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‣ Arg72Pro TP53 polymorphism and cancer susceptibility: a comprehensive meta-analysis of 302 case-control studies

FRANCISCO, Guilherme; MENEZES, Paulo Rossi; ELUF-NETO, Jose; CHAMMAS, Roger
Fonte: WILEY-BLACKWELL Publicador: WILEY-BLACKWELL
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
87.25304%
Arg72Pro is a common polymorphism in TP53, showing differences in its biological functions. Case-control studies have been performed to elucidate the role of Arg72Pro in cancer, although the results are conflicting and heterogeneous. Here, we analyzed pooled data from case-control studies to determine the role of Arg72Pro in different cancer sites. We performed a systematic review and meta-analysis of 302 case-control studies that analyzed Arg72Pro in cancer susceptibility. Odds ratios were estimated for different tumor sites using distinct genetic models, and the heterogeneity between studies was explored using I(2) values and meta-regression. We adopted quality criteria to classify the studies. Subgroup analyses were done for tumor sites according to ethnicity, histological, and anatomical sites. Results indicated that Arg72Pro is associated with higher susceptibility to cancer in some tumor sites, mainly hepatocarcinoma. For some tumor sites, quality of studies was associated with the size of genetic association, mainly in cervical, head and neck, gastric, and lung cancer. However, study quality did not explain the observed heterogeneity substantially. Meta-regression showed that ethnicity, allelic frequency and genotyping method were responsible for a substantial part of the heterogeneity observed. Our results suggest ethnicity and histological and anatomical sites may modulate the penetrance of Arg72Pro in cancer susceptibility. This meta-analysis denotes the importance for more studies with good quality and that the covariates responsible for heterogeneity should be controlled to obtain a more conclusive response about the function of Arg72Pro in cancer.; Conselho Nacional de Desenvolvimento Cientifico e Tecnologico-CNPq Brasilia...

‣ Freqüência de câncer de próstata em pacientes transplantados renais: estudo caso-controle; Frequency of prostate cancer in patients submitted to renal transplantation: a case-control study

Alvarez, Gilberto Antunes
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 03/09/2007 Português
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77.02771%
INTRODUÇÃO: Os pacientes submetidos a transplante renal estão sujeitos a um risco muito aumentado para câncer, porém inexistem dados concretos quanto a maior chance de tumor de próstata nesses pacientes. Neste estudo, avaliou-se a freqüência de câncer de próstata em transplantados renais comparada à de pacientes-controle, bem como a sua relação com etnia, antecedentes familiares, toque prostático, níveis de PSA e aos esquemas de imunossupressão nos pacientes transplantados renais. MÉTODOS: Neste estudo caso-controle realizado entre agosto de 2004 e junho de 2006 comparou-se a freqüência de câncer de próstata entre pacientes transplantados renais (n=119) há mais de um ano e pacientes do grupo-controle (n=184), bem como as variáveis: etnia, idade, presença de antecedentes familiares, escore internacional de sintomas prostáticos, toque retal, níveis de PSA e índice de massa corpórea (IMC). Os pacientes com PSA e/ou toque retal alterado foram submetidos à biópsias prostáticas guiadas por ultra-som transretal. As comparações das freqüências entre os dois grupos deram-se através das variáveis: idade, etnia, presença de antecedentes familiares, toque suspeito e valores de PSA>2,5ng/mL e >4,0ng/mL. Avaliou-se também a relação entre os tipos e doses de imunossupressor e presença de câncer. RESULTADOS: Não houve maior freqüência de tumor de próstata em transplantados (6...

‣ Hospital visitors as controls in case-control studies

Mendonça,Gulnar Azevedo S; Eluf-Neto,José
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 01/10/2001 Português
Relevância na Pesquisa
97.08487%
OBJECTIVE: Selecting controls is one of the most difficult tasks in the design of case-control studies. Hospital controls may be inadequate and random controls drawn from the base population may be unavailable. The aim was to assess the use of hospital visitors as controls in a case-control study on the association of organochlorinated compounds and other risk factors for breast cancer conducted in the main hospital of the "Instituto Nacional de Câncer" -- INCA (National Cancer Institute) in Rio de Janeiro (Brazil). METHODS: The study included 177 incident cases and 377 controls recruited among female visitors. Three different models of control group composition were compared: Model 1, with all selected visitors; Model 2, excluding women visiting relatives with breast cancer; and Model 3, excluding all women visiting relatives with any type of cancer. Odds ratios (OR) and 95% confidence intervals were calculated to test the associations. RESULTS: Age-adjusted OR for breast cancer associated with risk factors other than family history of cancer, except smoking and breast size, were similar in the three models. Regarding family history of all cancers, except for breast cancer, there was a decreased risk in Models 1 and 2, while in Model 3 there was an increased risk...

