on the aetiology of human cancer are considered. Principles of assessing causation in epidemiological studies of cancer are distinguished into those concerning an individual study, several studies and a particular person. Strengths and weaknesses of various approaches of documenting carcinogenicity in humans are examined and lists of major established causes of human cancer are presented. The review concludes with estimates of mortality from cancer around the world that can be attributed to specific factors under the light of the current scientific knowledge.

Paradigms in epidemiology textbooks: in the footsteps of Thomas Kuhn.

PubMed Central

Bhopal, R

1999-01-01

This article attempts to contribute to the debate on the future of epidemiology by combining Thomas Kuhn's ideas on scientific paradigms with the author's observations on some epidemiology textbooks. The author's interpretations were based on his readings of Kuhn's The Structure of Scientific Revolutions, epidemiology textbooks, and papers on the future of epidemiology. Thomas Kuhn's view is that sciences mostly work with a single paradigm driven by exemplars of successful work, and that proposals for paradigm change are resisted. Sciences that are maturing or changing do not have a dominant paradigm. Epidemiology textbooks showed diversity in their concepts, content, and approach. Most exemplars related to etiologic research rather than public health practice. One key focus of the recent controversy regarding the role of epidemiology has been the increasing inability of epidemiology to solve socially based public health problems. Kuhn's views help explain the polarization of views expressed. Kuhn's philosophy of science offers insights into controversies such as whether a paradigm shift is needed or imminent and the gap between epidemiology and public health practice. Interaction between science philosophers, epidemiologists, and public health practitioners may be valuable. PMID:10432899

Paradigms in epidemiology textbooks: in the footsteps of Thomas Kuhn.

PubMed

Bhopal, R

1999-08-01

This article attempts to contribute to the debate on the future of epidemiology by combining Thomas Kuhn's ideas on scientific paradigms with the author's observations on some epidemiology textbooks. The author's interpretations were based on his readings of Kuhn's The Structure of Scientific Revolutions, epidemiology textbooks, and papers on the future of epidemiology. Thomas Kuhn's view is that sciences mostly work with a single paradigm driven by exemplars of successful work, and that proposals for paradigm change are resisted. Sciences that are maturing or changing do not have a dominant paradigm. Epidemiology textbooks showed diversity in their concepts, content, and approach. Most exemplars related to etiologic research rather than public health practice. One key focus of the recent controversy regarding the role of epidemiology has been the increasing inability of epidemiology to solve socially based public health problems. Kuhn's views help explain the polarization of views expressed. Kuhn's philosophy of science offers insights into controversies such as whether a paradigm shift is needed or imminent and the gap between epidemiology and public health practice. Interaction between science philosophers, epidemiologists, and public health practitioners may be valuable.

Unmanned Aircraft Systems for Studying Spatial Abundance of Ungulates: Relevance to Spatial Epidemiology

PubMed Central

Barasona, José A.; Mulero-Pázmány, Margarita; Acevedo, Pelayo; Negro, Juan J.; Torres, María J.; Gortázar, Christian; Vicente, Joaquín

2014-01-01

Complex ecological and epidemiological systems require multidisciplinary and innovative research. Low cost unmanned aircraft systems (UAS) can provide information on the spatial pattern of hosts’ distribution and abundance, which is crucial as regards modelling the determinants of disease transmission and persistence on a fine spatial scale. In this context we have studied the spatial epidemiology of tuberculosis (TB) in the ungulate community of Doñana National Park (South-western Spain) by modelling species host (red deer, fallow deer and cattle) abundance at fine spatial scale. The use of UAS high-resolution images has allowed us to collect data to model the environmental determinants of host abundance, and in a further step to evaluate their relationships with the spatial risk of TB throughout the ungulate community. We discuss the ecological, epidemiological and logistic conditions under which UAS may contribute to study the wildlife/livestock sanitary interface, where the spatial aggregation of hosts becomes crucial. These findings are relevant for planning and implementing research, fundamentally when managing disease in multi-host systems, and focusing on risky areas. Therefore, managers should prioritize the implementation of control strategies to reduce disease of conservation, economic and social relevance. PMID:25551673

Epidemiology of cervical cancer in Latin America.

PubMed

Capote Negrin, Luis G

2015-01-01

The basic aspects of the descriptive epidemiology of cervical cancer in Latin America are presented. A decrease in the incidence and mortality rates has been observed in the period from 2000 to 2012 in all countries across the region, this has not occurred at the same proportions, and in many countries, observed figures of incidence and mortality are among the highest levels in the world. In Latin America, calculating a mean measure of the numbers from the GLOBOCAN data from 2000 to 2012, we can observe a difference of up to fivefold of the incidence (Puerto Rico 9,73 Vs Bolivia 50,73) and almost seven times for mortality (Puerto Rico 3,3 Vs Nicaragua 21,67). A report of the epidemiology, risk factors, and evaluation of screening procedures regarding the possible impact of the human papillomavirus (HPV) vaccine I in the prevention of cervical cancer is presented.

Epidemiology of cervical cancer in Latin America

PubMed Central

Capote Negrin, Luis G

2015-01-01

The basic aspects of the descriptive epidemiology of cervical cancer in Latin America are presented. A decrease in the incidence and mortality rates has been observed in the period from 2000 to 2012 in all countries across the region, this has not occurred at the same proportions, and in many countries, observed figures of incidence and mortality are among the highest levels in the world. In Latin America, calculating a mean measure of the numbers from the GLOBOCAN data from 2000 to 2012, we can observe a difference of up to fivefold of the incidence (Puerto Rico 9,73 Vs Bolivia 50,73) and almost seven times for mortality (Puerto Rico 3,3 Vs Nicaragua 21,67). A report of the epidemiology, risk factors, and evaluation of screening procedures regarding the possible impact of the human papillomavirus (HPV) vaccine I in the prevention of cervical cancer is presented. PMID:26557875

First Molecular Epidemiological Study of Cutaneous Leishmaniasis in Libya

PubMed Central

Amro, Ahmad; Gashout, Aisha; Al-Dwibe, Hamida; Zahangir Alam, Mohammad; Annajar, Badereddin; Hamarsheh, Omar; Shubar, Hend; Schönian, Gabriele

2012-01-01

Background Cutaneous leishmaniasis (CL) is a major public health problem in Libya. The objective of this study was to investigate, for the first time, epidemiological features of CL outbreaks in Libya including molecular identification of parasites, the geographical distribution of cases and possible scenarios of parasite transmission. Methodology/Principal Findings We studied 450 patients that came from 49 areas distributed in 12 districts in north-west Libya. The patients' ages ranged from 9 months to 87 years (median age 25 years); 54% of the cases were males. Skin scrapings spotted on glass slides were collected for molecular identification of causative agent. The ribosomal internal transcribed spacer 1 (ITS1) was amplified and subsequently characterized by restriction fragment length polymorphism (RFLP) analysis. In total, 195 samples were successfully identified of which 148 (75.9%) were Leishmania major, and 47 (24.1%) Leishmania tropica. CL cases infected with L. major were found in all CL areas whereas L. tropica cases came mainly from Al Jabal Al Gharbi (46.4%), Misrata (17.8%) and Tarhuna districts (10.7%). A trend of seasonality was noticed for the infections with L. major which showed a clear peak between November and January, but was less pronounced for infections by L. tropica. Conclusion The first molecular study on CL in Libya revealed that the disease is caused by L. major and L. tropica and the epidemiological patterns in the different foci were the same as in other Mediterranean foci of CL. PMID:22724036

First molecular epidemiological study of cutaneous leishmaniasis in Libya.

PubMed

Amro, Ahmad; Gashout, Aisha; Al-Dwibe, Hamida; Zahangir Alam, Mohammad; Annajar, Badereddin; Hamarsheh, Omar; Shubar, Hend; Schönian, Gabriele

2012-01-01

Cutaneous leishmaniasis (CL) is a major public health problem in Libya. The objective of this study was to investigate, for the first time, epidemiological features of CL outbreaks in Libya including molecular identification of parasites, the geographical distribution of cases and possible scenarios of parasite transmission. We studied 450 patients that came from 49 areas distributed in 12 districts in north-west Libya. The patients' ages ranged from 9 months to 87 years (median age 25 years); 54% of the cases were males. Skin scrapings spotted on glass slides were collected for molecular identification of causative agent. The ribosomal internal transcribed spacer 1 (ITS1) was amplified and subsequently characterized by restriction fragment length polymorphism (RFLP) analysis. In total, 195 samples were successfully identified of which 148 (75.9%) were Leishmania major, and 47 (24.1%) Leishmania tropica. CL cases infected with L. major were found in all CL areas whereas L. tropica cases came mainly from Al Jabal Al Gharbi (46.4%), Misrata (17.8%) and Tarhuna districts (10.7%). A trend of seasonality was noticed for the infections with L. major which showed a clear peak between November and January, but was less pronounced for infections by L. tropica. The first molecular study on CL in Libya revealed that the disease is caused by L. major and L. tropica and the epidemiological patterns in the different foci were the same as in other Mediterranean foci of CL.

How much, how long, what, and where: air pollution exposure assessment for epidemiologic studies of respiratory disease.

PubMed

Brauer, Michael

2010-05-01

Epidemiology has played an important role in the understanding of air pollution as a risk factor for respiratory disease and in the evidence base for air quality standards. With the widespread availability of genetic information and increasingly sophisticated measurements of molecular markers of adverse effects, there is a need for more specific and precise assessment of exposure to maximize the potential information to be derived from epidemiologic studies. Here advances in air pollution exposure assessment and their applications to studies of respiratory disease are reviewed, with a focus on recent studies of traffic-related air pollution and asthma. Although continuous measurements of personal exposures for all study subjects for a complete study period might be considered the desired "gold standard" for exposure, this is rarely, if ever, achieved due to feasibility constraints. Given this, exposure is typically estimated using models. Recent applications of geospatial (e.g., land use regression) models to studies of respiratory disease have made possible new study designs focused on spatial variability in exposure within urban areas and have provided new insights into the potential role of traffic-related air pollution (TRAP) as a risk factor for the development of childhood asthma. Substantial uncertainty remains, however, regarding what agent(s) within TRAP might be responsible for the observed associations. Future research will require increasing the specificity of exposure assessment to identify the potential roles of individual air pollution components, to elucidate potential mechanisms, and to facilitate studies of mixtures and gene-air pollution interactions.

Epidemiological study of canine parvovirus infection in and around Bhubaneswar, Odisha, India.

PubMed

Behera, Monalisa; Panda, S K; Sahoo, P K; Acharya, A P; Patra, R C; Das, Sweta; Pati, S

2015-01-01

An epidemiological study of canine parvovirus infection in dogs in and around Bhubaneswar, Odisha was conducted between December 2012 to March 2013 and prevalence rate was studied on the basis of age, breed, and sex. A total of 71 fecal samples from suspected diarrheic dogs were collected in sterile phosphate buffer saline (10% W/V) and examined by polymerase chain reaction (PCR) for detection of canine parvo virus infection, followed by epidemiological study in relation to age, breed, and sex. Of 71 samples analyzed, 29 (40.85%) were found to be positive by PCR assay. The infection was higher in Deshi/local breeds (34.48%), followed by German shepherd (17.24%), equal incidences in mixed and Labrador retriever (10.34%), Rottweiler and German spitz showed 6.90% each and finally lower incidences in four breeds (3.45%) such as Dalmatians, Nea politan mastiff, Pug and Great Dane. Age-wise prevalence study revealed the infection being more in the age group of 3-6 months (41.37%), followed by equal incidences of 27.59% in 1-3 months and 6-12 months age group, and a low incidence in age groups above 12 months (3.45%). The incidence was predominantly higher in males (86.21%) than females (13.79%). The epidemiological analysis revealed that the breed wise prevalence was found to be more in Deshi breeds as compared to others, age groups below 6 months were found to be more prone to parvovirus infection and males were mostly infected.

Preadolescent Anxiety: An Epidemiological Study Concerning an Italian Sample of 3,479 Nine-Year-Old Pupils

ERIC Educational Resources Information Center

Nacinovich, Renata; Gadda, Stefania; Maserati, Elisa; Bomba, Monica; Neri, Francesca

2012-01-01

The epidemiology of anxiety traits was examined in a large sample of Italian preadolescent children, and 3,479 Italian nine-year-old subjects were enrolled. Anxious traits were observed in 10.5% of children. No significant gender differences were found, but children of separated couples presented a relative risk for anxious traits that was 50%…

FEASIBILITY OF MATCHING STUDY PARTICIPANT RESIDENCE WITH SPECIFIC WATER UTILITY TRIHALOMETHANE (THM) DATA IN EPIDEMIOLOGIC STUDIES

EPA Science Inventory

Many epidemiologic studies concerning by-products of water disinfection use utility monitoring data to estimate exposure. Use of such data requires linkage of residence location to a specific water utility and associated monitoring data during a given exposure period. The inabil...

Mesotheliomas in Lebanon: Witnessing a Change in Epidemiology.

PubMed

Kattan, Joseph; Eid, Roland; Kourie, Hampig Raphael; Farhat, Fadi; Ghosn, Marwan; Ghorra, Claude; Tomb, Roland

2016-01-01

Mesotheliomas are relatively rare tumors in Lebanon. The only previous study goes back to 14 years ago, when we published epidemiological characteristics of mesotheliomas in Lebanon, showing that the pleural location accounted for the vast majority of cases, with clear evidence of asbestos exposure from the Eternit factory of Chekka region. The objective of this current study was to estimate the incidence of mesothelioma in the past decade and to identify its epidemiological, clinical and therapeutic characteristics, making comparisons with our first study published in 2001. Between 2002 and 2014, patients diagnosed with malignant mesothelioma at Hotel-Dieu de France University Hospital were investigated. Epidemiological data focusing on asbestos exposure history were collected from medical records and interviews with the families. A total of 26 patients were diagnosed with mesothelioma, 21 of which were successfully investigated. The mean age of these 21 patients is 62.5 (19-82). Only 3 (14.29%) are women. 18 (85.71%) were smokers. Among the 21 available mesotheliomas, 15 (71.4%) are pleural, while 5 (23.8%) are peritoneal and 1 (4.8%) pericardial. Only 60% of patients with pleural mesothelioma and 50% of those with an obvious exposure to asbestos lived and/or worked in Chekka region. The mean time of asbestos exposure in patients with mesothelioma is 24.5 (1-50) years and the mean latency is 37.4 (4-61) years. Of the 21 patients, 10 (47.6%) underwent surgery during their treatment, 16 (76.2%) received chemotherapy and 3 (14.3%) received best supportive care. Compared to the previous study (1991-2000), substantial changes in the epidemiology of mesothelioma in Lebanon were observed, such as an increase in peritoneal localizations and a lower correlation with Chekka region asbestos contamination.

Comparison of normal tissue dose calculation methods for epidemiological studies of radiotherapy patients.

PubMed

Mille, Matthew M; Jung, Jae Won; Lee, Choonik; Kuzmin, Gleb A; Lee, Choonsik

2018-06-01

Radiation dosimetry is an essential input for epidemiological studies of radiotherapy patients aimed at quantifying the dose-response relationship of late-term morbidity and mortality. Individualised organ dose must be estimated for all tissues of interest located in-field, near-field, or out-of-field. Whereas conventional measurement approaches are limited to points in water or anthropomorphic phantoms, computational approaches using patient images or human phantoms offer greater flexibility and can provide more detailed three-dimensional dose information. In the current study, we systematically compared four different dose calculation algorithms so that dosimetrists and epidemiologists can better understand the advantages and limitations of the various approaches at their disposal. The four dose calculations algorithms considered were as follows: the (1) Analytical Anisotropic Algorithm (AAA) and (2) Acuros XB algorithm (Acuros XB), as implemented in the Eclipse treatment planning system (TPS); (3) a Monte Carlo radiation transport code, EGSnrc; and (4) an accelerated Monte Carlo code, the x-ray Voxel Monte Carlo (XVMC). The four algorithms were compared in terms of their accuracy and appropriateness in the context of dose reconstruction for epidemiological investigations. Accuracy in peripheral dose was evaluated first by benchmarking the calculated dose profiles against measurements in a homogeneous water phantom. Additional simulations in a heterogeneous cylinder phantom evaluated the performance of the algorithms in the presence of tissue heterogeneity. In general, we found that the algorithms contained within the commercial TPS (AAA and Acuros XB) were fast and accurate in-field or near-field, but not acceptable out-of-field. Therefore, the TPS is best suited for epidemiological studies involving large cohorts and where the organs of interest are located in-field or partially in-field. The EGSnrc and XVMC codes showed excellent agreement with measurements

Consumption of fruit and vegetables reduces risk of pancreatic cancer: evidence from epidemiological studies.

