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‣ Disparity between Multilocus Enzyme Electrophoresis, Microsatellite Markers and Pulsed-Field Gel Electrophoresis in epidemiological tracking of Candida albicans

BORIOLLO, Marcelo Fabiano Gomes; DIAS, Ricardo Antunes; FIORINI, Joao Evangelista; OLIVEIRA, Nelma de Mello Silva; SPOLIDORIO, Denise Madalena Palomari; SOUZA, Henrique Marques Barbosa de; FIGUEIRA, Antonio Vargas de Oliveira; PIZZIRANI-KLEINER, Aline Apa
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
37.096724%
Various molecular systems are available for epidemiological, genetic, evolutionary, taxonomic and systematic studies of innumerable fungal infections, especially those caused by the opportunistic pathogen C. albicans. A total of 75 independent oral isolates were selected in order to compare Multilocus Enzyme Electrophoresis (MLEE), Electrophoretic Karyotyping (EK) and Microsatellite Markers (Simple Sequence Repeats - SSRs), in their abilities to differentiate and group C. albicans isolates (discriminatory power), and also, to evaluate the concordance and similarity of the groups of strains determined by cluster analysis for each fingerprinting method. Isoenzyme typing was performed using eleven enzyme systems: Adh, Sdh, M1p, Mdh, Idh, Gdh, G6pdh, Asd, Cat, Po, and Lap (data previously published). The EK method consisted of chromosomal DNA separation by pulsed-field gel electrophoresis using a CHEF system. The microsatellite markers were investigated by PCR using three polymorphic loci: EF3, CDC3, and HIS3. Dendrograms were generated by the SAHN method and UPGMA algorithm based on similarity matrices (S(SM)). The discriminatory power of the three methods was over 95%, however a paired analysis among them showed a parity of 19.7-22.4% in the identification of strains. Weak correlation was also observed among the genetic similarity matrices (S(SM)(MLEE) x S(SM)(EK) x S(SM)(SSRs)). Clustering analyses showed a mean of 9 +/- 12.4 isolates per cluster (3.8 +/- 8 isolates/taxon) for MLEE...

‣ "Diagnóstico da doença de Chagas em bancos de sangue: linfoproliferação, detecção de anticorpos e estudo epidemiológico em indivíduos com provas sorológicas inconclusivas" ; Diagnostic of Chagas disease in blood banks: lymphoproliferation, antibodies detection and epidemiological data in individuals with inconclusive serology

Yamamoto, Celia Regina Furucho
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 27/03/2006 Português
Relevância na Pesquisa
36.9092%
O objetivo deste estudo foi avaliar a contribuição de linfoproliferação (1 parâmetro) em associação a provas sorológicas de alto desempenho (4 parâmetros), estudo epidemiológico (1) e parasitológico (1) em indivíduos com sorologia convencional inconclusiva para a doença de Chagas. Mostramos que o diagnóstico de doença de Chagas é provável quando 3 ou mais desses parâmetros são positivos em 7 (15/73). A combinação: TESA-blot e linfoproliferação positivos revelou-se útil diante de antecedentes epidemiológicos positivos; This study aims to evaluate the contribution of lymphoproliferation (1 parameter) in association with high performance serological tests (4), epidemiological data (1) and parasitological tests (1) for Chagas disease in patients with inconclusive conventional serological tests. We showed that this diagnosis is probable in individuals presenting > three positive of these 7 parameters (15 of 73 individuals). The combination of TESA-blot, lymphoproliferation was useful when epidemiological data were positive

‣ Vigilância epidemiológica de endoftalmite e síndrome tóxica do segmento anterior após cirurgias de catarata: identificação e seleção de marcadores; Epidemiological surveillance of endophthalmitis and Toxic Anterior Segment Syndrome after cataract surgery: identification and selection of markers