‣ Retreatment in leprosy: a case-control study

Ximenes,Ricardo Arraes Alencar; Gallo,Maria Eugênia Novinsk; Brito,Maria de Fátima de Medeiros
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 01/08/2007 Português
Relevância na Pesquisa
77.008164%
OBJECTIVE: To assess risk factors for retreatment of leprosy patients. METHODS: A case-control study with patients from two reference care units in Recife, northeastern Brazil, in 2003. The case group included retreated patients (N=155) and the control group comprised those patients who were not retreated (N=155) matched by year of diagnosis and health care unit. Univariate and multivariate analyses were conducted to test the associations and odds ratios and related 95% confidence intervals were estimated. RESULTS: The following factors were found to be significantly associated (p<0.05) with retreatment: occurrence of adverse immunological reactions after treatment completion (OR=2.3; 95% CI=1.18;4.83), final bacterial index > 1 (OR=6.43; 95% CI=1.67;24.74), therapeutic regimen consisting of sulfone monotherapy (OR=10; 95% CI=0.01;0.78) and reports of household contacts (OR=2.2; 95% CI=0.24;0.85). CONCLUSIONS: The study findings reinforce that the use of dapsone monotherapy should be discontinued, and highlight the need for epidemiological monitoring of specific groups of leprosy patients after treatment completion through periodical clinical and laboratory evaluation. Further studies to explore the association between final bacterial index and retreatment are strongly recommended.

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

Goi,Pedro Domingues; Goi,Julia Domingues; Cordini,Kariny Larissa; Ceresér,Keila Mendes; Rocha,Neusa Sica da
Fonte: Associação Paulista de Medicina - APM Publicador: Associação Paulista de Medicina - APM
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2014 Português
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97.42873%
CONTEXT AND OBJECTIVE: 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. DESIGN AND SETTING: Descriptive study on psychiatric papers published in Brazilian journals, within the Postgraduate Medical Program on Psychiatry, at Universidade Federal do Rio Grande do Sul. METHODS: 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. RESULTS: Sixteen case-control studies were identified, of which eleven (68.75%) were in psychiatry-focused journals. From analysis using the STROBE statement...

‣ Estimating Risk and Rate Levels, Ratios and Differences in Case-Control Studies

King, Gary; Zeng, Langche
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
87.04292%
Classic (or ‘cumulative’) case-control sampling designs do not admit inferences about quantities of interest other than risk ratios, and then only by making the rare events assumption. Probabilities, risk di erences and other quantities cannot be computed without knowledge of the population incidence fraction. Similarly, density (or ‘risk set’) case-control sampling designs do not allow inferences about quantities other than the rate ratio. Rates, rate di erences, cumulative rates, risks, and other quantities cannot be estimated unless auxiliary information about the underlying cohort such as the number of controls in each full risk set is available. Most scholars who have considered the issue recommend reporting more than just risk and rate ratios, but auxiliary population information needed to do this is not usually available. We address this problem by developing methods that allow valid inferences about all relevant quantities of interest from either type of case-control study when completely ignorant of or only partially knowledgeable about relevant auxiliary population information.; Government

‣ A Case-Control Study of Peripheral Blood Mitochondrial DNA Copy Number and Risk of Renal Cell Carcinoma

Purdue, Mark P.; Hofmann, Jonathan N.; Colt, Joanne S.; Hoxha, Mirjam; Ruterbusch, Julie J.; Davis, Faith G.; Rothman, Nathaniel; Wacholder, Sholom; Schwartz, Kendra L.; Baccarelli, Andrea; Chow, Wong-Ho
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
77.050127%
Background: Low mitochondrial DNA (mtDNA) copy number is a common feature of renal cell carcinoma (RCC), and may influence tumor development. Results: from a recent case-control study suggest that low mtDNA copy number in peripheral blood may be a marker for increased RCC risk. In an attempt to replicate that finding, we measured mtDNA copy number in peripheral blood DNA from a U.S. population-based case-control study of RCC. Methodology/Principal Findings: Relative mtDNA copy number was measured in triplicate by a quantitative real-time PCR assay using DNA extracted from peripheral whole blood. Cases (n = 603) had significantly lower mtDNA copy number than controls (n = 603; medians 0.85, 0.91 respectively; P = 0.0001). In multiple logistic regression analyses, the lowest quartile of mtDNA copy number was associated with a 60% increase in RCC risk relative to the highest quartile (OR = 1.6, 95% CI = 1.1–2.2; Ptrend = 0.009). This association remained in analyses restricted to cases treated by surgery alone (OR Q1 = 1.4, 95% CI = 1.0–2.1) and to localized tumors (2.0, 1.3–2.8). Conclusions/Significance: Our findings from this investigation, to our knowledge the largest of its kind, offer important confirmatory evidence that low mtDNA copy number is associated with increased RCC risk. Additional research is needed to assess whether the association is replicable in prospective studies.