PubMed

Wu, Qi-Jun; Wu, Lang; Zheng, Li-Qiang; Xu, Xin; Ji, Chao; Gong, Ting-Ting

2016-05-01

Observational studies have reported inconsistent results on the association between fruit and vegetable intake and the risk of pancreatic cancer. We carried out a meta-analysis of epidemiological studies to summarize available evidence. We searched PubMed, Scopus, and ISI Web of Science databases for relevant studies published until the end of January 2015. Fixed-effects and random-effects models were used to estimate the summary relative risks (RRs) and 95% confidence intervals (CIs) for the associations between fruit and vegetable intake and the risk of pancreatic cancer. A total of 15 case-control studies, eight prospective studies, and one pooled analysis fulfilled the inclusion criteria. The summary RR for the highest versus the lowest intake was 0.73 (95% CI=0.53-1.00) for fruit and vegetables, 0.73 (95% CI=0.63-0.84) for fruit, and 0.76 (95% CI=0.69-0.83) for vegetables, with significant heterogeneities (I=70.5, 55.7, and 43.0%, respectively). Inverse associations were observed in the stratified analysis by study design, although the results of prospective studies showed borderline significance, with corresponding RR=0.90 (95% CI=0.77-1.05) for fruit and vegetable intake, 0.93 (95% CI=0.83-1.03) for fruit intake, and 0.89 (95% CI=0.80-1.00) for vegetable intake. Besides, significant inverse associations were observed in the majority of other subgroup analyses by study quality, geographic location, exposure assessment method, and adjustment for potential confounders. Findings from the present meta-analysis support that fruit and vegetable intake is associated inversely with the risk of pancreatic cancer. However, study design may play a key role in the observed magnitude of the aforementioned association. Future well-designed prospective studies are warranted to confirm these findings.

Some applications of categorical data analysis to epidemiological studies.

PubMed Central

Grizzle, J E; Koch, G G

1979-01-01

Several examples of categorized data from epidemiological studies are analyzed to illustrate that more informative analysis than tests of independence can be performed by fitting models. All of the analyses fit into a unified conceptual framework that can be performed by weighted least squares. The methods presented show how to calculate point estimate of parameters, asymptotic variances, and asymptotically valid chi 2 tests. The examples presented are analysis of relative risks estimated from several 2 x 2 tables, analysis of selected features of life tables, construction of synthetic life tables from cross-sectional studies, and analysis of dose-response curves. PMID:540590

Foodborne outbreak simulation to teach field epidemiology: the Moroccan Field Epidemiology Training Program.

PubMed

Jroundi, Imane; Belarbi, Abdellatif

2016-11-01

Morocco in 2010 launched a new field epidemiology training program to enhance the skills of health professionals in charge of epidemiological surveillance and to investigate outbreaks; including foodborne diseases that represent a very substantial burden of disease. To apply an active learning method to teach outbreak investigation within a controled environment for field epidemiology trainees program at the Moroccan National school of public Health. A scenario describing digestive symptoms evoking a restaurant-associated foodborne outbreak that would affect the school staff was designed for the residents to investigate, to assess their organizational capacity and application of all stages of epidemiological investigation. Nine Residents applied study design, database management and statistical analysis to investigate the foodborne outbreak, to estimate attack rates, classify cases and controls, to identify the contaminated foods and pathogens and to issue preventive recommendations for the control and the prevention of further transmission. The overall resident's satisfaction of the learning method was 67%. A simulation of an outbreak investigation within an academic setting is an active learning method to be used in the curriculum for introducing the residents on field epidemiology program to the principles and practices of outbreak investigation before their implication in a real situation.

How molecular epidemiology studies can support the National Malaria Control Program in Papua New Guinea.

PubMed

Koepfli, Cristian; Barry, Alyssa; Javati, Sarah; Timinao, Lincoln; Nate, Elma; Mueller, Ivo; Barnadas, Celine

2014-01-01

Papua New Guinea (PNG) is undertaking intensified efforts to control malaria. The National Malaria Control Program aims to reduce the burden of disease by large-scale distribution of insecticide-treated bednets, improved diagnosis and implementation of new treatments. A scientific program monitoring the effect of these interventions, including molecular epidemiology studies, closely accompanies the program. Laboratory assays have been developed in (or transferred to) PNG to measure prevalence of infection and intensity of transmission as well as potential resistance to currently used drugs. These assays help to assess the impact of the National Malaria Control Program, and they reveal a much clearer picture of malaria epidemiology in PNG. In addition, analysis of the geographical clustering of parasites aids in selecting areas where intensified control will be most successful. This paper gives an overview of current research and recently completed studies in the molecular epidemiology of malaria conducted in Papua New Guinea.

The epidemiological modelling of dysthymia: application for the Global Burden of Disease Study 2010.

PubMed

Charlson, Fiona J; Ferrari, Alize J; Flaxman, Abraham D; Whiteford, Harvey A

2013-10-01

In order to capture the differences in burden between the subtypes of depression, the Global Burden of Disease 2010 Study for the first time estimated the burden of dysthymia and major depressive disorder separately from the previously used umbrella term 'unipolar depression'. A global summary of epidemiological parameters are necessary inputs in burden of disease calculations for 21 world regions, males and females and for the year 1990, 2005 and 2010. This paper reports findings from a systematic review of global epidemiological data and the subsequent development of an internally consistent epidemiological model of dysthymia. A systematic search was conducted to identify data sources for the prevalence, incidence, remission and excess-mortality of dysthymia using Medline, PsycINFO and EMBASE electronic databases and grey literature. DisMod-MR, a Bayesian meta-regression tool, was used to check the epidemiological parameters for internal consistency and to predict estimates for world regions with no or few data. The systematic review identified 38 studies meeting inclusion criteria which provided 147 data points for 30 countries in 13 of 21 world regions. Prevalence increases in the early ages, peaking at around 50 years. Females have higher prevalence of dysthymia than males. Global pooled prevalence remained constant across time points at 1.55% (95%CI 1.50-1.60). There was very little regional variation in prevalence estimates. There were eight GBD world regions for which we found no data for which DisMod-MR had to impute estimates. The addition of internally consistent epidemiological estimates by world region, age, sex and year for dysthymia contributed to a more comprehensive estimate of mental health burden in GBD 2010. © 2013 Elsevier B.V. All rights reserved.

Breast Cancer Epidemiology in Puerto Rico

DTIC Science & Technology

2010-06-01

cancer epidemiology. Dr. Rosario took a course on Social Epidemiology at Johns Hopkins Bloomberg School of Public Health Baltimore, MD. June 29 to...July 3, 2009. This course offered an overview of conceptual and methodological approaches relevant to the study of the impact of social factors on...conference call. 2. Training: a. Courses: i. Attended a course on Social Epidemiology at Johns Hopkins Bloomberg School of Public Health

Epidemiological study of multiple sclerosis in La Rioja.

PubMed

Bártulos Iglesias, M; Marzo Sola, M E; Estrella Ruiz, L A; Bravo Anguiano, Y

2015-01-01

Multiple sclerosis is a demyelinating disease that causes severe disability in younger patients. Many epidemiology studies have confirmed a variable prevalence. The objective of this study was to analyse the prevalence of this disease in La Rioja (Spain), using such variables as age and sex; type of progression, initial form of the disease, EDSS and number of relapses; disease-modifying treatment and reasons for treatment withdrawal; personal and family history of cancer; and incidence and mortality. Analysis of patients in La Rioja diagnosed with MS (according to Poser criteria or the 2005 McDonald criteria) during a 10-year period (2001-2011). Data were collected from hospital records, multiple sclerosis associations, and personal records kept by neurologists. The MS prevalence rate in La Rioja is 65 patients/100 000 inhabitants with an incidence rate of 3.5 cases/100 000 residents per year. Relapsing-remitting MS is present in 67.6% of the patient total. Mean age of onset is 20-29 years (range, 12 to 70). Most EDSS scores were mostly ≤ 2. Untreated MS cases account for 47.6% of the total and the most commonly used therapy is interferon. We detected 4 haematological tumours and 7 families with multiple members affected by MS. Prevalence and incidence are similar to those found in other regions Spain. The average age at onset age for primary progressive MS is slightly higher than in other papers (40-49 years). In families with multiple patients, MS may be more aggressive. Disability in these patients remains very severe. We require more epidemiology studies with a variety of data gathering methods to support findings for prevalence obtained in different provinces. Copyright © 2013 Sociedad Española de Neurología. Published by Elsevier España, S.L.U. All rights reserved.

[Genetic, epidemiologic and clinical study of familial prostate cancer].

PubMed

Valéri, Antoine

2002-01-01

Prostate cancer (CaP) is the most frequent cancer among men over 50 and its frequency increases with age. It has become a significant public health problem due to the ageing population. Epidemiologists report familial aggregation in 15 to 25% of cases and inherited susceptibility with autosomal dominant or X-linked model in 5 to 10% of cases. Clinical and biological features of familial CaP remain controversial. To perform: (1) Genetic study of familial Cap (mapping of susceptibility genes), (2) epidemiologic study (prevalence, associated cancers in the genealogy, model of transmission), and clinical study of familial CaP. (I) conducting a nationwide family collection (ProGène study) with 2+ CaP we have performed a genomewide linkage analysis and identified a predisposing locus on 1q42.2-43 named PCaP (Predisposing to Cancer of the Prostate); (II) conducting a systematic genealogic analysis of 691 CaP followed up in 3 University departments of urology (Hospitals of Brest, Paris St Louis and Nancy) we have observed: (1) 14.2% of familial and 3.6% of hereditary CaP, (2) a higher risk of breast cancer in first degree relatives of probands (CaP+) in familial CaP than in sporadic CaP and in early onset CaP (< 55 years) when compared with late onset CaP ([dG]75 years), (3) an autosomal dominant model with brother-brother dependance), (4) the lack of specific clinical or biological feature (except for early onset) in hereditary CaP when compared with sporadic CaP. (1) The mapping of a susceptibility locus will permit the cloning of a predisposing gene on 1q42.2-43, offer the possibility of genetic screening in families at risk and permit genotype/phenotype correlation studies; (2) the transmission model will improve parameteric linkage studies; (3) the lack of distinct specific clinical patterns suggest diagnostic and follow up modalities for familial and hereditary CaP similar to sporadic cancer while encouraging early screening of families at risk, given the earlier

Epidemiology of multiple chronic conditions: an international perspective.

PubMed

Schellevis, François G

2013-01-01

The epidemiology of multimorbidity, or multiple chronic conditions (MCCs), is one of the research priority areas of the U.S. Department of Health and Human Services (HHS) by its Strategic Framework on MCCs. A conceptual model addressing methodological issues leading to a valid measurement of the prevalence rates of MCCs has been developed and applied in descriptive epidemiological studies. Comparing these results with those from prevalence studies performed earlier and in other countries is hampered by methodological limitations. Therefore, this paper aims to put the size and patterns of MCCs in the USA, as established within the HHS Strategic Framework on MCCs, in perspective of the findings on the prevalence of MCCs in other countries. General common trends can be observed: increasing prevalence rates with increasing age, and multimorbidity being the rule rather than the exception at old age. Most frequent combinations of chronic diseases include the most frequently occurring single chronic diseases. New descriptive epidemiological studies will probably not provide new results; therefore, future descriptive studies should focus on the prevalence rates of MCCs in subpopulations, statistical clustering of chronic conditions, and the development of the prevalence rates of MCCs over time. The finding of common trends also indicates the necessary transition to a next phase of MCC research, addressing the quality of care of patients with MCCs from an organizational perspective and with respect to the content of care. Journal of Comorbidity 2013;3:36-40.

Center for Epidemiologic Studies Depression Scale for Children: psychometric testing of the Chinese version.

PubMed

Li, Ho Cheung William; Chung, Oi Kwan Joyce; Ho, Ka Yan

2010-11-01

This paper is a report of psychometric testing of the Chinese version of the Center for Epidemiologic Studies Depression Scale for Children. The availability of a valid and reliable instrument that accurately detects depressive symptoms in children is crucial before any psychological intervention can be appropriately planned and evaluated. There is no such an instrument for Chinese children. A test-retest, within-subjects design was used. A total of 313 primary school students between the ages of 8 and 12 years were invited to participate in the study in 2009. Participants were asked to respond to the Chinese version of the Center for Epidemiologic Studies Depression Scale for Children, short form of the State Anxiety Scale for Children and Rosenberg's Self-Esteem Scale. The internal consistency, content validity and construct validity and test-retest reliability of the Chinese version of the Center for Epidemiologic Studies Depression Scale for Children were assessed. The newly-translated scale demonstrated adequate internal consistency, good content validity and appropriate convergent and discriminant validity. Confirmatory factor analysis added further evidence of the construct validity of the scale. Results suggest that the newly-translated scale can be used as a self-report assessment tool in detecting depressive symptoms of Chinese children aged between 8 and 12 years. © 2010 Blackwell Publishing Ltd.

Epidemiology of psychogenic nonepileptic seizures.

PubMed

Asadi-Pooya, Ali A; Sperling, Michael R

2015-05-01

We critically review the existing literature about the epidemiology (i.e., diagnosis, occurrence, age, gender, comorbidity with epilepsy, associated factors, prognosis, mortality, and cost) of psychogenic nonepileptic seizures (PNES) and provide suggestions for future research. Psychogenic nonepileptic seizures are commonly diagnosed at epilepsy centers. The diagnosis of PNES relies on a multidisciplinary evaluation and is usually based on different combinations of data. Recording a seizure, while under video-EEG monitoring, is the most reliable diagnostic test. However, not all patients present with seizures while under video-EEG monitoring. Furthermore, not all epileptic seizures produce visible changes in the scalp EEG. The incidence of PNES was estimated to be 1.4-4.9/100,000/year in three previous studies, and the prevalence was calculated to be between 2 to 33 per 100,000 in one study, making it a significant neuropsychiatric condition. However, there remains a scarcity of data about the epidemiology of PNES, and extant studies that assessed the epidemiological characteristics of PNES have significant limitations. For example, inconsistencies with regard to the age of patients studied and lack of standardization of the diagnostic criteria are some of the significant limitations among studies. In conclusion, PNES merit further epidemiological and pathophysiological investigation. A more precise definition and clear guidance on standards for the diagnosis might influence the direction of future research. Well-designed prospective population-based studies to clarify the epidemiology of PNES in various parts of the world, including an evaluation of the predisposing, precipitating, and perpetuating factors in cross-cultural comparisons is required. Copyright © 2015 Elsevier Inc. All rights reserved.

Epidemiologic studies of the human microbiome and cancer.

PubMed

Vogtmann, Emily; Goedert, James J

2016-02-02

The human microbiome, which includes the collective genome of all bacteria, archaea, fungi, protists, and viruses found in and on the human body, is altered in many diseases and may substantially affect cancer risk. Previously detected associations of individual bacteria (e.g., Helicobacter pylori), periodontal disease, and inflammation with specific cancers have motivated studies considering the association between the human microbiome and cancer risk. This short review summarises microbiome research, focusing on published epidemiological associations with gastric, oesophageal, hepatobiliary, pancreatic, lung, colorectal, and other cancers. Large, prospective studies of the microbiome that employ multidisciplinary laboratory and analysis methods, as well as rigorous validation of case status, are likely to yield translational opportunities to reduce cancer morbidity and mortality by improving prevention, screening, and treatment.

Epidemiologic studies of the human microbiome and cancer

PubMed Central

Vogtmann, Emily; Goedert, James J

2016-01-01

The human microbiome, which includes the collective genome of all bacteria, archaea, fungi, protists, and viruses found in and on the human body, is altered in many diseases and may substantially affect cancer risk. Previously detected associations of individual bacteria (e.g., Helicobacter pylori), periodontal disease, and inflammation with specific cancers have motivated studies considering the association between the human microbiome and cancer risk. This short review summarises microbiome research, focusing on published epidemiological associations with gastric, oesophageal, hepatobiliary, pancreatic, lung, colorectal, and other cancers. Large, prospective studies of the microbiome that employ multidisciplinary laboratory and analysis methods, as well as rigorous validation of case status, are likely to yield translational opportunities to reduce cancer morbidity and mortality by improving prevention, screening, and treatment. PMID:26730578

The application of epidemiology in aquatic animal health -opportunities and challenges.

PubMed

Peeler, Edmund J; Taylor, Nicholas G H

2011-08-11

Over recent years the growth in aquaculture, accompanied by the emergence of new and transboundary diseases, has stimulated epidemiological studies of aquatic animal diseases. Great potential exists for both observational and theoretical approaches to investigate the processes driving emergence but, to date, compared to terrestrial systems, relatively few studies exist in aquatic animals. Research using risk methods has assessed routes of introduction of aquatic animal pathogens to facilitate safe trade (e.g. import risk analyses) and support biosecurity. Epidemiological studies of risk factors for disease in aquaculture (most notably Atlantic salmon farming) have effectively supported control measures. Methods developed for terrestrial livestock diseases (e.g. risk-based surveillance) could improve the capacity of aquatic animal surveillance systems to detect disease incursions and emergence. The study of disease in wild populations presents many challenges and the judicious use of theoretical models offers some solutions. Models, parameterised from observational studies of host pathogen interactions, have been used to extrapolate estimates of impacts on the individual to the population level. These have proved effective in estimating the likely impact of parasite infections on wild salmonid populations in Switzerland and Canada (where the importance of farmed salmon as a reservoir of infection was investigated). A lack of data is often the key constraint in the application of new approaches to surveillance and modelling. The need for epidemiological approaches to protect aquatic animal health will inevitably increase in the face of the combined challenges of climate change, increasing anthropogenic pressures, limited water sources and the growth in aquaculture.