Luz, Reginaldo Adalberto de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 28/11/2013 Português
Relevância na Pesquisa
36.95643%
Introdução: Entre os possíveis Eventos Adversos (EA) mais importantes após cirurgias de catarata estão a endoftalmite, termo que define a infecção intraocular e a Síndrome Tóxica do Segmento Anterior (TASS), que consiste na reação inflamatória aguda pós-cirúrgica. Contudo, um sistema de vigilância epidemiológica (VE) da ocorrência destes EA não é uma realidade no Brasil, o que dificulta o monitoramento da incidência, detecção precoce de surtos e as medidas de prevenção. Devido as especificidades no campo da oftalmologia, nem sempre o enfermeiro está suficientemente instrumentalizado para contribuir na detecção e monitoramento de casos. A identificação de marcadores destes EA factíveis de serem acompanhados por este profissional irá favorecer o desenvolvimento de um sistema de VE. Objetivo: Identificar os marcadores mais adequados para o diagnóstico epidemiológico de EA após cirurgias de catarata visando à instituição de um sistema de VE específico. Métodos: Trata-se de um estudo longitudinal de série de casos de pacientes submetidos a cirurgias de catarata, realizado em duas etapas. Etapa I: abordagem retrospectiva por meio de revisão de prontuários dos pacientes com diagnóstico de EA (21 casos) no período de abril/2010 a fevereiro/2013. Etapa II: abordagem prospectiva por meio de revisão de prontuários dos pacientes submetidos à cirurgia de catarata sem EA (309 controles) nos meses de maio e junho/ 2013. A amostra baseou-se em um teste de proporções entre duas amostras assumindo que a amostra de controles seria 15 vezes maior que a de casos para detectar uma diferença de pelo menos 35 pontos percentuais na incidência da apresentação de características clínicas entre os dois grupos com erro tipo I de 5% e poder do teste de 90%. As variáveis pesquisadas foram os sinais e sintomas característicos do pós-operatório de cirurgias de catarata bem como informações demográficas e clínicas destes pacientes. Foi realizada estatística descritiva por meio de frequências relativas e absolutas. Resultados: Pacientes com EA apresentaram o diagnóstico de endoftalmite e TASS...

‣ Epidemiological methods for research with drug misusers: review of methods for studying prevalence and morbidity

Dunn,John; Ferri,Cleusa P.
Fonte: Faculdade de Saúde Pública da Universidade de São Paulo Publicador: Faculdade de Saúde Pública da Universidade de São Paulo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/1999 Português
Relevância na Pesquisa
57.114766%
Epidemiological studies of drug misusers have until recently relied on two main forms of sampling: probability and convenience. The former has been used when the aim was simply to estimate the prevalence of the condition and the latter when in depth studies of the characteristics, profiles and behaviour of drug users were required, but each method has its limitations. Probability samples become impracticable when the prevalence of the condition is very low, less than 0.5% for example, or when the condition being studied is a clandestine activity such as illicit drug use. When stratified random samples are used, it may be difficult to obtain a truly representative sample, depending on the quality of the information used to develop the stratification strategy. The main limitation of studies using convenience samples is that the results cannot be generalised to the whole population of drug users due to selection bias and a lack of information concerning the sampling frame. New methods have been developed which aim to overcome some of these difficulties, for example, social network analysis, snowball sampling, capture-recapture techniques, privileged access interviewer method and contact tracing. All these methods have been applied to the study of drug misuse. The various methods are described and examples of their use given...

‣ Handling random errors and biases in methods used for short-term dietary assessment

Rossato,Sinara L; Fuchs,Sandra C
Fonte: Faculdade de Saúde Pública da Universidade de São Paulo Publicador: Faculdade de Saúde Pública da Universidade de São Paulo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2014 Português
Relevância na Pesquisa
36.88995%
Epidemiological studies have shown the effect of diet on the incidence of chronic diseases; however, proper planning, designing, and statistical modeling are necessary to obtain precise and accurate food consumption data. Evaluation methods used for short-term assessment of food consumption of a population, such as tracking of food intake over 24h or food diaries, can be affected by random errors or biases inherent to the method. Statistical modeling is used to handle random errors, whereas proper designing and sampling are essential for controlling biases. The present study aimed to analyze potential biases and random errors and determine how they affect the results. We also aimed to identify ways to prevent them and/or to use statistical approaches in epidemiological studies involving dietary assessments.