‣ Informed Conditioning on Clinical Covariates Increases Power in Case-Control Association Studies

Zaitlen, Noah; Lindström, Sara; Pasaniuc, Bogdan; Cornelis, Marilyn; Genovese, Giulio; Pollack, Samuela; Barton, Anne; Bickeböller, Heike; Bowden, Donald W.; Eyre, Steve; Freedman, Barry I.; Friedman, David J.; Field, John K.; Groop, Leif; Haugen, Aage;
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
87.47069%
Genetic case-control association studies often include data on clinical covariates, such as body mass index (BMI), smoking status, or age, that may modify the underlying genetic risk of case or control samples. For example, in type 2 diabetes, odds ratios for established variants estimated from low–BMI cases are larger than those estimated from high–BMI cases. An unanswered question is how to use this information to maximize statistical power in case-control studies that ascertain individuals on the basis of phenotype (case-control ascertainment) or phenotype and clinical covariates (case-control-covariate ascertainment). While current approaches improve power in studies with random ascertainment, they often lose power under case-control ascertainment and fail to capture available power increases under case-control-covariate ascertainment. We show that an informed conditioning approach, based on the liability threshold model with parameters informed by external epidemiological information, fully accounts for disease prevalence and non-random ascertainment of phenotype as well as covariates and provides a substantial increase in power while maintaining a properly controlled false-positive rate. Our method outperforms standard case-control association tests with or without covariates...

‣ New statistical methods to assess the effect of time-dependent exposures in case-control studies

Cao, Zhirong
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
Português
Relevância na Pesquisa
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Contexte. Les études cas-témoins sont très fréquemment utilisées par les épidémiologistes pour évaluer l’impact de certaines expositions sur une maladie particulière. Ces expositions peuvent être représentées par plusieurs variables dépendant du temps, et de nouvelles méthodes sont nécessaires pour estimer de manière précise leurs effets. En effet, la régression logistique qui est la méthode conventionnelle pour analyser les données cas-témoins ne tient pas directement compte des changements de valeurs des covariables au cours du temps. Par opposition, les méthodes d’analyse des données de survie telles que le modèle de Cox à risques instantanés proportionnels peuvent directement incorporer des covariables dépendant du temps représentant les histoires individuelles d’exposition. Cependant, cela nécessite de manipuler les ensembles de sujets à risque avec précaution à cause du sur-échantillonnage des cas, en comparaison avec les témoins, dans les études cas-témoins. Comme montré dans une étude de simulation précédente, la définition optimale des ensembles de sujets à risque pour l’analyse des données cas-témoins reste encore à être élucidée, et à être étudiée dans le cas des variables dépendant du temps. Objectif: L’objectif général est de proposer et d’étudier de nouvelles versions du modèle de Cox pour estimer l’impact d’expositions variant dans le temps dans les études cas-témoins...

‣ Methylenetetrahydrofolate reductase gene variant (MTHFR C677T) and migraine: a case control study and meta-analysis

Samaan, Z.; Gaysina, D.; Cohen-Woods, S.; Craddock, N.; Jones, L.; Korszun, A.; Owen, M.; Mente, A.; McGuffin, P.; Farmer, A.
Fonte: BioMed Central Ltd. Publicador: BioMed Central Ltd.
Tipo: Artigo de Revista Científica
Publicado em //2011 Português
Relevância na Pesquisa
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Background: Migraine is a common disorder that often coexists with depression. While a functional polymorphism in methyleneterahydrofolate reductase gene (MTHFR C677T) has been implicated in depression; the evidence to support an association of MTHFR with migraine has been inconclusive. We aim to investigate the effect of this variant on propensity for migraine and to perform a systematic review and meta-analysis of studies of MTHFR and migraine to date. Methods: Individuals with migraine (n = 447) were selected from the Depression Case Control (DeCC) study to investigate the association between migraine and MTHFR C677T single nucleotide polymorphism (SNP) rs1801133 using an additive model compared to non-migraineurs adjusting for depression status. A meta-analysis was performed and included 15 studies of MTHFR and migraine. Results: MTHFR C677T polymorphism was associated with migraine with aura (MA) (OR 1.31, 95% CI 1.01-1.70, p = 0.039) that remained significant after adjusting for age, sex and depression status. A meta-analysis of 15 case-control studies showed that T allele homozygosity is significantly associated with MA (OR = 1.42; 95% CI, 1.10-1.82) and total migraine (OR = 1.37; 95% CI, 1.07-1.76), but not migraine without aura (OR = 1.16; 95% CI...