[Epidemiological study on addictive behaviours during pregnancy in a universitary department].

PubMed

Chassevent-Pajot, A; Guillou-Landréat, M; Grall-Bronnec, M; Wainstein, L; Philippe, H-J; Lombrail, P; Vénisse, J-L

2011-05-01

Epidemiological study on addictive disorders during pregnancy. An epidemiological study about addictive disorders has been led in the maternity of the University Hospital of Nantes in 2008 on a sample of 300 women, just after childbirth. The prevalence of consumption of drugs was assessed on declared consumption of legal and illegal substances and on the Fagerström questionnaire, the AUDIT questionnaire and the CAST questionnaire. Diagnostic of eating disorders was based on DSM IV criteria of mental anorexia and bulimia nervosa. At the beginning of pregnancy, 34% of women used tobacco, 63% alcohol and 8% cannabis. Among the women of the study 0.7% had criteria for mental anorexia, 2.3% for bulimia nervosa and 9% for sub clinic forms. After the first trimester, 22% of women declared using tobacco, 20% alcohol and 3% cannabis. The use of various drugs during pregnancy concerned 6.3% of women, and 38% used at least one drug after the first trimester. The high prevalence of addictive disorders during pregnancy should incite professional of prenatal care to improve their screening methodology and not only when tobacco or alcohol is suspected. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Review of refractory ceramic fiber (RCF) toxicity, epidemiology and occupational exposure.

PubMed

Maxim, L Daniel; Utell, Mark J

2018-02-01

This literature review on refractory ceramic fibers (RCF) summarizes relevant information on manufacturing, processing, applications, occupational exposure, toxicology and epidemiology studies. Rodent toxicology studies conducted in the 1980s showed that RCF caused fibrosis, lung cancer and mesothelioma. Interpretation of these studies was difficult for various reasons (e.g. overload in chronic inhalation bioassays), but spurred the development of a comprehensive product stewardship program under EPA and later OSHA oversight. Epidemiology studies (both morbidity and mortality) were undertaken to learn more about possible health effects resulting from occupational exposure. No chronic animal bioassay studies on RCF have been conducted since the 1980s. The results of the ongoing epidemiology studies confirm that occupational exposure to RCF is associated with the development of pleural plaques and minor decrements in lung function, but no interstitial fibrosis or incremental lung cancer. Evidence supporting a finding that urinary tumors are associated with RCF exposure remains, but is weaker. One reported, but unconfirmed, mesothelioma was found in an individual with prior occupational asbestos exposure. An elevated SMR for leukemia was found, but was absent in the highly exposed group and has not been observed in studies of other mineral fibers. The industry will continue the product stewardship program including the mortality study.

Advances in spatial epidemiology and geographic information systems.

PubMed

Kirby, Russell S; Delmelle, Eric; Eberth, Jan M

2017-01-01

The field of spatial epidemiology has evolved rapidly in the past 2 decades. This study serves as a brief introduction to spatial epidemiology and the use of geographic information systems in applied research in epidemiology. We highlight technical developments and highlight opportunities to apply spatial analytic methods in epidemiologic research, focusing on methodologies involving geocoding, distance estimation, residential mobility, record linkage and data integration, spatial and spatio-temporal clustering, small area estimation, and Bayesian applications to disease mapping. The articles included in this issue incorporate many of these methods into their study designs and analytical frameworks. It is our hope that these studies will spur further development and utilization of spatial analysis and geographic information systems in epidemiologic research. Copyright © 2016 Elsevier Inc. All rights reserved.

[Participation refusal by probands in an epidemiologic long-term study--sociodemographic, clinical and psychometric findings].

PubMed

Franz, M; Schepank, H; Wirth, T; Schellberg, D

1992-11-01

Usually little is known about probands who participated in an epidemiological longitudinal field survey but refused participation in follow-up investigations. For reasons of data protection and on account of the fact that investigative instruments used in longterm field surveys or panel studies are more focused on well defined issues (opinions, attitudes, assessment of behaviors) and less on personality variables, differentiated statements on probands who explicitly refused cooperation can hardly be made. In our epidemiological longitudinal field study on prevalence and course of psychogenic disorders we have a different situation. Within the limits of our study we had the unique opportunity to gain far-reaching information on probands who refused to participate in preceding investigations in regard to sociodemographic, psychometric and clinical variables. The clientele of refusers we present in our paper mainly comprises elderly, married, rather obsessive-compulsive structured, lower-class females. According to our data interactive aspects are equally responsible for reduced cooperativeness. The significance of our findings for the planning and carrying out of epidemiological longitudinal field surveys is discussed.

[Identification and sampling of people with migration background for epidemiological studies in Germany].

PubMed

Reiss, K; Makarova, N; Spallek, J; Zeeb, H; Razum, O

2013-06-01

In 2009, 19.6% of the population of Germany either had migrated themselves or were the offspring of people with migration experience. Migrants differ from the autochthonous German population in terms of health status, health awareness and health behaviour. To further investigate the health situation of migrants in Germany, epidemiological studies are needed. Such studies can employ existing databases which provide detailed information on migration status. Otherwise, onomastic or toponomastic procedures can be applied to identify people with migration background. If migrants have to be recruited into an epidemiological study, this can be done register-based (e. g., data from registration offices or telephone lists), based on residential location (random-route or random-walk procedure), via snowball sampling (e. g., through key persons) or via settings (e. g., school entry examination). An oversampling of people with migration background is not sufficient to avoid systematic bias in the sample due to non-participation. Additional measures have to be taken to increase access and raise participation rates. Personal contacting, multilingual instruments, multilingual interviewers and extensive public relations increase access and willingness to participate. Empirical evidence on 'successful' recruitment strategies for studies with migrants is still lacking in epidemiology and health sciences in Germany. The choice of the recruitment strategy as well as the measures to raise accessibility and willingness to participate depend on the available resources, the research question and the specific migrant target group. © Georg Thieme Verlag KG Stuttgart · New York.

QMRA as a compliment to epidemiologic studies estimating bather risk at recreational beaches

EPA Science Inventory

The US EPA and WHO have set recreational water quality standards based on epidemiologic studies to protect human health at beaches. These studies have largely been limited to sewage-impacted sites and resources are unlikely to be available to assess the myriad of other impacted ...

Horizontal study of vaccinia virus infections in an endemic area: epidemiologic, phylogenetic and economic aspects.

PubMed

Assis, Felipe L; Franco-Luiz, Ana Paula M; Paim, Luis M; Oliveira, Graziele P; Pereira, Alexandre F; de Almeida, Gabriel M F; Figueiredo, Leandra B; Tanus, Adriano; Trindade, Giliane S; Ferreira, Paulo P; Kroon, Erna G; Abrahão, Jônatas S

2015-11-01

Vaccinia virus (VACV), the etiological agent of bovine vaccinia (BV), is widespread in Brazil and present in most of the milk-producing regions. We conducted a horizontal study of BV in Bahia, a state of Brazil in which the production of milk is increasing. During 2011, human and bovine clinical samples were collected during outbreaks for BV diagnosis, virus isolation and molecular analysis. We collected data for epidemiological inferences. Vaccinia virus was detected in 87.7% of the analyzed outbreaks, highlighting the effective circulation of VACV in Bahia. The molecular data showed the spreading of group 1 Brazilian VACV to Bahia. We observed a seasonal profile of BV, with its peak in the drier and cooler season. Manual milking was observed in 96 % of the visited properties, showing its importance to viral spread in herds. Under-notification of BV, ineffective animal trade surveillance, and bad milking practices have contributed to the spread of VACV in Brazil.

Environmental Epidemiology Program

Science.gov Websites

accessible with JavaScript activated. Utah Department of Health Bureau of Epidemiology Environmental Epidemiology Program (EEP) The Environmental Epidemiology Program strives to improve the health of Utah residents through science-based environmental health policy and by empowering citizens with knowledge about

Radiation epidemiology: Past and present

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

Boice, J.D. Jr.

1997-03-01

Major advancements in radiation epidemiology have occurred during the last several years in studies of atomic bomb survivors, patients given medical radiation, and radiation workers, including underground miners. Risks associated with the Chernobyl accident, indoor radon and childhood exposure to I-131 have yet to be elucidated. Situations in the former Soviet Union around Chelyabinsk, a nuclear installation in the southern Urals, and in the Altai, which received radioactive fallout from weapons testing at Semipalatinsk, Kazakhstan, have the potential to provide information on the effects of chronic radiation exposure. Since Roentgen`s discovery of x-rays just 100 years ago, a tremendous amountmore » of knowledge has been accumulated about human health effects following irradiation. The 1994 UNSCEAR report contains the latest compilation and synthesis of radiation epidemiology. This overview will cover epidemiology from a radiation perspective. The different types of study methodologies will be described, followed by a kaleidoscope coverage of past and present studies; ending with some remaining questions in radiation epidemiology. This should set the stage for future chapters, and stimulate thinking about implications of the new data on radiation cancer risks.« less

Erectile dysfunction--an observable marker of diabetes mellitus? A large national epidemiological study.

PubMed

Sun, Peter; Cameron, Ann; Seftel, Allen; Shabsigh, Ridwan; Niederberger, Craig; Guay, Andre

2006-09-01

We examined whether men with erectile dysfunction are more likely to have diabetes mellitus than men without erectile dysfunction, and whether erectile dysfunction can be used as an observable early marker of diabetes mellitus. Using a nationally representative managed care claims database from 51 health plans and 28 million members in the United States, we conducted a retrospective cohort study to compare the prevalence rates of diabetes mellitus between men with erectile dysfunction (285,436) and men without erectile dysfunction (1,584,230) during 1995 to 2001. Logistic regression models were used to isolate the effect of erectile dysfunction on the likelihood of having diabetes mellitus with adjustment for age, region and 7 concurrent diseases. The diabetes mellitus prevalence rates were 20.0% in men with erectile dysfunction and 7.5% in men without erectile dysfunction. With adjustment for age, region and concurrent diseases, the odds ratio of having diabetes mellitus between men with erectile dysfunction and without erectile dysfunction was 1.60 (p <0.0001). With adjustment for regions and concurrent diseases, the age specific odds ratios ranged from 2.94 (p <0.0001, age 26 to 35) to 1.05 (p = 0.1717, age 76 to 85). Men with erectile dysfunction were more than twice as likely to have diabetes mellitus as men without erectile dysfunction. Erectile dysfunction is an observable marker of diabetes mellitus, strongly so for men 45 years old or younger and likely for men 46 to 65 years old, but it is not a marker for men older than 66 years.

Red and Processed Meat Intake Is Associated with Higher Gastric Cancer Risk: A Meta-Analysis of Epidemiological Observational Studies

PubMed Central

Zhang, Chi; Zhu, Chen; Tao, Guangzhou; Zhao, Lianjun; Tang, Shaowen; Shu, Zheng; Cai, Jing; Dai, Shengbin; Qin, Qin; Xu, Liping; Cheng, Hongyan; Sun, Xinchen

2013-01-01

Background Red and processed meat was concluded as a limited-suggestive risk factor of gastric cancer by the World Cancer Research Fund. However, recent epidemiological studies have yielded inconclusive results. Methods We searched Medline, EMBASE, and the Cochrane Library from their inception to April 2013 for both cohort and case-control studies which assessed the association between red and/or processed meat intake and gastric cancer risk. Study-specific relative risk estimates were polled by random-effect or fixed-effect models. Results Twelve cohort and thirty case-control studies were included in the meta-analysis. Significant associations were found between both red (RR: 1.45, 95% CI: 1.22–1.73) and processed (RR: 1.45, 95% CI: 1.26–1.65) meat intake and gastric cancer risk generally. Positive findings were also existed in the items of beef (RR: 1.28, 95% CI: 1.04–1.57), bacon (RR: 1.37, 95% CI: 1.17–1.61), ham (RR: 1.44, 95% CI: 1.00–2.06), and sausage (RR: 1.33, 95% CI: 1.16–1.52). When conducted by study design, the association was significant in case-control studies (RR: 1.63, 95% CI: 1.33–1.99) but not in cohort studies (RR: 1.02, 95% CI: 0.90–1.17) for red meat. Increased relative risks were seen in high-quality, adenocarcinoma, cardia and European-population studies for red meat. And most subgroup analysis confirmed the significant association between processed meat intake and gastric cancer risk. Conclusions Our findings indicate that consumption of red and/or processed meat contributes to increased gastric cancer risk. However, further investigation is needed to confirm the association, especially for red meat. PMID:23967140

A pilot study: research poster presentations as an educational tool for undergraduate epidemiology students.

PubMed

Deonandan, Raywat; Gomes, James; Lavigne, Eric; Dinh, Thy; Blanchard, Robert

2013-01-01

Students in a fourth year epidemiology course were surveyed after participating in a formal Science Research Day in which they presented original research, in poster form, to be judged by scientists from the community. Of 276 participating students, 80 (29%) responded to the study survey. As a result, 19% of respondents were more likely to pursue a career in science, and 27.5% were more likely to pursue a career in epidemiology. Only one respondent reported being less likely to pursue a science career, while seven were less likely to pursue epidemiology. A majority of respondents felt that the poster experience was on par with, or superior to, a comparable research paper, in terms of both educational appeal and enjoyment. Mandatory, formal poster presentations are an innovative format for teaching advanced health sciences, and may more accurately reflect the realities of a science career than do more traditional educational formats.

Workplace exposure to passive smoking and risk of cardiovascular disease: summary of epidemiologic studies.

PubMed Central

Kawachi, I; Colditz, G A

1999-01-01

We reviewed the published epidemiologic studies addressing the relationship between workplace exposure to environmental tobacco smoke (ETS) and cardiovascular disease risk in three case-control studies and three cohort studies. Although the point estimates of risk for cardiovascular disease exceeded 1.0 in five of six studies, none of the relative risks was statistically significant because of the small number of cardiovascular end points occurring in individual studies. In common with most epidemiologic investigations of the health risks of ETS, none of the workplace studies included independent biochemical validation of ETS exposure. In contrast to the evidence on increased cardiovascular disease risk from exposure to spousal ETS, studies of ETS exposure in the workplace are still sparse and inconclusive. Conversely, there is no biologically plausible reason to believe that the hazards of ETS exposure that have been demonstrated in the home should not also apply to the workplace. PMID:10592141

Development of a systematic observation protocol of physical exposure of the back: a preliminary study.

PubMed

Tousignant, M; Tougas, G; Rossignol, M; Goulet, L

2002-04-01

At present there is no systematic observation protocol for the assessment of the multi-factorial aspects of physical exposure related to the back used within the constraints of occupational epidemiological research. In this context, a new preliminary systematic observation protocol is proposed to assess exposure to physical loading of the back using nine categories of physical risk factors: the SOPE back protocol. The objective of this study was to investigate whether the new protocol can correctly identify the level of exposure related to measured physical loading of the back. The subjects of this closed cohort study were 451 manual workers at a natural gas distribution company. The assessment of exposure was made with the protocol using groups with different job titles. The workers were followed for a 2 yr period to establish the risk of a new occurrence of complete disability related to the back (NOCD back injury) in each job grouping. Based on the median of the total scores derived from the protocol, two levels of exposure were identified (high and low). Taking into account the limitations of this study, the protocol in development may be a good tool to establish two levels of exposure to physical loading of the back in large epidemiological studies of occupational low back pain. Further research is needed to replicate these results with larger samples and to test the reliability and predictive validity of the protocol.

The Intersection of HPV Epidemiology, Genomics and Mechanistic Studies of HPV-Mediated Carcinogenesis.

PubMed

Mirabello, Lisa; Clarke, Megan A; Nelson, Chase W; Dean, Michael; Wentzensen, Nicolas; Yeager, Meredith; Cullen, Michael; Boland, Joseph F; Schiffman, Mark; Burk, Robert D

2018-02-13

Of the ~60 human papillomavirus (HPV) genotypes that infect the cervicovaginal epithelium, only 12-13 "high-risk" types are well-established as causing cervical cancer, with HPV16 accounting for over half of all cases worldwide. While HPV16 is the most important carcinogenic type, variants of HPV16 can differ in their carcinogenicity by 10-fold or more in epidemiologic studies. Strong genotype-phenotype associations embedded in the small 8-kb HPV16 genome motivate molecular studies to understand the underlying molecular mechanisms. Understanding the mechanisms of HPV genomic findings is complicated by the linkage of HPV genome variants. A panel of experts in various disciplines gathered on 21 November 2016 to discuss the interdisciplinary science of HPV oncogenesis. Here, we summarize the discussion of the complexity of the viral-host interaction and highlight important next steps for selected applied basic laboratory studies guided by epidemiological genomic findings.