‣ Reporting of occupational and environmental research: use and misuse of statistical and epidemiological methods

Rushton, L.
Fonte: BMJ Group Publicador: BMJ Group
Tipo: Artigo de Revista Científica
Publicado em /01/2000 Português
Relevância na Pesquisa
46.88995%
OBJECTIVES—To report some of the most serious omissions and errors which may occur in papers submitted to Occupational and Environmental Medicine, and to give guidelines on the essential components that should be included in papers reporting results from studies of occupational and environmental health.
METHODS—Since 1994 Occupational and Environmental Medicine has used a panel of medical statisticians to review submitted papers which have a substantial statistical content. Although some studies may have genuine errors in their design, execution, and analysis, many of the problems identified during the reviewing process are due to inadequate and incomplete reporting of essential aspects of a study. This paper outlines some of the most important errors and omissions that may occur. Observational studies are often the preferred choice of design in occupational and environmental medicine. Some of the issues relating to design, execution, and analysis which should be considered when reporting three of the most common observational study designs, cross sectional, case-control, and cohort are described. An illustration of good reporting practice is given for each. Various mathematical modelling techniques are often used in the analysis of these studies...

‣ Development of an asthma specific job exposure matrix and its application in the epidemiological study of genetics and environment in asthma (EGEA)

Kennedy, S.; Le Moual, N.; Choudat, D.; Kauffmann, F.
Fonte: BMJ Group Publicador: BMJ Group
Tipo: Artigo de Revista Científica
Publicado em /09/2000 Português
Relevância na Pesquisa
36.9092%
OBJECTIVES—To develop a method suitable for estimating exposure risks in population studies of asthma from job titles and international codes, by combining a new job exposure matrix (JEM) with the expert judgement approach. The method was applied in the French epidemiological study of the genetics and environment in asthma (EGEA).
METHODS—The JEM contains 22 exposure groups including 18 high risk groups based on known risk factors for occupational asthma, divided into high molecular weight agents, low molecular weight agents, and mixed environments. After applying the JEM to job codes, exposure estimates for each subject were re-evaluated by examining job title texts. Three high risk exposure estimates for asthma were compared: firstly, applying the JEM to original codes (from different coders in each study centre); secondly, applying the JEM to revised codes (from one experienced coder); and thirdly, after reviewing JEM exposure estimates in the light of job title texts.
RESULTS—The study comprised 173 cases with asthma and 285 controls (age 18-65). Odds ratios (ORs) for asthma for high risk jobs were 1.0 (95% confidence interval (95% CI) 0.6 to 1.7), applying the JEM to original codes; 1.4 (95% CI 0.8 to 2.3), applying the JEM to revised codes; and 1.7 (95% CI 1.1 to 2.7)...

‣ Impact of environmental inequity on health outcome: where is the epidemiological evidence?

René, A. A.; Daniels, D. E.; Martin, S. A.
Fonte: National Medical Association Publicador: National Medical Association
Tipo: Artigo de Revista Científica
Publicado em /06/2000 Português
Relevância na Pesquisa
37.008623%
A significant amount of evidence reveals a presence of environmental inequity. Although there is a disproportionate distribution of waste treatment, storage and disposal facilities, and chemical and manufacturing plants in minority and low-income communities in the United States, little research has been devoted to show any associations based on analytic epidemiological methods. To date, attempts to quantify health disparities have included demographic data, race, sex, income, other socioeconomic factors, and broad symptomatic survey instruments. To study this, we examined the latest epidemiological evidence documenting the existence of adverse health impacts resulting from environmental inequity. We observed that the overwhelming majority of studies were descriptive in nature and lacked comparison populations. As a result, we believe that further research based on analytic epidemiological methods would further contribute to the determination of the cause-effect relationship between environmental exposure and health outcome.