Pesticide poisoning in Chitwan, Nepal: a descriptive epidemiological study.

PubMed

Gyenwali, Deepak; Vaidya, Abhinav; Tiwari, Sundar; Khatiwada, Prakash; Lamsal, Daya Ram; Giri, Shrikrishana

2017-07-03

Globally, there is a growing concern over pesticides use, which has been linked to self-harm and suicide. However, there is paucity of research on the epidemiology of pesticides poisoning in Nepal. This study is aimed at assessing epidemiological features of pesticides poisoning among hospital-admitted cases in selected hospitals of Chitwan District of Nepal. A hospital-based quantitative study was carried out in four major hospitals of Chitwan District. Information on all pesticides poisoning cases between April 1 and December 31, 2015, was recorded by using a Pesticides Exposure Record (PER) form. A total of 439 acute pesticides poisoning cases from 12 districts including Chitwan and adjoining districts attended the hospitals during the 9-month-long study period. A majority of the poisoned subjects deliberately used pesticides (89.5%) for attempted suicide. The total incidence rate was 62.67/100000 population per year. Higher annual incidence rates were found among young adults (111.66/100000 population), women (77.53/100000 population) and individuals from Dalit ethnic groups (98.22/100000 population). Pesticides responsible for poisoning were mostly insecticides (58.0%) and rodenticides (20.8%). The most used chemicals were organophosphates (37.3%) and pyrethroids (36.7%). Of the total cases, 98.6% were hospitalized, with intensive care required for 41.3%. The case fatality rate among admitted cases was 3.8%. This study has indicated that young adults, females and socially disadvantaged ethnic groups are at a higher risk of pesticides poisoning. Pesticides are mostly misused intentionally as an easy means for committing suicide. It is recommended that the supply of pesticides be properly regulated to prevent easy accessibility and misuse. A population-based study is warranted to reveal the actual problem of pesticides exposure and intoxication in the community.

Principled Approaches to Missing Data in Epidemiologic Studies

PubMed Central

Perkins, Neil J; Cole, Stephen R; Harel, Ofer; Tchetgen Tchetgen, Eric J; Sun, BaoLuo; Mitchell, Emily M; Schisterman, Enrique F

2018-01-01

Abstract Principled methods with which to appropriately analyze missing data have long existed; however, broad implementation of these methods remains challenging. In this and 2 companion papers (Am J Epidemiol. 2018;187(3):576–584 and Am J Epidemiol. 2018;187(3):585–591), we discuss issues pertaining to missing data in the epidemiologic literature. We provide details regarding missing-data mechanisms and nomenclature and encourage the conduct of principled analyses through a detailed comparison of multiple imputation and inverse probability weighting. Data from the Collaborative Perinatal Project, a multisite US study conducted from 1959 to 1974, are used to create a masked data-analytical challenge with missing data induced by known mechanisms. We illustrate the deleterious effects of missing data with naive methods and show how principled methods can sometimes mitigate such effects. For example, when data were missing at random, naive methods showed a spurious protective effect of smoking on the risk of spontaneous abortion (odds ratio (OR) = 0.43, 95% confidence interval (CI): 0.19, 0.93), while implementation of principled methods multiple imputation (OR = 1.30, 95% CI: 0.95, 1.77) or augmented inverse probability weighting (OR = 1.40, 95% CI: 1.00, 1.97) provided estimates closer to the “true” full-data effect (OR = 1.31, 95% CI: 1.05, 1.64). We call for greater acknowledgement of and attention to missing data and for the broad use of principled missing-data methods in epidemiologic research. PMID:29165572

Principled Approaches to Missing Data in Epidemiologic Studies.

PubMed

Perkins, Neil J; Cole, Stephen R; Harel, Ofer; Tchetgen Tchetgen, Eric J; Sun, BaoLuo; Mitchell, Emily M; Schisterman, Enrique F

2018-03-01

Principled methods with which to appropriately analyze missing data have long existed; however, broad implementation of these methods remains challenging. In this and 2 companion papers (Am J Epidemiol. 2018;187(3):576-584 and Am J Epidemiol. 2018;187(3):585-591), we discuss issues pertaining to missing data in the epidemiologic literature. We provide details regarding missing-data mechanisms and nomenclature and encourage the conduct of principled analyses through a detailed comparison of multiple imputation and inverse probability weighting. Data from the Collaborative Perinatal Project, a multisite US study conducted from 1959 to 1974, are used to create a masked data-analytical challenge with missing data induced by known mechanisms. We illustrate the deleterious effects of missing data with naive methods and show how principled methods can sometimes mitigate such effects. For example, when data were missing at random, naive methods showed a spurious protective effect of smoking on the risk of spontaneous abortion (odds ratio (OR) = 0.43, 95% confidence interval (CI): 0.19, 0.93), while implementation of principled methods multiple imputation (OR = 1.30, 95% CI: 0.95, 1.77) or augmented inverse probability weighting (OR = 1.40, 95% CI: 1.00, 1.97) provided estimates closer to the "true" full-data effect (OR = 1.31, 95% CI: 1.05, 1.64). We call for greater acknowledgement of and attention to missing data and for the broad use of principled missing-data methods in epidemiologic research.

Review of epidemiological studies searching for a relationship between onchocerciasis and epilepsy.

PubMed

Druet-Cabanac, M; Boussinesq, M; Dongmo, L; Farnarier, G; Bouteille, B; Preux, P M

2004-01-01

A review and a meta-analysis of the available epidemiological literature for evidence of an association between onchocerciasis infection and epilepsy were carried out. We used EMBASE (1974-2002), MEDLINE (1966-2002), and PASCAL (1987-2002) databases and relevant journals and bibliographies. We limited our analysis to the epidemiological studies, where the status regarding onchocerciasis infection and epilepsy was available for each subject. Nine African studies were included. The common relative risk estimated by the random-effects model was 1.21 (95% CI 0.99-1.47; p = 0.06). The meta-analysis did not show any difference according to the onchocerciasis endemicity level and the African areas. Our results do not allow to conclude for an association between Onchocerca volvulus infection and epilepsy. However, the results are nearly significant. Further research is needed in this neglected subject, in particular for the better understanding of the neurological pathogenicity in onchocerciasis. Copyright 2004 S. Karger AG, Basel

Cancer Epidemiology Cohorts

Cancer.gov

Cohort studies are fundamental for epidemiological research by helping researchers better understand the etiology of cancer and provide insights into the key determinants of this disease and its outcomes.

Molecular markers in the epidemiology and diagnosis of coccidioidomycosis.

PubMed

Duarte-Escalante, Esperanza; Frías-De-León, María Guadalupe; Zúñiga, Gerardo; Martínez-Herrera, Erick; Acosta-Altamirano, Gustavo; Reyes-Montes, María Del Rocío

2014-01-01

The prevalence of coccidioidomycosis in endemic areas has been observed to increase daily. To understand the causes of the spread of the disease and design strategies for fungal detection in clinical and environmental samples, scientists have resorted to molecular tools that allow fungal detection in a natural environment, reliable identification in clinical cases and the study of biological characteristics, such as reproductive and genetic structure, demographic history and diversification. We conducted a review of the most important molecular markers in the epidemiology of Coccidioides spp. and the diagnosis of coccidioidomycosis. A literature search was performed for scientific publications concerning the application of molecular tools for the epidemiology and diagnosis of coccidioidomycosis. The use of molecular markers in the epidemiological study and diagnosis of coccidioidomycosis has allowed for the typing of Coccidioides spp. isolates, improved understanding of their mode of reproduction, genetic variation and speciation and resulted in the development specific, rapid and sensitive strategies for detecting the fungus in environmental and clinical samples. Molecular markers have revealed genetic variability in Coccidioides spp. This finding influences changes in the epidemiology of coccidioidomycosis, such as the emergence of more virulent or antifungal resistant genotypes. Furthermore, the molecular markers currently used to identify Coccidioides immitis and Coccidioides posadasii are specific and sensitive. However, they must be validated to determine their application in diagnosis. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012). Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

Air pollution and health in Sri Lanka: a review of epidemiologic studies.

PubMed

Nandasena, Yatagama Lokuge S; Wickremasinghe, Ananda R; Sathiakumar, Nalini

2010-06-02

Air pollution is increasingly documented as a threat to public health in most developing countries. Evaluation of current air quality levels, regulatory standards and scientific literature on outdoor and indoor air pollution, and health effects are important to identify the burden, develop and implement interventions and to fill knowledge gaps in Sri Lanka. PUBMED and Medline databases, local journals and conference proceedings were searched for epidemiologic studies pertaining to air pollution and health effects in Sri Lanka. All the studies pertaining to air pollution and health effects were considered. Sixteen studies investigated the association between exposure to ambient or indoor air pollution (IAP) and various health outcomes ranging from respiratory symptoms, low birth weight and lung cancers. Of the sixteen, three used a case control design. Half of the studies collected exposure data only through questionnaires. There were positive associations between air pollution and adverse health effects in all studies. Methodological limitations in most of the studies resulted in poor quantification of risk estimates. A limited number of epidemiological studies in Sri Lanka have investigated the health effects of air pollution. Based on findings of studies and reported air quality levels, air pollution may be considered a neglected public health problem in Sri Lanka.

Designing Epidemiology Studies to Determine the Incidence and Prevalence of Encapsulating Peritoneal Sclerosis (EPS).

PubMed

Nitsch, Dorothea; Davenport, Andrew

2015-12-01

The reported incidence and prevalence of encapsulating peritoneal sclerosis (EPS) varies markedly between North America, Europe, Japan, and Australia. Although this could reflect differences in clinical practice patterns and access to transplantation as there is no current test for early detection, and some patients may present many years after discontinuation of peritoneal dialysis (PD), there are concerns about under-reporting, particularly for those with milder forms. Currently, only PD vintage has been identified as a significant risk factor for developing EPS, although some patients can develop EPS within months of starting PD. As such, there is a need for epidemiological studies to determine the incidence and prevalence of EPS to allow for patient education and counselling in terms of dialysis modality choice and length of treatment. In addition, carefully designed epidemiological studies could potentially allow for the identification of risk factors and bio-markers that could then be used to identify patients at increased risk of developing EPS in the future. Typically, studies to date have been underpowered with inadequate longitudinal follow-up. We review the different types of epidemiological studies and provide information as to the number of patients to be recruited and the duration of follow-up required to determine the incidence and prevalence of EPS. Copyright © 2015 International Society for Peritoneal Dialysis.

Epidemiological studies in incidence, prevalence, mortality, and comorbidity of the rheumatic diseases

PubMed Central

Gabriel, Sherine E; Michaud, Kaleb

2009-01-01

Epidemiology is the study of the distribution and determinants of disease in human populations. Over the past decade there has been considerable progress in our understanding of the fundamental descriptive epidemiology (levels of disease frequency: incidence and prevalence, comorbidity, mortality, trends over time, geographic distributions, and clinical characteristics) of the rheumatic diseases. This progress is reviewed for the following major rheumatic diseases: rheumatoid arthritis (RA), juvenile rheumatoid arthritis, psoriatic arthritis, osteoarthritis, systemic lupus erythematosus, giant cell arteritis, polymyalgia rheumatica, gout, Sjögren's syndrome, and ankylosing spondylitis. These findings demonstrate the dynamic nature of the incidence and prevalence of these conditions – a reflection of the impact of genetic and environmental factors. The past decade has also brought new insights regarding the comorbidity associated with rheumatic diseases. Strong evidence now shows that persons with RA are at a high risk for developing several comorbid disorders, that these conditions may have atypical features and thus may be difficult to diagnose, and that persons with RA experience poorer outcomes after comorbidity compared with the general population. Taken together, these findings underscore the complexity of the rheumatic diseases and highlight the key role of epidemiological research in understanding these intriguing conditions. PMID:19519924

Childhood Brain Tumor Epidemiology: A Brain Tumor Epidemiology Consortium Review

PubMed Central

Johnson, Kimberly J.; Cullen, Jennifer; Barnholtz-Sloan, Jill S.; Ostrom, Quinn T.; Langer, Chelsea E.; Turner, Michelle C.; McKean-Cowdin, Roberta; Fisher, James L.; Lupo, Philip J.; Partap, Sonia; Schwartzbaum, Judith A.; Scheurer, Michael E.

2014-01-01

Childhood brain tumors are the most common pediatric solid tumor and include several histological subtypes. Although progress has been made in improving survival rates for some subtypes, understanding of risk factors for childhood brain tumors remains limited to a few genetic syndromes and ionizing radiation to the head and neck. In this report, we review descriptive and analytical epidemiology childhood brain tumor studies from the past decade and highlight priority areas for future epidemiology investigations and methodological work that is needed to advance our understanding of childhood brain tumor causes. Specifically, we summarize the results of a review of studies published since 2004 that have analyzed incidence and survival in different international regions and that have examined potential genetic, immune system, developmental and birth characteristics, and environmental risk factors. PMID:25192704

[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.

Epidemiology of Postherpetic Neuralgia in Korea: An Electronic Population Health Insurance System Based Study.

PubMed

Hong, Myong-Joo; Kim, Yeon-Dong; Cheong, Yong-Kwan; Park, Seon-Jeong; Choi, Seung-Won; Hong, Hyon-Joo

2016-04-01

Postherpetic neuralgia (PHN) is a disease entity defined as persistent pain after the acute pain of herpes zoster gradually resolves. It is associated with impaired daily activities, resulting in reduced quality of life. General epidemiological data on PHN is necessary for the effective management. However, data on the epidemiology of PHN in Korea is lacking. The aim of this study was to evaluate the epidemiological features of PHN in the general population.We used population-based medical data for 51,448,491 subscribers to the Health Insurance Service in the year of 2013 to analyze of PHN epidemiology in Korea, such as the incidence, regional distribution, seasonal variation, and healthcare resource utilization. Total number of patients and medical cost on PHN were analyzed from 2009 to 2013.Findings indicate that the incidence of PHN in Korea was 2.5 per 1000 person-years, which was strongly correlated with age and sex. There were no differences in seasonal variation or regional distribution. The medical cost increased steadily over the study period. When admitted to general hospitals, patients with PHN were mainly managed in the dermatology and anesthesiology departments.The incidence and prevalence rates of PHN in Koreans appear to be considerably higher compared to those in western populations, while the sex and age predisposition was similar. Considering that the pain associated with PHN can have a marked impact on a patient's quality of life resulting in a medicosocial economic burden, anesthesiology physicians have an important role in primary care in Korea. Future research on the cost-effectiveness of the management of PHN is needed.

About the Epidemiology and Genomics Research Program

Cancer.gov

Epidemiology is the scientific study of the causes and distribution of disease in populations. NCI-funded epidemiology research is conducted through research at institutions in the United States and internationally.

Multi-agent systems in epidemiology: a first step for computational biology in the study of vector-borne disease transmission.

PubMed

Roche, Benjamin; Guégan, Jean-François; Bousquet, François

2008-10-15

Computational biology is often associated with genetic or genomic studies only. However, thanks to the increase of computational resources, computational models are appreciated as useful tools in many other scientific fields. Such modeling systems are particularly relevant for the study of complex systems, like the epidemiology of emerging infectious diseases. So far, mathematical models remain the main tool for the epidemiological and ecological analysis of infectious diseases, with SIR models could be seen as an implicit standard in epidemiology. Unfortunately, these models are based on differential equations and, therefore, can become very rapidly unmanageable due to the too many parameters which need to be taken into consideration. For instance, in the case of zoonotic and vector-borne diseases in wildlife many different potential host species could be involved in the life-cycle of disease transmission, and SIR models might not be the most suitable tool to truly capture the overall disease circulation within that environment. This limitation underlines the necessity to develop a standard spatial model that can cope with the transmission of disease in realistic ecosystems. Computational biology may prove to be flexible enough to take into account the natural complexity observed in both natural and man-made ecosystems. In this paper, we propose a new computational model to study the transmission of infectious diseases in a spatially explicit context. We developed a multi-agent system model for vector-borne disease transmission in a realistic spatial environment. Here we describe in detail the general behavior of this model that we hope will become a standard reference for the study of vector-borne disease transmission in wildlife. To conclude, we show how this simple model could be easily adapted and modified to be used as a common framework for further research developments in this field.

The epidemiology of dizziness and vertigo.