‣ Measuring socio-economic position for epidemiological studies in low- and middle-income countries: a methods of measurement in epidemiology paper

Howe, Laura D; Galobardes, Bruna; Matijasevich, Alicia; Gordon, David; Johnston, Deborah; Onwujekwe, Obinna; Patel, Rita; Webb, Elizabeth A; Lawlor, Debbie A; Hargreaves, James R
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.9092%
Much has been written about the measurement of socio-economic position (SEP) in high-income countries (HIC). Less has been written for an epidemiology, health systems and public health audience about the measurement of SEP in low- and middle-income countries (LMIC). The social stratification processes in many LMIC—and therefore the appropriate measurement tools—differ considerably from those in HIC. Many measures of SEP have been utilized in epidemiological studies; the aspects of SEP captured by these measures and the pathways through which they may affect health are likely to be slightly different but overlapping. No single measure of SEP will be ideal for all studies and contexts; the strengths and limitations of a given indicator are likely to vary according to the specific research question. Understanding the general properties of different indicators, however, is essential for all those involved in the design or interpretation of epidemiological studies. In this article, we describe the measures of SEP used in LMIC. We concentrate on measures of individual or household-level SEP rather than area-based or ecological measures such as gross domestic product. We describe each indicator in terms of its theoretical basis, interpretation...

‣ A Comparison of Three Methods to Measure Asthma in Epidemiologic Studies: Results from the Danish National Birth Cohort

Hansen, Susanne; Strøm, Marin; Maslova, Ekaterina; Mortensen, Erik Lykke; Granström, Charlotta; Olsen, Sjurdur F.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
46.69313%
Asthma is a heterogeneous outcome and how the condition should be measured to best capture clinically relevant disease in epidemiologic studies remains unclear. We compared three methods of measuring asthma in the Danish National Birth Cohort (n>50.000). When the children were 7 years old, the prevalence of asthma was estimated from a self-administered questionnaire using parental report of doctor diagnoses, ICD-10 diagnoses from a population-based hospitalization registry, and data on anti-asthmatic medication from a population-based prescription registry. We assessed the agreement between the methods using kappa statistics. Highest prevalence of asthma was found using the prescription registry (32.2%) followed by the self-report (12.0%) and the hospitalization registry (6.6%). We found a substantial non-overlap between the methods (kappa = 0.21–0.38). When all three methods were combined the asthma prevalence was 3.6%. In conclusion, self-reported asthma, ICD-10 diagnoses from a hospitalization registry and data on anti-asthmatic medication use from a prescription registry lead to different prevalences of asthma in the same cohort of children. The non-overlap between the methods may be due to different abilities of the methods to identify cases with different phenotypes...

‣ Simple Methods of Determining Confidence Intervals for Functions of Estimates in Published Results

Fitzmaurice, Garrett; Lipsitz, Stuart; Natarajan, Sundar; Gawande, Atul; Sinha, Debajyoti; Greenberg, Caprice; Giovannucci, Edward
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
46.618237%
Often, the reader of a published paper is interested in a comparison of parameters that has not been presented. It is not possible to make inferences beyond point estimation since the standard error for the contrast of the estimated parameters depends upon the (unreported) correlation. This study explores approaches to obtain valid confidence intervals when the correlation is unknown. We illustrate three proposed approaches using data from the National Health Interview Survey. The three approaches include the Bonferroni method and the standard confidence interval assuming (most conservative) or (when the correlation is known to be non-negative). The Bonferroni approach is found to be the most conservative. For the difference in two estimated parameter, the standard confidence interval assuming yields a 95% confidence interval that is approximately 12.5% narrower than the Bonferroni confidence interval; when the correlation is known to be positive, the standard 95% confidence interval assuming is approximately 38% narrower than the Bonferroni. In summary, this article demonstrates simple methods to determine confidence intervals for unreported comparisons. We suggest use of the standard confidence interval assuming if no information is available or if the correlation is known to be non-negative.