PubMed

Neuhauser, H K

2016-01-01

This chapter gives an overview of the epidemiology of dizziness, vertigo, and imbalance, and of specific vestibular disorders. In the last decade, population-based epidemiologic studies have complemented previous publications from specialized settings and provided evidence for the high burden of dizziness and vertigo in the community. Dizziness (including vertigo) affects about 15% to over 20% of adults yearly in large population-based studies. Vestibular vertigo accounts for about a quarter of dizziness complaints and has a 12-month prevalence of 5% and an annual incidence of 1.4%. Its prevalence rises with age and is about two to three times higher in women than in men. Imbalance has been increasingly studied as a highly prevalent complaint particularly affecting healthy aging. Studies have documented the high prevalence of benign paroxysmal positional vertigo (BPPV) and vestibular migraine (VM), as well as of comorbid anxiety at the population level. BPPV and VM are largely underdiagnosed, while Menière's disease, which is about 10 times less frequent than BPPV, appears to be overdiagnosed. Risk factor research is only at its beginning, but has provided some interesting observations, such as the consistent association of vertigo and migraine, which has greatly contributed to the recognition of VM as a distinct vestibular syndrome. © 2016 Elsevier B.V. All rights reserved.

Comprehensive personal RF-EMF exposure map and its potential use in epidemiological studies.

PubMed

Gonzalez-Rubio, Jesus; Najera, Alberto; Arribas, Enrique

2016-08-01

In recent years, numerous epidemiological studies, which deal with the potential effects of mobile phone antennas on health, have almost exclusively focused on their distance to mobile phone base stations. Although it is known that this is not the best approach to the problem, this situation occurs due to the numerous difficulties when determining the personal exposure to the radiofrequency electromagnetic fields (RF-EMF). However, due to the rise of personal exposimeters, the evolution of spatial statistics, the development of geographical information systems and the use of powerful software, new alternatives are available to deal with these epidemiological studies and thus overcome the aforementioned difficulties. Using these tools, this paper presents a lattice map of personal RF-EMF exposure from exterior mobile phone base stations, covering the entire 110 administrative regions in the city of Albacete (Spain). For this purpose, we used a personal exposimeter, Satimo EME Spy 140 model, performing measurements every 4s The exposimeter was located inside the plastic basket of a bicycle, whose versatility permitted the access to all the zones of the city. Once the exposure map was prepared, its relation with the known antenna locations was studied. The 64 mobile telephone antennas of the city were also georeferenced; the randomness of both variables (exposure and antennas) were studied by means of the Moran's I test. Results showed that the distribution of the antennas follows a grouped pattern (p<0.001), while the distribution of the average exposure values have a random distribution (p=0.618). In addition, we showed two Spearman correlation studies: the first between the average exposure values and the number of mobile telephone antennas per administrative region, and the second, also considering the antennas of the neighbouring regions. No substantial correlation was detected in either of the two cases. This study also reveals the weaknesses of the

Causality and causal inference in epidemiology: the need for a pluralistic approach.

PubMed

Vandenbroucke, Jan P; Broadbent, Alex; Pearce, Neil

2016-12-01

Causal inference based on a restricted version of the potential outcomes approach reasoning is assuming an increasingly prominent place in the teaching and practice of epidemiology. The proposed concepts and methods are useful for particular problems, but it would be of concern if the theory and practice of the complete field of epidemiology were to become restricted to this single approach to causal inference. Our concerns are that this theory restricts the questions that epidemiologists may ask and the study designs that they may consider. It also restricts the evidence that may be considered acceptable to assess causality, and thereby the evidence that may be considered acceptable for scientific and public health decision making. These restrictions are based on a particular conceptual framework for thinking about causality. In Section 1, we describe the characteristics of the restricted potential outcomes approach (RPOA) and show that there is a methodological movement which advocates these principles, not just for solving particular problems, but as ideals for which epidemiology as a whole should strive. In Section 2, we seek to show that the limitation of epidemiology to one particular view of the nature of causality is problematic. In Section 3, we argue that the RPOA is also problematic with regard to the assessment of causality. We argue that it threatens to restrict study design choice, to wrongly discredit the results of types of observational studies that have been very useful in the past and to damage the teaching of epidemiological reasoning. Finally, in Section 4 we set out what we regard as a more reasonable 'working hypothesis' as to the nature of causality and its assessment: pragmatic pluralism. © The Author 2016. Published by Oxford University Press on behalf of the International Epidemiological Association.

Sero-epidemiological study of Lyme disease among high-risk population groups in eastern Slovakia.

PubMed

Zákutná, Ľubica; Dorko, Erik; Mattová, Eva; Rimárová, Kvetoslava

2015-01-01

IIntroduction and objective. The aim of the presented cross-sectional sero-epidemiological study was to determine the current presence of antibodies against B. burgdorferi s.l. in the high-risk groups of the Slovak population, and to identify potential risk factors to LB infections. A group of 277 agricultural and forestry workers - persons with frequent stay in the countryside and employees of State Border and Customs Police - from years 2011-2012 in the Eastern Slovakia were examined in order to assess the seroprevalence of anti-Borrelia antibodies. Sera were screened by commercial enzyme-linked immunosorbent assay (ELISA). The study subjects completed a questionnaires with general demographic, epidemiological and clinical data. The results were evaluated statistically. A 25.3% presence of positive and 8.7% presence of borderline IgG antibodies was detected in all investigated groups. The seroprevalence of B. burgdorferi s.l. was significantly higher (P<0.05) among the agricultural and forestry workers when compared to employees of State Border and Customs Police. Higher seropositivity was observed in older subjects over 30 years of age (P=0.004) than those who were younger, and also in males (P=0.045). A significant number of persons with rheumatologic conditions was statistically higher (P=0.020) in the group with seropositivity than in the group with seronegativity. The presented study confirms the higher risk of Borrelia infection in individuals with frequent exposure to ticks in eastern Slovakia. The seropositivity tests confirmed the highest seropositivity in agriculture and forestry workers, middle positivity was confirmed among other sector workers, and lowest positivity in policemen and employees of the Customs and Border Inspection. The outputs also simultaneously filling the gap of missing seroprevalence data among these exposed groups.

Global epidemiology of podoconiosis: A systematic review

PubMed Central

Trueba, Mei L.; Newport, Melanie J.; Davey, Gail

2018-01-01

Background Podoconiosis is one of the few diseases that could potentially be eliminated within one generation. Nonetheless, the global distribution of the disease remains largely unknown. The global atlas of podoconiosis was conceived to define the epidemiology and distribution of podoconiosis through dedicated surveys and assembling the available epidemiological data. Methods We have synthesized the published literature on the epidemiology of podoconiosis. Through systematic searches in SCOPUS and MEDLINE from inception to February 14, 2018, we identified observational and population-based studies reporting podoconiosis. To establish existence of podoconiosis, we used case reports and presence data. For a study to be included in the prevalence synthesis, it needed to be a population-based survey that involved all residents within a specific area. Studies that did not report original data were excluded. We undertook descriptive analyses of the extracted data. This study is registered with PROSPERO, number CRD42018084959. Results We identified 3,260 records, of which 27 studies met the inclusion criteria. Podoconiosis was described to exist or be endemic in 32 countries, 18 from the African Region, 3 from Asia and 11 from Latin America. Overall, podoconiosis prevalence ranged from 0·10% to 8.08%, was highest in the African region, and was substantially higher in adults than in children and adolescents. The highest reported prevalence values were in Africa (8.08% in Cameroon, 7.45% in Ethiopia, 4.52% in Uganda, 3.87% in Kenya and 2.51% in Tanzania). In India, a single prevalence of 0.21% was recorded from Manipur, Mizoram and Rajasthan states. None of the Latin American countries reported prevalence data. Conclusion Our data suggest that podoconiosis is more widespread in the African Region than in the rest of the regions, although this could be related to the fact that most podoconiosis epidemiological research has been focused in the African continent. The

Global epidemiology of podoconiosis: A systematic review.

PubMed

Deribe, Kebede; Cano, Jorge; Trueba, Mei L; Newport, Melanie J; Davey, Gail

2018-03-01

Podoconiosis is one of the few diseases that could potentially be eliminated within one generation. Nonetheless, the global distribution of the disease remains largely unknown. The global atlas of podoconiosis was conceived to define the epidemiology and distribution of podoconiosis through dedicated surveys and assembling the available epidemiological data. We have synthesized the published literature on the epidemiology of podoconiosis. Through systematic searches in SCOPUS and MEDLINE from inception to February 14, 2018, we identified observational and population-based studies reporting podoconiosis. To establish existence of podoconiosis, we used case reports and presence data. For a study to be included in the prevalence synthesis, it needed to be a population-based survey that involved all residents within a specific area. Studies that did not report original data were excluded. We undertook descriptive analyses of the extracted data. This study is registered with PROSPERO, number CRD42018084959. We identified 3,260 records, of which 27 studies met the inclusion criteria. Podoconiosis was described to exist or be endemic in 32 countries, 18 from the African Region, 3 from Asia and 11 from Latin America. Overall, podoconiosis prevalence ranged from 0·10% to 8.08%, was highest in the African region, and was substantially higher in adults than in children and adolescents. The highest reported prevalence values were in Africa (8.08% in Cameroon, 7.45% in Ethiopia, 4.52% in Uganda, 3.87% in Kenya and 2.51% in Tanzania). In India, a single prevalence of 0.21% was recorded from Manipur, Mizoram and Rajasthan states. None of the Latin American countries reported prevalence data. Our data suggest that podoconiosis is more widespread in the African Region than in the rest of the regions, although this could be related to the fact that most podoconiosis epidemiological research has been focused in the African continent. The assembled dataset confirms that comprehensive

"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...

Identifying socioeconomic, epidemiological and operational scenarios for tuberculosis control in Brazil: an ecological study.

PubMed

Pelissari, Daniele Maria; Rocha, Marli Souza; Bartholomay, Patricia; Sanchez, Mauro Niskier; Duarte, Elisabeth Carmen; Arakaki-Sanchez, Denise; Dantas, Cíntia Oliveira; Jacobs, Marina Gasino; Andrade, Kleydson Bonfim; Codenotti, Stefano Barbosa; Andrade, Elaine Silva Nascimento; Araújo, Wildo Navegantes de; Costa, Fernanda Dockhorn; Ramalho, Walter Massa; Diaz-Quijano, Fredi Alexander

2018-06-06

To identify scenarios based on socioeconomic, epidemiological and operational healthcare factors associated with tuberculosis incidence in Brazil. Ecological study. The study was based on new patients with tuberculosis and epidemiological/operational variables of the disease from the Brazilian National Information System for Notifiable Diseases and the Mortality Information System. We also analysed socioeconomic and demographic variables. The units of analysis were the Brazilian municipalities, which in 2015 numbered 5570 but 5 were excluded due to the absence of socioeconomic information. Tuberculosis incidence rate in 2015. We evaluated as independent variables the socioeconomic (2010), epidemiological and operational healthcare indicators of tuberculosis (2014 or 2015) using negative binomial regression. Municipalities were clustered by the k-means method considering the variables identified in multiple regression models. We identified two clusters according to socioeconomic variables associated with the tuberculosis incidence rate (unemployment rate and household crowding): a higher socioeconomic scenario (n=3482 municipalities) with a mean tuberculosis incidence rate of 16.3/100 000 population and a lower socioeconomic scenario (2083 municipalities) with a mean tuberculosis incidence rate of 22.1/100 000 population. In a second stage of clusterisation, we defined four subgroups in each of the socioeconomic scenarios using epidemiological and operational variables such as tuberculosis mortality rate, AIDS case detection rate and proportion of vulnerable population among patients with tuberculosis. Some of the subscenarios identified were characterised by fragility in their information systems, while others were characterised by the concentration of tuberculosis cases in key populations. Clustering municipalities in scenarios allowed us to classify them according to the socioeconomic, epidemiological and operational variables associated with tuberculosis

Pontiac fever: an operational definition for epidemiological studies

PubMed Central

Tossa, Paul; Deloge-Abarkan, Magali; Zmirou-Navier, Denis; Hartemann, Philippe; Mathieu, Laurence

2006-01-01

Background Pontiac fever is usually described in epidemic settings. Detection of Pontiac fever is a marker of an environmental contamination by Legionella and should thereby call for prevention measures in order to prevent outbreak of Legionnaire's disease. The objective of this study is to propose an operational definition of Pontiac fever that is amenable to epidemiological surveillance and investigation in a non epidemic setting. Methods A population of 560 elderly subjects residing in 25 nursing homes was followed during 4 months in order to assess the daily incidence of symptoms associated, in the literature, with Pontiac fever. The water and aerosol of one to 8 showers by nursing home were characterized combining conventional bacterial culture of Legionella and the Fluorescence In Situ Hybridization (FISH) technique that used oligonucleotides probes specific for Legionellaceae. A definition of Pontiac fever was devised based on clinical symptoms described in epidemic investigations and on their timing after the exposure event. The association between incidence of Pontiac fever and shower contamination levels was evaluated to test the relevance of this definition. Results The proposed definition of Pontiac fever associated the following criteria: occurrence of at least one symptom among headache, myalgia, fever and shivers, possibly associated with other 'minor' symptoms, within three days after a shower contaminated by Legionella, during a maximum of 8 days (minimum 2 days). 23 such cases occurred during the study (incidence rate: 0.125 cases per person-year [95% CI: 0.122–0.127]). A concentration of Legionella in water equal to or greater than 104.L-1 (FISH method) was associated with a significant increase of incidence of Pontiac fever (p = 0.04). Conclusion Once validated in other settings, the proposed definition of Pontiac fever might be used to develop epidemiological surveillance and help draw attention on sources of Legionella. PMID:16646972

The Intersection of HPV Epidemiology, Genomics and Mechanistic Studies of HPV-Mediated Carcinogenesis

PubMed Central

Mirabello, Lisa; Clarke, Megan A.; Nelson, Chase W.; Dean, Michael; Wentzensen, Nicolas; Yeager, Meredith; Cullen, Michael; Boland, Joseph F.; Schiffman, Mark

2018-01-01

Of the ~60 human papillomavirus (HPV) genotypes that infect the cervicovaginal epithelium, only 12–13 “high-risk” types are well-established as causing cervical cancer, with HPV16 accounting for over half of all cases worldwide. While HPV16 is the most important carcinogenic type, variants of HPV16 can differ in their carcinogenicity by 10-fold or more in epidemiologic studies. Strong genotype-phenotype associations embedded in the small 8-kb HPV16 genome motivate molecular studies to understand the underlying molecular mechanisms. Understanding the mechanisms of HPV genomic findings is complicated by the linkage of HPV genome variants. A panel of experts in various disciplines gathered on 21 November 2016 to discuss the interdisciplinary science of HPV oncogenesis. Here, we summarize the discussion of the complexity of the viral–host interaction and highlight important next steps for selected applied basic laboratory studies guided by epidemiological genomic findings. PMID:29438321

An Epidemiological Study of Number Processing and Mental Calculation in Greek Schoolchildren

ERIC Educational Resources Information Center

Koumoula, Anastasia; Tsironi, Vanda; Stamouli, Victoria; Bardani, Irini; Stavroula, Siapati; Graham, Annik; Kafantaris, Ignatios; Charalambidou, Irini; Dellatolas, Georges; von Aster, Michael

2004-01-01

The aim of this study was to validate and standardize an instrument for the diagnosis of developmental dyscalculia (mathematics disorder) in a Greek population and to obtain relevant epidemiological data. We used the "Neuropsychological Test Battery for Number Processing and Calculation in Children" (NUCALC) in a community sample of 240 students…

Methods and Processes of Developing the Strengthening the Reporting of Observational Studies in Epidemiology - Veterinary (STROBE-Vet) Statement.