‣ Handling random errors and biases in methods used for short-term dietary assessment

Rossato, Sinara L; Fuchs, Sandra C
Fonte: Faculdade de Saúde Pública da Universidade de São Paulo Publicador: Faculdade de Saúde Pública da Universidade de São Paulo
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.88995%
Epidemiological studies have shown the effect of diet on the incidence of chronic diseases; however, proper planning, designing, and statistical modeling are necessary to obtain precise and accurate food consumption data. Evaluation methods used for short-term assessment of food consumption of a population, such as tracking of food intake over 24h or food diaries, can be affected by random errors or biases inherent to the method. Statistical modeling is used to handle random errors, whereas proper designing and sampling are essential for controlling biases. The present study aimed to analyze potential biases and random errors and determine how they affect the results. We also aimed to identify ways to prevent them and/or to use statistical approaches in epidemiological studies involving dietary assessments.

‣ Reporting on methods of subgroup analysis in clinical trials: a survey of four scientific journals

Moreira Jr.,E.D.; Stein,Z.; Susser,E.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2001 Português
Relevância na Pesquisa
46.527295%
Results of subgroup analysis (SA) reported in randomized clinical trials (RCT) cannot be adequately interpreted without information about the methods used in the study design and the data analysis. Our aim was to show how often inaccurate or incomplete reports occur. First, we selected eight methodological aspects of SA on the basis of their importance to a reader in determining the confidence that should be placed in the author's conclusions regarding such analysis. Then, we reviewed the current practice of reporting these methodological aspects of SA in clinical trials in four leading journals, i.e., the New England Journal of Medicine, the Journal of the American Medical Association, the Lancet, and the American Journal of Public Health. Eight consecutive reports from each journal published after July 1, 1998 were included. Of the 32 trials surveyed, 17 (53%) had at least one SA. Overall, the proportion of RCT reporting a particular methodological aspect ranged from 23 to 94%. Information on whether the SA preceded/followed the analysis was reported in only 7 (41%) of the studies. Of the total possible number of items to be reported, NEJM, JAMA, Lancet and AJPH clearly mentioned 59, 67, 58 and 72%, respectively. We conclude that current reporting of SA in RCT is incomplete and inaccurate. The results of such SA may have harmful effects on treatment recommendations if accepted without judicious scrutiny. We recommend that editors improve the reporting of SA in RCT by giving authors a list of the important items to be reported.

‣ Changing non-participation in epidemiological studies of older people: evidence from the Cognitive Function and Ageing Study I and II

Gao, Lu; Green, Emma; Barnes, Linda E.; Brayne, Carol; Matthews, Fiona E.; Robinson, Louise; Arthur, Antony
Fonte: OUP Publicador: OUP
Tipo: Article; published version
Português
Relevância na Pesquisa
37.075977%
This is the final version. It is available from Oxford University Press via http://dx.doi.org/10.1093/ageing/afv101; Background: non-participation in epidemiological studies threatens the generalisability of findings. Objective: to investigate the change in non-participation between the Medical Research Council Cognitive Function and Ageing Study (CFAS) I and II. Design: a comparison of two epidemiological studies of older people using identical methods. Setting: three geographical areas of the United Kingdom. Subjects: older people aged 65 years and over. Methods: the two studies were conducted approximately two decades apart between 1989 and 1994 (CFAS I) and between 2008 and 2011 (CFAS II). Random samples were drawn from primary care lists. We compared demographic factors associated with non-participation. Results: non-participation in CFAS II was higher than in CFAS I (45.3 versus 18.3%). After adjustment for confounders, in both CFAS I and CFAS II, women were more likely to decline to take part (CFAS I: odds ratio (OR) 1.3 95% confidence interval (CI) 1.2 to 1.4; CFAS II: 1.1 95% CI 1.1 to 1.2). Deprivation was associated with non-participation in both studies (highest versus lowest Townsend deprivation quintile...