PubMed

Sargeant, J M; O'Connor, A M; Dohoo, I R; Erb, H N; Cevallos, M; Egger, M; Ersbøll, A K; Martin, S W; Nielsen, L R; Pearl, D L; Pfeiffer, D U; Sanchez, J; Torrence, M E; Vigre, H; Waldner, C; Ward, M P

2016-12-01

The reporting of observational studies in veterinary research presents many challenges that often are not adequately addressed in published reporting guidelines. A consensus meeting of experts was organized to develop an extension of the STROBE statement to address observational studies in veterinary medicine with respect to animal health, animal production, animal welfare and food safety outcomes. The consensus meeting was held 11-13 May 2014 in Mississauga, Ontario, Canada. Seventeen experts from North America, Europe and Australia attended the meeting. The experts were epidemiologists and biostatisticians, many of whom hold or have held editorial positions with relevant journals. Prior to the meeting, 19 experts completed a survey about whether they felt any of the 22 items of the STROBE statement should be modified and whether items should be added to address unique issues related to observational studies in animal species with health, production, welfare or food safety outcomes. At the meeting, the participants were provided with the survey responses and relevant literature concerning the reporting of veterinary observational studies. During the meeting, each STROBE item was discussed to determine whether or not re-wording was recommended, and whether additions were warranted. Anonymous voting was used to determine whether there was consensus for each item change or addition. The consensus was that six items needed no modifications or additions. Modifications or additions were made to the STROBE items numbered as follows: 1 (title and abstract), 3 (objectives), 5 (setting), 6 (participants), 7 (variables), 8 (data sources/measurement), 9 (bias), 10 (study size), 12 (statistical methods), 13 (participants), 14 (descriptive data), 15 (outcome data), 16 (main results), 17 (other analyses), 19 (limitations) and 22 (funding). Published literature was not always available to support modification to, or inclusion of, an item. The methods and processes used in the

Renal cell cancer among African Americans: an epidemiologic review

PubMed Central

2011-01-01

Incidence rates for renal cell cancer, which accounts for 85% of kidney cancers, have been rising more rapidly among blacks than whites, almost entirely accounted for by an excess of localized disease. This excess dates back to the 1970s, despite less access among blacks to imaging procedures in the past. In contrast, mortality rates for this cancer have been virtually identical among blacks and whites since the early 1990s, despite the fact that nephrectomy rates, regardless of stage, are lower among blacks than among whites. These observations suggest that renal cell cancer may be a less aggressive tumor in blacks. We have reviewed the epidemiology of renal cell cancer, with emphasis on factors which may potentially play a role in the observed differences in incidence and mortality patterns of renal cell cancer among blacks and whites. To date, the factors most consistently, albeit modestly, associated with increased renal cell cancer risk in epidemiologic studies among whites - obesity, hypertension, cigarette smoking - likely account for less than half of these cancers, and there is virtually no epidemiologic evidence in the literature pertaining to their association with renal cell cancer among blacks. There is a long overdue need for detailed etiologic cohort and case-control studies of renal cell cancer among blacks, as they now represent the population at highest risk in the United States. In particular, investigation of the influence on renal cell cancer development of hypertension and chronic kidney disease, both of which occur substantially more frequently among blacks, is warranted, as well as investigations into the biology and natural history of this cancer among blacks. PMID:21486465

THE 1998 BALTIMORE PARTICULATE MATTER EPIDEMIOLOGY-EXPOSURE STUDY: PART 2-PERSONAL EXPOSURE ASSESSMENT ASSOCIATED WITH AN ELDERLY STUDY POPULATION

EPA Science Inventory

An integrated epidemiological-exposure panel study was conducted during the summer of 1998 which focused upon establishing relationships between potential human exposures to particulate matter (PM) and related co-pollutants with detectable health effects. The study design incor...

DNA methylation analysis from saliva samples for epidemiological studies.

PubMed

Nishitani, Shota; Parets, Sasha E; Haas, Brian W; Smith, Alicia K

2018-06-18

Saliva is a non-invasive, easily accessible tissue, which is regularly collected in large epidemiological studies to examine genetic questions. Recently, it is becoming more common to use saliva to assess DNA methylation. However, DNA extracted from saliva is a mixture of both bacterial and human DNA derived from epithelial and immune cells in the mouth. Thus, there are unique challenges to using salivary DNA in methylation studies that can influence data quality. This study assesses: (1) quantification of human DNA after extraction; (2) delineation of human and bacterial DNA; (3) bisulfite conversion (BSC); (4) quantification of BSC DNA; (5) PCR amplification of BSC DNA from saliva and; (6) quantitation of DNA methylation with a targeted assay. The framework proposed will allow saliva samples to be more widely used in targeted epigenetic studies.

Portable Functional Neuroimaging as an Environmental Epidemiology Tool: A How-To Guide for the Use of fNIRS in Field Studies.

PubMed

Baker, Joseph M; Rojas-Valverde, Daniel; Gutiérrez, Randall; Winkler, Mirko; Fuhrimann, Samuel; Eskenazi, Brenda; Reiss, Allan L; Mora, Ana M

2017-09-21

The widespread application of functional neuroimaging within the field of environmental epidemiology has the potential to greatly enhance our understanding of how environmental toxicants affect brain function. Because many epidemiological studies take place in remote and frequently changing environments, it is necessary that the primary neuroimaging approach adopted by the epidemiology community be robust to many environments, easy to use, and, preferably, mobile. Here, we outline our use of functional near-infrared spectroscopy (fNIRS) to collect functional brain imaging data from Costa Rican farm workers enrolled in an epidemiological study on the health effects of chronic pesticide exposure. While couched in this perspective, we focus on the methodological considerations that are necessary to conduct a mobile fNIRS study in a diverse range of environments. Thus, this guide is intended to be generalizable to all research scenarios and projects in which fNIRS may be used to collect functional brain imaging data in epidemiological field surveys. https://doi.org/10.1289/EHP2049.

Portable Functional Neuroimaging as an Environmental Epidemiology Tool: A How-To Guide for the Use of fNIRS in Field Studies

PubMed Central

Rojas-Valverde, Daniel; Gutiérrez, Randall; Winkler, Mirko; Fuhrimann, Samuel; Eskenazi, Brenda; Reiss, Allan L.; Mora, Ana M.

2017-01-01

Summary: The widespread application of functional neuroimaging within the field of environmental epidemiology has the potential to greatly enhance our understanding of how environmental toxicants affect brain function. Because many epidemiological studies take place in remote and frequently changing environments, it is necessary that the primary neuroimaging approach adopted by the epidemiology community be robust to many environments, easy to use, and, preferably, mobile. Here, we outline our use of functional near-infrared spectroscopy (fNIRS) to collect functional brain imaging data from Costa Rican farm workers enrolled in an epidemiological study on the health effects of chronic pesticide exposure. While couched in this perspective, we focus on the methodological considerations that are necessary to conduct a mobile fNIRS study in a diverse range of environments. Thus, this guide is intended to be generalizable to all research scenarios and projects in which fNIRS may be used to collect functional brain imaging data in epidemiological field surveys. https://doi.org/10.1289/EHP2049 PMID:28937962

Genetics of schizophrenia and smoking: an approach to studying their comorbidity based on epidemiological findings

PubMed Central

de Leon, Jose; Diaz, Francisco J.

2012-01-01

The association between schizophrenia and tobacco smoking has been described in more than 1,000 articles, many with inadequate methodology. The studies on this association can focus on: (1) current smoking, ever smoking or smoking cessation; (2) non-psychiatric controls or controls with severe mental illness (e.g., bipolar disorder); and (3) higher smoking frequency or greater usage in smokers. The association with the most potential for genetic studies is that between ever daily smoking and schizophrenia; it may reflect a shared genetic vulnerability. To reduce the number of false-positive genes, we propose a three-stage approach derived from epidemiological knowledge. In the first stage, only genetic variations associated with ever daily smoking that are simultaneously significant within the non-psychiatric controls, the bipolar disorder controls and the schizophrenia cases will be selected. Only those genetic variations that are simultaneously significant in the three hypothesis tests will be tested in the second stage, where the prevalence of the genes must be significantly higher in schizophrenia than in bipolar disorder, and significantly higher in bipolar disorder than in controls. The genes simultaneously significant in the second stage will be included in a third stage where the gene variations must be significantly more frequent in schizophrenia patients who did not start smoking daily until their 20s (late start) versus those who had an early start. Any genetic approach to psychiatric disorders may fail if attention is not given to comorbidity and epidemiological studies that suggest which comorbidities are likely to be explained by genetics and which are not. Our approach, which examines the results of epidemiological studies on comorbidities and then looks for genes that simultaneously satisfy epidemiologically suggested sets of hypotheses, may also apply to the study of other major illnesses. PMID:22190153

An animated depiction of major depression epidemiology.

PubMed

Patten, Scott B

2007-06-08

Epidemiologic estimates are now available for a variety of parameters related to major depression epidemiology (incidence, prevalence, etc.). These estimates are potentially useful for policy and planning purposes, but it is first necessary that they be synthesized into a coherent picture of the epidemiology of the condition. Several attempts to do so have been made using mathematical modeling procedures. However, this information is not easy to communicate to users of epidemiological data (clinicians, administrators, policy makers). In this study, up-to-date data on major depression epidemiology were integrated using a discrete event simulation model. The mathematical model was animated in Virtual Reality Modeling Language (VRML) to create a visual, rather than mathematical, depiction of the epidemiology. Consistent with existing literature, the model highlights potential advantages of population health strategies that emphasize access to effective long-term treatment. The paper contains a web-link to the animation. Visual animation of epidemiological results may be an effective knowledge translation tool. In clinical practice, such animations could potentially assist with patient education and enhanced long-term compliance.

Exposure prediction approaches used in air pollution epidemiology studies: Keyfindings and future recommendations

EPA Science Inventory

Many epidemiologic studies of the health effects of exposure to ambient air pollution use measurements from central-site monitors as their exposure estimate. However, measurements from central-site monitors may lack the spatial and temporal resolution required to capture exposure...

Exposure to phthalates: reproductive outcome and children health. A review of epidemiological studies.

PubMed

Jurewicz, Joanna; Hanke, Wojciech

2011-06-01

Phthalates are a family of industrial chemicals that have been used for a variety of purposes. As the potential consequences of human exposure to phthalates have raised concerns in the general population, they have been studied in susceptible subjects such as pregnant women, infants and children. This article aims at evaluating the impact of exposure to phthalates on reproductive outcomes and children health by reviewing most recent published literature. Epidemiological studies focusing on exposure to phthalates and pregnancy outcome, genital development, semen quality, precocious puberty, thyroid function, respiratory symptoms and neurodevelopment in children for the last ten years were identified by a search of the PubMed, Medline, Ebsco, Agricola and Toxnet literature bases. The results from the presented studies suggest that there are strong and rather consistent indications that phthalates increase the risk of allergy and asthma and have an adverse impact on children's neurodevelopment reflected by quality of alertness among girls, decreased (less masculine) composite score in boys and attention deficit hyperactivity disorder. Results of few studies demonstrate negative associations between phthalate levels commonly experienced by the public and impaired sperm quality (concentration, morphology, motility). Phthalates negatively impact also on gestational age and head circumference; however, the results of the studies were not consistent. In all the reviewed studies, exposure to phthalates adversely affected the level of reproductive hormones (luteinizing hormone, free testosterone, sex hormone-binding globulin), anogenital distance and thyroid function. The urinary levels of phthalates were significantly higher in the pubertal gynecomastia group, in serum in girls with premature thelarche and in girls with precocious puberty. Epidemiological studies, in spite of their limitations, suggest that phthalates may affect reproductive outcome and children health

[Taenia saginata, a historical, ecological and epidemiological study].

PubMed

Engelbrecht, H

1984-03-01

Taenia saginata, considerations on the history of discovery, on ecology and epidemiology. The influence of urbanisation on the distribution of Taenia saginata has been investigated. It seems suitable both from ecological and epidemiological aspects to divide the life cycle of T. saginata in a primary, direct cycle ( biotop type I), and a secondary, indirect cycle (biotope type II). The two adjectives (direct and indirect) denote the routes of transportation of taeniid eggs to cattle as well as of metacestodes to man. In the secondary cycle the contact between man and cattle or vice-versa is stopped owing to artificial biotop elements. There is a development of cycles closing themselves in a large territory and of transregional open infection chains. The totality of these infection chains shapes the life cycle. The secondary cycle is defined as "urban host-changing cycle" of T. saginata. The degree of sewage clarification is responsible for the incidence of infection with bovine cysticercosis. The conclusions are illustrated by 3 diagrams.

Reverse epidemiology beyond dialysis patients: chronic heart failure, geriatrics, rheumatoid arthritis, COPD, and AIDS.

PubMed

Horwich, Tamara B; Fonarow, Gregg C

2007-01-01

"Reverse epidemiology" refers to paradoxical and counterintuitive epidemiologic associations between survival outcomes and traditional cardiovascular risk factors such as obesity, high blood pressure, and high cholesterol. Reverse epidemiology has been well described in end stage renal disease, but also has been observed in chronic disease states, including chronic heart failure, rheumatoid arthritis, chronic obstructive pulmonary disease, and Acquired Immune Deficiency Syndrome, and in elderly populations. This review will highlight the recent medical literature on reverse epidemiology in these populations. Common pathophysiologic underpinnings in these chronic disease states may help explain the reversal of risk factors observed in these diverse populations. Furthermore, guidelines for the general population for optimal goals of weight, cholesterol levels, and blood pressure may not apply to special populations, including patients with chronic diseases or elderly persons.

The epidemiology and resuscitation effects of cardiopulmonary arrest among hospitalized children and adolescents in Beijing: an observational study.

PubMed

Zeng, Jiansheng; Qian, Suyun; Zheng, Mingqiong; Wang, Yin; Zhou, Gaojun; Wang, Haiyan

2013-12-01

To investigate the epidemiology and resuscitation effects of cardiopulmonary arrest among hospitalized children and adolescents in Beijing. A prospective multicentre study was conducted in four hospitals in urban/suburban areas of Beijing. Patients aged 1 month-18 years with cardiopulmonary arrest and received cardiopulmonary resuscitation (CPR) who were consecutively hospitalised during the study period (1 September 2008-31 December 2010) were enrolled. Data was collected and analyzed using the "in-hospital Utstein style". Neurological outcome was assessed with the pediatric cerebral performance category (PCPC) among patients who survived. 201 of 108,673 hospitalized patients (0.18%) had cardiopulmonary arrest during their hospitalization. Of these, 174 patients underwent CPR. The most common causes of cardiopulmonary arrest were the diseases of respiratory system (29.3%) and circulatory system (19.0%). The most common initial rhythm was bradycardia (72.4%). About 108 patients (62.1%) had restoration of spontaneous circulation (ROSC). Forty-nine patients (28.2%) survived to hospital discharge, 25 (14.5%) survived 6 months post discharge, and 21 (12.1%) survived 1 year post discharge. Out of the 21 patients who survived 1 year after hospital discharge, 18 had good neurological outcome. Multivariate logistic regression analysis showed age, duration of CPR and endotracheal intubation performed before cardiopulmonary arrest were independent factors of cardiopulmonary resuscitation effect. The prevalence of in-hospital cardiopulmonary arrest in children and adolescents is low. The long-term result of children and adolescents survived from cardiopulmonary resuscitation is quite good. Age, CPR duration and endotracheal intubation performed before cardiopulmonary arrest were independent factors of cardiopulmonary resuscitation effect. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Strengthening the Reporting of Molecular Epidemiology for Infectious Diseases (STROME-ID): an extension of the STROBE statement.

PubMed

Field, Nigel; Cohen, Ted; Struelens, Marc J; Palm, Daniel; Cookson, Barry; Glynn, Judith R; Gallo, Valentina; Ramsay, Mary; Sonnenberg, Pam; Maccannell, Duncan; Charlett, Andre; Egger, Matthias; Green, Jonathan; Vineis, Paolo; Abubakar, Ibrahim

2014-04-01

Molecular data are now widely used in epidemiological studies to investigate the transmission, distribution, biology, and diversity of pathogens. Our objective was to establish recommendations to support good scientific reporting of molecular epidemiological studies to encourage authors to consider specific threats to valid inference. The statement Strengthening the Reporting of Molecular Epidemiology for Infectious Diseases (STROME-ID) builds upon the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) initiative. The STROME-ID statement was developed by a working group of epidemiologists, statisticians, bioinformaticians, virologists, and microbiologists with expertise in control of infection and communicable diseases. The statement focuses on issues relating to the reporting of epidemiological studies of infectious diseases using molecular data that were not addressed by STROBE. STROME-ID addresses terminology, measures of genetic diversity within pathogen populations, laboratory methods, sample collection, use of molecular markers, molecular clocks, timeframe, multiple-strain infections, non-independence of infectious-disease data, missing data, ascertainment bias, consistency between molecular and epidemiological data, and ethical considerations with respect to infectious-disease research. In total, 20 items were added to the 22 item STROBE checklist. When used, the STROME-ID recommendations should advance the quality and transparency of scientific reporting, with clear benefits for evidence reviews and health-policy decision making. Copyright © 2014 Elsevier Ltd. All rights reserved.

Epidemiology: Informing Clinical Practice and Research on Language Disorders in Children.

ERIC Educational Resources Information Center

Lubker, Bobbie Boyd; Tomblin, J. Bruce

1998-01-01

Describes the discipline of epidemiology and the application of epidemiologic methods to the study of children's language disorders. Epidemiology is described as the study of the distributions and determinants of disease, disorders, disabilities, and desirable health events in populations. Common epidemiologic research designs are discussed.…

[Occupational epidemiology: some methodological considerations].

PubMed

Alvear-Galindo, María Guadalupe; del Pilar Paz-Román, María

2006-01-01

During the last decade, occupational epidemiology has gained a great importance, not only because of the increase of pollutants and their noxiousness, but also because it has gone from the descriptive to the analytic level. The purpose of this work is to present what has been reported on epidemiological studies, different ways of characterizing and measuring occupational exposure, by emphasizing slants of exposure and selection measurement. In the reviewed studies, an interest in improving the exposure evaluation has been shown. The mainly reported measurement slants are the ways of measuring and classifying the exposure. The main designs were transversal with the use of matrixes to improve the evaluation of exposure. Conditions of hygiene and security were considered in order to control the quality of the information. This information was analyzed with different criteria. Some of the elements that hinder the research on occupational epidemiology are a mixed exposure, small populations, lack of exposure data, low levels of exposure and long periods of illness latency. Some breakthroughs in the strategies of epidemiological analysis and some other areas of knowledge have made possible a better understanding of work and health conditions of workers.

Observations on the epidemiology and control of Strongylus vulgaris infections.

PubMed

Eysker, M; Wemmenhove, R

1987-01-01

The epidemiology and control of helminth infections in the horse were studied in four small grazing experiments between 1981 and 1984 at the University of Utrecht. At autopsy in November or December negligible Strongylus vulgaris burdens were found in the cranial mesenteric artery of four groups of ponies, which had been treated with an anthelmintic in July and subsequently transferred to a clean pasture. Considerable arterial S. vulgaris burdens were seen in three groups of ponies which were treated with an anthelmintic in July without a move to clean pasture, and in another group of ponies in 1984, which was set stocked on a pasture used for horses in 1983 and which was treated with an anthelmintic (albendazole) 2 days before turnout in April and subsequently in May, June and July. A tracer pony, grazed with this group between the middle of September and the middle of November, harboured an even higher burden of arterial S. vulgaris larvae. The arterial S. vulgaris in the latter group could not be the result of contamination of the pasture with S. vulgaris eggs before July, as in the three other groups with considerable arterial S. vulgaris burdens. Pasture larval counts showed that S. vulgaris larvae do not only overwinter, but are able to survive in considerable numbers until autumn, longer than most other gastrointestinal nematodes. There were some indications that translation of infective larvae, which overwintered on pasture in some free living stage, occurred between May and July.

Genetics and epidemiology, congenital anomalies and cancer

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

Friedman, J.M.

1997-03-01

Many of the basic statistical methods used in epidemiology - regression, analysis of variance, and estimation of relative risk, for example - originally were developed for the genetic analysis of biometric data. The familiarity that many geneticists have with this methodology has helped geneticists to understand and accept genetic epidemiology as a scientific discipline. It worth noting, however, that most of the work in genetic epidemiology during the past decade has been devoted to linkage and other family studies, rather than to population-based investigations of the type that characterize much of mainstream epidemiology. 30 refs., 2 tabs.

A clinico-epidemiological study of herpes zoster.

PubMed

Aggarwal, S K; Radhakrishnan, S

2016-04-01

Herpes zoster is a common viral infection of skin caused by reactivation of varicella zoster virus infection from the spinal ganglia. The clinico-epidemiological patterns of this disease in an Indian setting required to be studied. A cross sectional study was conducted on all consecutive cases of herpes zoster reporting to the Dermatology Outpatient Department at a Tertiary Care Hospital in Bangalore during a period of one year from 01 Jun 2013 to 31 May 2014. Detailed history, examination, HIV screening and Tzanck smear were carried out in all cases. 84 cases of herpes zoster were seen with a mean age of 30 years. Majority (39%) of cases were seen in the 21-30 year age group. Thoracic segments were involved in 65.4%, cervical in 11.9%, cranial in 11.5%, lumbar in 8.3% and sacral segments in 3.5%. 63% of cases had zoster associated pain. One case had motor involvement.3.57% of the patients were HIV positive. This study shows a lower age incidence of herpes zoster HIV positivity and zoster associated pain as compared to other studies. The pattern of segmental involvement in herpes zoster seen in this study was similar to other studies.

Validating the Center for Epidemiological Studies Depression Scale for Children in Rwanda

ERIC Educational Resources Information Center

Betancourt, Theresa; Scorza, Pamela; Meyers-Ohki, Sarah; Mushashi, Christina; Kayiteshonga, Yvonne; Binagwaho, Agnes; Stulac, Sara; Beardslee, William R.

2012-01-01

Objective: We assessed the validity of the Center for Epidemiological Studies Depression Scale for Children (CES-DC) as a screen for depression in Rwandan children and adolescents. Although the CES-DC is widely used for depression screening in high-income countries, its validity in low-income and culturally diverse settings, including sub-Saharan…

Sleep duration and cardiometabolic risk: a review of the epidemiologic evidence.

PubMed

Knutson, Kristen L

2010-10-01

Laboratory studies have found that short-term sleep restriction is associated with impairments in glucose metabolism, appetite regulation and blood pressure regulation. This chapter reviews the epidemiologic evidence for an association between habitual sleep duration and quality and risk of cardiometabolic diseases including obesity, diabetes and hypertension. Multiple studies observed a cross-sectional association between short sleep duration (generally <6 h per night) and increased body mass index or obesity, prevalent diabetes and prevalent hypertension. Many studies also reported an association between self-reported long sleep duration (generally >8 h per night) and cardiometabolic disease. There have been a few prospective studies and several, but not all, have found an association between short sleep and incident diabetes, hypertension and markers of cardiovascular disease. Future prospective epidemiologic studies need to include objective measures of sleep, and intervention studies are needed in order to establish a causal link between impaired or insufficient sleep and cardiometabolic disease risk. Copyright © 2010 Elsevier Ltd. All rights reserved.

Study of Resource Recovery and Epidemiology in an Anaerobic Digester

NASA Technical Reports Server (NTRS)

Li, K. Y.; Cao, Song; Hunt, M. D.; Fu, Xuping

1995-01-01

Three 4-liter packed bed anaerobic digesters were fabricated and operated at 35 degrees C, pH around 7, and hydraulic retention time (HRT) of 20, 10 and 5 days to study the resource recovery and epidemiology in a controlled ecological life support system (CELSS). A simulated wastewater, consisted of shower water, clothwash water, dishwasher water, handwash water, and urine flush water was used as the feeding solution. Under steady-state operation, chemical oxygen demand (COD), total organic carbon (TOC), pH, nitrogen, phosphorus, and potassium wer monitored in the digester input and output solutions. The volume and the CH4/CO2 ratios in the biogas produced from the anaerobic digesters were measured. The results indicate about 90 percent of TOC is converted while only 5-8 percent of N-P-K are consumed in the digester. A multi-drug resistant strain of Salmonella choleraesuis was used as the indicator bacterium in the epidemiology study. The levels of Salmonella choleraesuis in the influent and the effluent wer determined and decimal decay rate constants, k(d), were estimated. The k(d) values were greater at higher initial doses than lower doses for the same HR, and greater for batch digestion (7.89/d) than for continuous digestion (4.28, 3.82, and 3.82/d for 20, 10, and 5 d HRT, respectively).

Geometrically Evident: Framing Studies Using the Graphic Appraisal Tool for Epidemiology (GATE)

ERIC Educational Resources Information Center

Martin, Andres; Srihari, Vinod

2006-01-01

Educators in evidence-based medicine (EBM) have noted that the core set of epidemiological concepts outlined in standard sources are sometimes put to use as oversimplified checklists for the appraisal of research reports. In this article, the authors present the Graphic Appraisal Tool for Epidemiology which was designed as a way combat, by visual…

[Biological markers in epidemiology: concepts, applications, perspectives (part I)].

PubMed

Hoffmann, W; Latza, U; Ahrens, W; Greiser, K H; Kroke, A; Nieters, A; Schulze, M B; Steiner, M; Terschüren, C; Wjst, M

2002-02-01

The inclusion of biomarkers in epidemiological research provides new possibilities for exposure assessment and the study of early structural or functional changes and pre-clinical stages of diseases. At the same time issues of validity, reliability, and quality control as well as logistics require special attention. Usually epidemiological studies become more expensive with regard to time and cost. Interdisciplinary collaboration between epidemiology, basic research, and laboratory research is crucial. A prerequisite for this collaboration are agreements on definitions, methods and procedures. The definition of "biomarker" and a description of previous uses of biomarkers in epidemiological studies are presented in the first part of this paper. The second part addresses genetic markers and markers of individual sensitivity and susceptibility. We will end with a discussion about the possible future of biomarkers in epidemiology.

Epidemiology of atlas fractures--a national registry-based cohort study of 1,537 cases.

PubMed

Matthiessen, Christian; Robinson, Yohan

2015-11-01

The epidemiology of fractures of the first cervical vertebra-the atlas-has not been well documented. Previous studies concerning atlas fractures focus on treatment and form a weak platform for epidemiologic study. This study aims to provide reliable epidemiologic data on atlas fractures. This was a national registry-based cohort study. A total of 1,537 cases of atlas fractures between 1997 and 2011 from the Swedish National Patient Registry (NPR). The outcome measures were annual incidence and mortality. Data from the NPR and the Swedish Cause of Death Registry were extracted, including age, gender, diagnosis, comorbidity, treatment codes, and date of death. The Charlson Comorbidity Index was calculated and a survival analysis performed. A total of 869 (56.5%) cases were men, and 668 (43.5%) were women. The mean age of the entire population was 64 years. The proportion of atlas fractures of all registered cervical fractures was 10.6%. In 19% of all cases, there was an additional fracture of the axis, and 7% of all cases had additional subaxial cervical fractures. Patients with fractures of the axis were older than patients with isolated atlas fractures. The annual incidence almost doubled during the study period, and in 2011, it was 17 per million inhabitants. The greatest increase in incidence occurred in the elderly population. Atlas fractures occurred predominantly in the elderly population. Further study is needed to determine the cause of the increasing incidence. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Problems and Benefits Reported by Stroke Family Caregivers: Results from a Prospective Epidemiological Study

PubMed Central

Haley, William E.; Allen, Jessica Y.; Grant, Joan S.; Clay, Olivio J.; Perkins, Martinique; Roth, David L.

2009-01-01

Background and Purpose Stroke symptoms can be very stressful for family caregivers, but most knowledge about the prevalence and stressfulness of stroke-related patient problems is derived from convenience samples. In addition, little is known about perceived benefits of the stroke caregiving experience. The purpose of this study was to determine the prevalence and stressfulness of stroke-related problems, and perceived benefits of caregiving, as reported by an epidemiologically-derived sample of caregivers of stroke survivors. Methods Stroke survivors (N=75) from a prospective epidemiological study of stroke, the REasons for Geographic and Racial Differences in Stroke (REGARDS) study, and their family caregivers were followed. Caregivers were given a comprehensive telephone interview 8 to 12 months after the stroke, using measures of stroke patient problems, caregiver appraisals of the stressfulness of these problems, and perceived benefits of caregiving. Results Caregivers rated patient problems with mood (depression, loneliness and anxiety), memory, and physical care (bowel control), as the most stressful, but reported prevalence of these problems was lower than those reported previously in studies using clinical samples. Caregivers also reported many benefits from caregiving, with over 90% reporting that caregiving enabled them to appreciate life more. Conclusions Epidemiologically based studies of stroke caregiving provide a unique picture of caregiver strains and benefits compared with clinical studies, which tend to over-represent more impaired patients. Support for caregivers should include interventions to aid their coping with highly stressful mood, physical care, and cognitive problems of stroke patients, but should also attend to perceived benefits of caregiving. PMID:19407230

Putting Life into Computer-Based Training: The Creation of an Epidemiologic Case Study.

ERIC Educational Resources Information Center

Gathany, Nancy C.; Stehr-Green, Jeanette K.

1994-01-01

Describes the design of "Pharyngitis in Louisiana," a computer-based epidemiologic case study that was created to teach students how to conduct disease outbreak investigations. Topics discussed include realistic content portrayals; graphics; interactive teaching methods; interaction between the instructional designer and the medical…

Choline and betaine consumption lowers cancer risk: a meta-analysis of epidemiologic studies.

PubMed

Sun, Shanwen; Li, Xiao; Ren, Anjing; Du, Mulong; Du, Haina; Shu, Yongqian; Zhu, Lingjun; Wang, Wei

2016-10-19

A number of human and animal in vitro or in vivo studies have investigated the relationship between dietary choline and betaine and cancer risk, suggesting that choline and betaine consumption may be protective for cancer. There are also a few epidemiologic studies exploring this relationship, however, with inconsistent conclusions. The PubMed and Embase were searched, from their inception to March 2016, to identify relevant studies and we brought 11 articles into this meta-analysis eventually. The pooled relative risks (RRs) of cancer for the highest versus the lowest range were 0.82 (95% CI, 0.70 to 0.97) for choline consumption only, 0.86 (95%CI, 0.76 to 0.97) for betaine consumption only and 0.60 (95%CI, 0.40 to 0.90) for choline plus betaine consumption, respectively. Significant protective effect of dietary choline and betaine for cancer was observed when stratified by study design, location, cancer type, publication year, sex and quality score of study. An increment of 100 mg/day of choline plus betaine intake helped reduce cancer incidence by 11% (0.89, 95% CI, 0.87 to 0.92) through a dose-response analysis. To conclude, choline and betaine consumption lowers cancer incidence in this meta-analysis, but further studies are warranted to verify the results.

Epidemiological Trends of Dengue Disease in Brazil (2000–2010): A Systematic Literature Search and Analysis

PubMed Central

Teixeira, Maria Glória; Siqueira,, João Bosco; Ferreira, Germano L. C.; Bricks, Lucia; Joint, Graham

2013-01-01

A literature survey and analysis was conducted to describe the epidemiology of dengue disease in Brazil reported between 2000 and 2010. The protocol was registered on PROSPERO (CRD42011001826: http://www.crd.york.ac.uk/prospero/display_record.asp?ID=CRD42011001826). Between 31 July and 4 August 2011, the published literature was searched for epidemiological studies of dengue disease, using specific search strategies for each electronic database. A total of 714 relevant citations were identified, 51 of which fulfilled the inclusion criteria. The epidemiology of dengue disease in Brazil, in this period, was characterized by increases in the geographical spread and incidence of reported cases. The overall increase in dengue disease was accompanied by a rise in the proportion of severe cases. The epidemiological pattern of dengue disease in Brazil is complex and the changes observed during this review period are likely to have been influenced by multiple factors. Several gaps in epidemiological knowledge regarding dengue disease in Brazil were identified that provide avenues for future research, in particular, studies of regional differences, genotype evolution, and age-stratified seroprevalence. Systematic Review Registration PROSPERO registration number: CRD42011001826. PMID:24386496

Current approaches used in epidemiologic studies to examine short-term multipollutant air pollution exposures.

PubMed

Davalos, Angel D; Luben, Thomas J; Herring, Amy H; Sacks, Jason D

2017-02-01

Air pollution epidemiology traditionally focuses on the relationship between individual air pollutants and health outcomes (e.g., mortality). To account for potential copollutant confounding, individual pollutant associations are often estimated by adjusting or controlling for other pollutants in the mixture. Recently, the need to characterize the relationship between health outcomes and the larger multipollutant mixture has been emphasized in an attempt to better protect public health and inform more sustainable air quality management decisions. New and innovative statistical methods to examine multipollutant exposures were identified through a broad literature search, with a specific focus on those statistical approaches currently used in epidemiologic studies of short-term exposures to criteria air pollutants (i.e., particulate matter, carbon monoxide, sulfur dioxide, nitrogen dioxide, and ozone). Five broad classes of statistical approaches were identified for examining associations between short-term multipollutant exposures and health outcomes, specifically additive main effects, effect measure modification, unsupervised dimension reduction, supervised dimension reduction, and nonparametric methods. These approaches are characterized including advantages and limitations in different epidemiologic scenarios. By highlighting the characteristics of various studies in which multipollutant statistical methods have been used, this review provides epidemiologists and biostatisticians with a resource to aid in the selection of the most optimal statistical method to use when examining multipollutant exposures. Published by Elsevier Inc.

World Epidemiology Review, Number 90

DTIC Science & Technology

1978-01-12

Bom Jesus and Aurora do Norte. This was reported to Agriculture Minister Alysson Paulinelli in Brasilia by Antonio Augusto Azeredo Coutinho, the...municipios of Dianopolis, Ponte Alta de Bom Jesus , Almas and Alvorada to observe the situation. He confirmed that the rabies outbreak has affected...department has established a system of epidemiological vigilance, which consists of receiving, every 7 days, information from all municipal hospitals

Epidemiology of Gout

PubMed Central

Choi, Hyon

2014-01-01

Synopsis Gout is the most prevalent inflammatory arthritis in men. The findings of several epidemiological studies from a diverse range of countries suggest that the prevalence of gout has risen over the last few decades. Whilst incidence data are scarce, data from the US suggests that the incidence of gout is also rising. Evidence from prospective epidemiological studies has confirmed dietary factors (animal purines, alcohol and fructose), obesity, the metabolic syndrome, hypertension, diuretic use, and chronic kidney disease as clinically relevant risk factors for hyperuricemia and gout. Low-fat dairy products, coffee, and vitamin C appear to have a protective effect. Further prospective studies are required to examine other proposed risk factors for hyperuricaemia and gout such as the use of β-blockers and angiotension-II receptor antagonists (other than losartan), obstructive sleep apnoea, and osteoarthritis, and putative protective factors such as calcium-channel blockers and losartan. PMID:24703341

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.