‣ Amostragem domiciliar contínua em estudos epidemiológicos e no ensino; Continuous household sampling for epidemiological research and for teaching purposes

Carvalheiro, José da Rocha; Sanches, Odécio
Fonte: Universidade de São Paulo. Faculdade de Saúde Pública Publicador: Universidade de São Paulo. Faculdade de Saúde Pública
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/09/1979 Português
Relevância na Pesquisa
36.907788%
Descreve-se um sistema contínuo de levantamento de condições de saúde, por entrevistas domiciliárias, operando em Ribeirão Preto (SP) desde 1974. Comentam-se as vantagens quanto à sua utilização na investigação de problemas específicos surgidos nesse período, bem como a sua utilização no ensino.; The use of adequate populational-base survey is frequently impossible in epidemiological studies. Special studies are made among particular groups of individuals to investigate simultaneously the presence of both the factor and the disease. In these studies it is obviously important to use adequate sampling techniques. A system of continuous household sampling is described, designed to perform, simultaneously, epidemiological research, health system monitoring and to serve as a basis for courses on sampling techniques and epidemiological methods. In the municipality of Ribeirão Preto, S. Paulo, Brazil a household sampling system has been in operation since 1974, using a master sample of 8500 households. Every two weeks, 380 households are visited and information is gathered about diseases, accidents, and the use of health services. Special epidemiological research is introduced when necessary. Future development includes the use of standardized questionnaires and physical and laboratory examinations of the people interviewed.

‣ Método de captura e recaptura: nova metodologia para pesquisas epidemiológicas; Capture-recapture: a new methodology for epidemiological research

Dunn, John; Andreoli, Sérgio Baxter
Fonte: Universidade de São Paulo. Faculdade de Saúde Pública Publicador: Universidade de São Paulo. Faculdade de Saúde Pública
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; ; Formato: application/pdf
Publicado em 01/12/1994 Português
Relevância na Pesquisa
36.9092%
O método de captura e recaptura, embora não seja novo, tem sido pouco usado em estudos epidemiológicos. Trata-se de método bem adaptável e adequado para estudar populações incomuns ou esquivas, como usuários de drogas endovenosas. Tem sido usado para estudar populações diversas como prostitutas que trabalham na rua ou volume de células vermelhas no homem. Permite ainda estimar a incidência e a prevalência de doenças de forma mais precisa do que os métodos tradicionais e com uma melhor relação custo-benefício. Devido à sua relevância dentro do campo da epidemiologia, decidiu-se realizar uma revisão sobre esse método, enfocando a história, as principais aplicações e apontando as suposições teóricas que o fundamentam. Seu potencial para futuras pesquisas epidemiológicas é promissor.; Although capture-recapture method is not new, their use in epidemiological studies has so far been limited. The method was developed by animal ecologists to estimate the size of various species populations, but in recent years it has been used to measure the incidence and prevalence of a variety of non-communicable diseases. Capture-recapture allows more accurate estimates to be made than is the case with traditional methods and is more cost-effective. The method is ideally suited to studying rare or elusive populations...

‣ Systematic review about methods of energy expenditure and energy intake in children and adolescents; Revisão sistemática sobre métodos de determinação de gasto e consumo energéticos em crianças e adolescentes

Frainer, Deivis Elton Schilickmann; Instituto de Saúde Coletiva da Universidade Federal da Bahia. Brasil.; Adami, Fernando; Faculdade de Saúde Pública da Universidade de São Paulo. São Paulo. Brasil; Vasconcelos, Francisco de Assis Guedes de; Univers
Fonte: Universidade Federal de Santa Catarina. Florianópolis, SC. Brasil Publicador: Universidade Federal de Santa Catarina. Florianópolis, SC. Brasil
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; "Avaliado por Pares","Artigo Solicitado"; ; "Avaliado por Pares", "Artigo Solicitado"; Bibliográfica Formato: application/pdf; application/pdf
Publicado em 18/07/2008 Português
Relevância na Pesquisa
37.281538%
http://dx.doi.org/10.5007/1980-0037.2008v10n2p197The objective of this systematic review was to identify, describe and analyze methods used for determining energy expenditure and energy intake in clinical and population-based epidemiological studies. The study population was made up of children and adolescents aged from 6 to 18 years. The articles were identifi ed by means of searching the Medline database. A total of 141 articles were identifi ed, 32 of which were selected. From these, 10 articles were chosen, 6 of which were clinical epidemiological studies and 4 were populational epidemiological studies. The methods used to determine energy expenditure in the clinical studies were doubly labeled water and indirect calorimetry. In the populational studies, questionnaires on physical activity were used to determine the energy expended during physical activity. The methods used to evaluate nutritional intake, both in the clinical and populational epidemiological studies, were 24-hour dietary recalls, food records and food frequency questionnaires. The review goes on to discuss questions such as the manner in which these methods are employed and their validation and adaptation for populations of children and adolescents. It is concluded that care must be taken with the methodological aspects of epidemiological study design in order to avoid introducing bias to results and limiting conclusions.; O objetivo dessa revisão sistemática foi identifi car...

‣ Epidemiological methods for research with drug misusers: review of methods for studying prevalence and morbidity

Dunn,John; Ferri,Cleusa P.
Fonte: Faculdade de Saúde Pública da Universidade de São Paulo Publicador: Faculdade de Saúde Pública da Universidade de São Paulo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/1999 Português
Relevância na Pesquisa
57.114766%
Epidemiological studies of drug misusers have until recently relied on two main forms of sampling: probability and convenience. The former has been used when the aim was simply to estimate the prevalence of the condition and the latter when in depth studies of the characteristics, profiles and behaviour of drug users were required, but each method has its limitations. Probability samples become impracticable when the prevalence of the condition is very low, less than 0.5% for example, or when the condition being studied is a clandestine activity such as illicit drug use. When stratified random samples are used, it may be difficult to obtain a truly representative sample, depending on the quality of the information used to develop the stratification strategy. The main limitation of studies using convenience samples is that the results cannot be generalised to the whole population of drug users due to selection bias and a lack of information concerning the sampling frame. New methods have been developed which aim to overcome some of these difficulties, for example, social network analysis, snowball sampling, capture-recapture techniques, privileged access interviewer method and contact tracing. All these methods have been applied to the study of drug misuse. The various methods are described and examples of their use given...

‣ The effectiveness of HIV prevention and the epidemiological context

Grassly,Nicholas C.; Garnett,Geoff P.; Schwartländer,Bernhard; Gregson,Simon; Anderson,Roy M.
Fonte: World Health Organization Publicador: World Health Organization
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2001 Português
Relevância na Pesquisa
36.95643%
Planning an intervention to prevent infections with the human immunodeficiency virus (HIV) should be guided by local epidemiological and socioeconomic conditions. The socioeconomic setting and existing public service capacity determine whether an intervention can have a significant outcome in terms of a reduction in a defined risk. The epidemiological context determines whether such risk reduction translates into a measurable impact on HIV incidence. Measurement of variables describing the epidemiological context can be used to determine the local suitability of interventions, thereby guiding planners and policy-makers in their choice of intervention. Such measurements also permit the retrospective analysis of the impact of interventions where HIV incidence was not recorded. The epidemiological context is defined for four different categories of intervention, shown to be effective in lower-income countries by randomized controlled trials. Appropriate indicators for the epidemiological context and methodological guidelines for their measurement are proposed. Their use in the transfer of a successful intervention from one context to another and in scaling up the effort to control HIV infection is explored. These indicators should provide a useful resource for those involved in planning HIV prevention interventions.

‣ Handling random errors and biases in methods used for short-term dietary assessment

Rossato,Sinara L; Fuchs,Sandra C
Fonte: Faculdade de Saúde Pública da Universidade de São Paulo Publicador: Faculdade de Saúde Pública da Universidade de São Paulo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2014 Português
Relevância na Pesquisa
36.88995%
Epidemiological studies have shown the effect of diet on the incidence of chronic diseases; however, proper planning, designing, and statistical modeling are necessary to obtain precise and accurate food consumption data. Evaluation methods used for short-term assessment of food consumption of a population, such as tracking of food intake over 24h or food diaries, can be affected by random errors or biases inherent to the method. Statistical modeling is used to handle random errors, whereas proper designing and sampling are essential for controlling biases. The present study aimed to analyze potential biases and random errors and determine how they affect the results. We also aimed to identify ways to prevent them and/or to use statistical approaches in epidemiological studies involving dietary assessments.