The Current Status of the Disease Caused by Enterovirus 71 Infections: Epidemiology, Pathogenesis, Molecular Epidemiology, and Vaccine Development

PubMed Central

Chang, Ping-Chin; Chen, Shou-Chien; Chen, Kow-Tong

2016-01-01

Enterovirus 71 (EV71) infections have a major public health impact in the Asia-Pacific region. We reviewed the epidemiology, pathogenesis, and molecular epidemiology of EV71 infection as well as EV71 vaccine development. Previous studies were found using the search terms “enterovirus 71” and “epidemiology” or “pathogenesis” or “molecular epidemiology” or “vaccine” in Medline and PubMed. Articles that were not published in the English language, manuscripts without an abstract, and opinion articles were excluded from the review. The reported epidemiology of cases caused by EV71 infection varied from country to country; seasonal variations in incidence were observed. Most cases of EV71 infection that resulted in hospitalization for complications occurred in children less than five years old. The brainstem was the most likely major target of EV71 infection. The emergence of the EV71 epidemic in the Asia-Pacific region has been associated with the circulation of different genetic lineages (genotypes B3, B4, C1, C2, and C4) that appear to be undergoing rapid evolutionary changes. The relationship between the gene structure of the EV71 virus and the factors that ensure its survival, circulation, and evasion of immunity is still unknown. EV71 infection has emerged as an important global public health problem. Vaccine development, including the development of inactivated whole-virus live attenuated, subviral particles, and DNA vaccines, has been progressing. PMID:27618078

Causality and causal inference in epidemiology: the need for a pluralistic approach

PubMed Central

Vandenbroucke, Jan P; Broadbent, Alex; Pearce, Neil

2016-01-01

Abstract Causal inference based on a restricted version of the potential outcomes approach reasoning is assuming an increasingly prominent place in the teaching and practice of epidemiology. The proposed concepts and methods are useful for particular problems, but it would be of concern if the theory and practice of the complete field of epidemiology were to become restricted to this single approach to causal inference. Our concerns are that this theory restricts the questions that epidemiologists may ask and the study designs that they may consider. It also restricts the evidence that may be considered acceptable to assess causality, and thereby the evidence that may be considered acceptable for scientific and public health decision making. These restrictions are based on a particular conceptual framework for thinking about causality. In Section 1, we describe the characteristics of the restricted potential outcomes approach (RPOA) and show that there is a methodological movement which advocates these principles, not just for solving particular problems, but as ideals for which epidemiology as a whole should strive. In Section 2, we seek to show that the limitation of epidemiology to one particular view of the nature of causality is problematic. In Section 3, we argue that the RPOA is also problematic with regard to the assessment of causality. We argue that it threatens to restrict study design choice, to wrongly discredit the results of types of observational studies that have been very useful in the past and to damage the teaching of epidemiological reasoning. Finally, in Section 4 we set out what we regard as a more reasonable ‘working hypothesis’ as to the nature of causality and its assessment: pragmatic pluralism. PMID:26800751

A Clinico-Epidemiological Study of Macular Amyloidosis from North India

PubMed Central

Bandhlish, Anshu; Aggarwal, Asok; Koranne, Ravinder V

2012-01-01

Background: Macular amyloidosis (MA) is the most subtle form of cutaneous amyloidosis, characterized by brownish macules in a rippled pattern, distributed predominantly over the trunk and extremities. MA has a high incidence in Asia, Middle East, and South America. Its etiology has yet to be fully elucidated though various risk factors such as sex, race, genetic predisposition, exposure to sunlight, atopy and friction and even auto-immunity have been implicated. Aim: This study attempts to evaluate the epidemiology and risk factors in the etiology of MA. Materials and: Methods: Clinical history and risk factors of 50 patients with a clinical diagnosis of MA were evaluated. Skin biopsies of 26 randomly selected patients were studied for the deposition of amyloid. Results: We observed a characteristic female preponderance (88%) with a female to male ratio of 7.3:1, with a mean age of onset of MA being earlier in females. Upper back was involved in 80% of patients and sun-exposed sites were involved in 64% cases. Incidence of MA was high in patients with skin phototype III. Role of friction was inconclusive Conclusion: Lack of clear-cut etiological factors makes it difficult to suggest a reasonable therapeutic modality. Histopathology is not specific and amyloid deposits can be demonstrated only in a small number of patients. For want of the requisite information on the natural course and definitive etiology, the disease MA remains an enigma and a source of concern for the suffering patients. PMID:22837559

Should the history of epidemiology be taught in epidemiology training programs?

PubMed

Laskaris, Zoey; Morabia, Alfredo

2015-01-01

Currently, there is no evidence concerning the presence of historical content in the epidemiology curricula of the United States and abroad. Similarly, it is not known how epidemiologists view this topic in the context of master's or doctoral level course work. We attempted to fill these knowledge gaps with data from 2 online surveys-Survey I administered to persons in charge of all epidemiology training programs in North America and Survey II to epidemiologists practicing around the world. A substantial minority (39%) of graduate programs in epidemiology in the United States teach a course on the history of the field. In both surveys, the most common reasons selected for teaching such a course were "To build a sense of identity as an epidemiologist" and "As a tool for achieving a deeper understanding into specific methods and concepts." The majority of respondents, from 63 countries, agreed that the history of epidemiology should be included in curricula for graduate students in epidemiology.

Atherogenesis and iron: from epidemiology to cellular level

PubMed Central

Vinchi, Francesca; Muckenthaler, Martina U.; Da Silva, Milene C.; Balla, György; Balla, József; Jeney, Viktória

2014-01-01

Iron accumulates in human atherosclerotic lesions but whether it is a cause or simply a downstream consequence of the atheroma formation has been an open question for decades. According to the so called “iron hypothesis,” iron is believed to be detrimental for the cardiovascular system, thus promoting atherosclerosis development and progression. Iron, in its catalytically active form, can participate in the generation of reactive oxygen species and induce lipid-peroxidation, triggering endothelial activation, smooth muscle cell proliferation and macrophage activation; all of these processes are considered to be proatherogenic. On the other hand, the observation that hemochromatotic patients, affected by life-long iron overload, do not show any increased incidence of atherosclerosis is perceived as the most convincing evidence against the “iron hypothesis.” Epidemiological studies and data from animal models provided conflicting evidences about the role of iron in atherogenesis. Therefore, more careful studies are needed in which issues like the source and the compartmentalization of iron will be addressed. This review article summarizes what we have learnt about iron and atherosclerosis from epidemiological studies, animal models and cellular systems and highlights the rather contributory than innocent role of iron in atherogenesis. PMID:24847266

The application of epidemiology in aquatic animal health -opportunities and challenges

PubMed Central

2011-01-01

Over recent years the growth in aquaculture, accompanied by the emergence of new and transboundary diseases, has stimulated epidemiological studies of aquatic animal diseases. Great potential exists for both observational and theoretical approaches to investigate the processes driving emergence but, to date, compared to terrestrial systems, relatively few studies exist in aquatic animals. Research using risk methods has assessed routes of introduction of aquatic animal pathogens to facilitate safe trade (e.g. import risk analyses) and support biosecurity. Epidemiological studies of risk factors for disease in aquaculture (most notably Atlantic salmon farming) have effectively supported control measures. Methods developed for terrestrial livestock diseases (e.g. risk-based surveillance) could improve the capacity of aquatic animal surveillance systems to detect disease incursions and emergence. The study of disease in wild populations presents many challenges and the judicious use of theoretical models offers some solutions. Models, parameterised from observational studies of host pathogen interactions, have been used to extrapolate estimates of impacts on the individual to the population level. These have proved effective in estimating the likely impact of parasite infections on wild salmonid populations in Switzerland and Canada (where the importance of farmed salmon as a reservoir of infection was investigated). A lack of data is often the key constraint in the application of new approaches to surveillance and modelling. The need for epidemiological approaches to protect aquatic animal health will inevitably increase in the face of the combined challenges of climate change, increasing anthropogenic pressures, limited water sources and the growth in aquaculture. Table of contents 1 Introduction 4 2 The development of aquatic epidemiology 7 3 Transboundary and emerging diseases 9 3.1 Import risk analysis (IRA) 10 3.2 Aquaculture and disease emergence 11 3.3 Climate

Reevaluation of epidemiological data demonstrates that it is consistent with cross-immunity among human papillomavirus types.

PubMed

Durham, David P; Poolman, Eric M; Ibuka, Yoko; Townsend, Jeffrey P; Galvani, Alison P

2012-10-01

The degree of cross-immunity between human papillomavirus (HPV) types is fundamental both to the epidemiological dynamics of HPV and to the impact of HPV vaccination. Epidemiological data on HPV infections has been repeatedly interpreted as inconsistent with cross-immunity. We reevaluate the epidemiological data using a model to determine the odds ratios of multiple to single infections expected in the presence or absence of cross-immunity. We simulate a virtual longitudinal survey to determine the effect cross-immunity has on the prevalence of multiple infections. We calibrate our model to epidemiological data and estimate the extent of type replacement following vaccination against specific HPV types. We find that cross-immunity can produce odds ratios of infection comparable with epidemiological observations. We show that the sample sizes underlying existing surveys have been insufficient to identify even intense cross-immunity. We also find that the removal of HPV type 16, type 18, and types 6 and 11 would increase the prevalence of nontargeted types by 50%, 29%, and 183%, respectively. Cross-immunity between HPV types is consistent with epidemiological data, contrary to previous interpretations. Cross-immunity may cause significant type replacement following vaccination, and therefore should be considered in future vaccine studies and epidemiological models.

MICA-AIR: A PARTICIPANT-BASED APPROACH TO EXPOSURE ASSESSMENT IN EPIDEMIOLOGIC AND COMMUNITY HEALTH STUDIES

EPA Science Inventory

Objective. Epidemiologic and community health studies of traffic-related air pollution and childhood asthma have been limited by resource intensive exposure assessment techniques. The current study utilized a novel participant-based approach to collect air monitoring data f...

Risk of chronic low-dose selenium overexposure in humans: insights from epidemiology and biochemistry.

PubMed

Vinceti, Marco; Maraldi, Tullia; Bergomi, Margherita; Malagoli, Carlotta

2009-01-01

The latest developments of epidemiologic and biochemical research suggest that current upper limits of intake for dietary selenium and for overall selenium exposure may be inadequate to protect human health. In particular, recent experimental and observational prospective studies indicate a diabetogenic effect of selenium at unexpectedly low levels of intake. Experimental evidence from laboratory studies and veterinary medicine appears to confirm previous epidemiologic observations that selenium overexposure is associated with an increased risk of amyotrophic lateral sclerosis, and a recent large trial indicated no beneficial effect in preventing prostate cancer. Moreover, the pro-oxidant properties of selenium species and the observation that the selenium-containing enzymes glutathione peroxidases are induced by oxidative stress imply that the increase in enzymatic activity induced by this metalloid may represent at least in part a compensatory response. Taken together, the data indicate that the upper safe limit of organic and inorganic selenium intake in humans may be lower than has been thought and that low-dose chronic overexposure to selenium may be considerably more widespread than supposed.

What can we learn from the first community-based epidemiological study on stalking in Germany?

PubMed

Dressing, Harald; Gass, Peter; Kuehner, Christine

2007-01-01

There is a lack of community-based studies on prevalence rates of stalking and the impact of stalking on victims in continental European countries. The authors published the first community-based epidemiological study on stalking in Germany. The purpose of this paper is to discuss possible implications of these epidemiological data for the mental health system, forensic psychiatry and legal regulations in Germany. For these reasons some data of our epidemiological study are outlined and reanalyzed. To examine lifetime and point prevalence rates of stalking, behavioural and psychological consequences for victims and the impact of stalking on current psychological well-being in a German community sample, a postal survey was conducted with 2000 inhabitants randomly selected from Mannheim (response rate 34.2%, n=679). The survey included a stalking questionnaire and the WHO-5 well-being scale. Almost 12% of the respondents reported having been stalked. This study identified a high lifetime prevalence of stalking in the community. Effects on victims' psychological health were significant and there was a high rate of physical (31%) and sexual (19%) violence in the context of stalking. Our data suggest that the phenomenon deserves more attention in future forensic psychiatric research and practice. Implications for forensic psychiatric assessment and treatment of stalkers as well as for management of stalking victims are discussed.

The REporting of studies Conducted using Observational Routinely-collected health Data (RECORD) Statement

PubMed Central

Benchimol, Eric I.; Smeeth, Liam; Guttmann, Astrid; Harron, Katie; Moher, David; Petersen, Irene; Sørensen, Henrik T.; von Elm, Erik; Langan, Sinéad M.

2015-01-01

Routinely collected health data, obtained for administrative and clinical purposes without specific a priori research goals, are increasingly used for research. The rapid evolution and availability of these data have revealed issues not addressed by existing reporting guidelines, such as Strengthening the Reporting of Observational Studies in Epidemiology (STROBE). The REporting of studies Conducted using Observational Routinely collected health Data (RECORD) statement was created to fill these gaps. RECORD was created as an extension to the STROBE statement to address reporting items specific to observational studies using routinely collected health data. RECORD consists of a checklist of 13 items related to the title, abstract, introduction, methods, results, and discussion section of articles, and other information required for inclusion in such research reports. This document contains the checklist and explanatory and elaboration information to enhance the use of the checklist. Examples of good reporting for each RECORD checklist item are also included herein. This document, as well as the accompanying website and message board (http://www.record-statement.org), will enhance the implementation and understanding of RECORD. Through implementation of RECORD, authors, journals editors, and peer reviewers can encourage transparency of research reporting. PMID:26440803

The REporting of studies Conducted using Observational Routinely-collected health Data (RECORD) statement.

PubMed

Benchimol, Eric I; Smeeth, Liam; Guttmann, Astrid; Harron, Katie; Moher, David; Petersen, Irene; Sørensen, Henrik T; von Elm, Erik; Langan, Sinéad M

2015-10-01

Routinely collected health data, obtained for administrative and clinical purposes without specific a priori research goals, are increasingly used for research. The rapid evolution and availability of these data have revealed issues not addressed by existing reporting guidelines, such as Strengthening the Reporting of Observational Studies in Epidemiology (STROBE). The REporting of studies Conducted using Observational Routinely collected health Data (RECORD) statement was created to fill these gaps. RECORD was created as an extension to the STROBE statement to address reporting items specific to observational studies using routinely collected health data. RECORD consists of a checklist of 13 items related to the title, abstract, introduction, methods, results, and discussion section of articles, and other information required for inclusion in such research reports. This document contains the checklist and explanatory and elaboration information to enhance the use of the checklist. Examples of good reporting for each RECORD checklist item are also included herein. This document, as well as the accompanying website and message board (http://www.record-statement.org), will enhance the implementation and understanding of RECORD. Through implementation of RECORD, authors, journals editors, and peer reviewers can encourage transparency of research reporting.

MOSAIC--A Modular Approach to Data Management in Epidemiological Studies.

PubMed

Bialke, M; Bahls, T; Havemann, C; Piegsa, J; Weitmann, K; Wegner, T; Hoffmann, W

2015-01-01

In the context of an increasing number of multi-centric studies providing data from different sites and sources the necessity for central data management (CDM) becomes undeniable. This is exacerbated by a multiplicity of featured data types, formats and interfaces. In relation to methodological medical research the definition of central data management needs to be broadened beyond the simple storage and archiving of research data. This paper highlights typical requirements of CDM for cohort studies and registries and illustrates how orientation for CDM can be provided by addressing selected data management challenges. Therefore in the first part of this paper a short review summarises technical, organisational and legal challenges for CDM in cohort studies and registries. A deduced set of typical requirements of CDM in epidemiological research follows. In the second part the MOSAIC project is introduced (a modular systematic approach to implement CDM). The modular nature of MOSAIC contributes to manage both technical and organisational challenges efficiently by providing practical tools. A short presentation of a first set of tools, aiming for selected CDM requirements in cohort studies and registries, comprises a template for comprehensive documentation of data protection measures, an interactive reference portal for gaining insights and sharing experiences, supplemented by modular software tools for generation and management of generic pseudonyms, for participant management and for sophisticated consent management. Altogether, work within MOSAIC addresses existing challenges in epidemiological research in the context of CDM and facilitates the standardized collection of data with pre-programmed modules and provided document templates. The necessary effort for in-house programming is reduced, which accelerates the start of data collection.

An Application of Epidemiological Modeling to Information Diffusion

NASA Astrophysics Data System (ADS)

McCormack, Robert; Salter, William

Messages often spread within a population through unofficial - particularly web-based - media. Such ideas have been termed "memes." To impede the flow of terrorist messages and to promote counter messages within a population, intelligence analysts must understand how messages spread. We used statistical language processing technologies to operationalize "memes" as latent topics in electronic text and applied epidemiological techniques to describe and analyze patterns of message propagation. We developed our methods and applied them to English-language newspapers and blogs in the Arab world. We found that a relatively simple epidemiological model can reproduce some dynamics of observed empirical relationships.