‣ Alcohol consumption and pancreatic cancer: a pooled analysis in the International Pancreatic Cancer Case-Control Consortium (PanC4)

Lucenteforte, E.; La Vecchia, C.; Silverman, D.; Petersen, G.M.; Bracci, P.M.; Ji, B.T.; Bosetti, C.; Li, D.; Gallinger, S.; Miller, A.B.; Bueno-de-Mesquita, H.B.; Talamini, R.; Polesel, J.; Ghadirian, P.; Baghurst, P.A.; Zatonski, W.; Fontham, E.; Bamlet
Fonte: Oxford University Press (OUP) Publicador: Oxford University Press (OUP)
Tipo: Artigo de Revista Científica
Publicado em //2012 Português
Relevância na Pesquisa
86.97342%
BACKGROUND: Heavy alcohol drinking has been related to pancreatic cancer, but the issue is still unsolved. METHODS: To evaluate the role of alcohol consumption in relation to pancreatic cancer, we conducted a pooled analysis of 10 case-control studies (5585 cases and 11,827 controls) participating in the International Pancreatic Cancer Case-Control Consortium. We computed pooled odds ratios (ORs) by estimating study-specific ORs adjusted for selected covariates and pooling them using random effects models. RESULTS: Compared with abstainers and occasional drinkers (< 1 drink per day), we observed no association for light-to-moderate alcohol consumption (≤ 4 drinks per day) and pancreatic cancer risk; however, associations were above unity for higher consumption levels (OR = 1.6, 95% confidence interval 1.2-2.2 for subjects drinking ≥ 9 drinks per day). Results did not change substantially when we evaluated associations by tobacco smoking status, or when we excluded participants who reported a history of pancreatitis, or participants whose data were based upon proxy responses. Further, no notable differences in pooled risk estimates emerged across strata of sex, age, race, study type, and study area. CONCLUSION: This collaborative-pooled analysis provides additional evidence for a positive association between heavy alcohol consumption and the risk of pancreatic cancer.; E. Lucenteforte...

‣ Ulcer, gastric surgery and pancreatic cancer risk: an analysis from the International Pancreatic Cancer Case-Control Consortium (PanC4)

Bosetti, C.; Lucenteforte, E.; Bracci, P.M.; Negri, E.; Neale, R.E.; Risch, H.A.; Olson, S.H.; Gallinger, S.; Miller, A.B.; Bueno-de-Mesquita, H.B.; Talamini, R.; Polesel, J.; Ghadirian, P.; Baghurst, P.A.; Zatonski, W.; Fontham, E.; Holly, E.A.; Gao, Y.T
Fonte: Oxford University Press (OUP) Publicador: Oxford University Press (OUP)
Tipo: Artigo de Revista Científica
Publicado em //2013 Português
Relevância na Pesquisa
86.97342%
BACKGROUND: Peptic ulcer and its treatments have been associated to pancreatic cancer risk, although the evidence is inconsistent. METHODS: We pooled 10 case-control studies within the Pancreatic Cancer Case-control Consortium (PanC4), including 4717 pancreatic cancer cases and 9374 controls, and estimated summary odds ratios (OR) using multivariable logistic regression models. RESULTS: The OR for pancreatic cancer was 1.10 [95% confidence interval (CI) 0.98-1.23] for history of ulcer (OR = 1.08 for gastric and 0.97 for duodenal ulcer). The association was stronger for a diagnosis within 2 years before cancer diagnosis (OR = 2.43 for peptic, 1.75 for gastric, and 1.98 for duodenal ulcer). The OR was 1.53 (95% CI 1.15-2.03) for history of gastrectomy; however, the excess risk was limited to a gastrectomy within 2 years before cancer diagnosis (OR = 6.18, 95% CI 1.82-20.96), while no significant increased risk was observed for longer time since gastrectomy. No associations were observed for pharmacological treatments for ulcer, such as antacids, H2-receptor antagonists, or proton-pump inhibitors. CONCLUSIONS: This uniquely large collaborative study does not support the hypothesis that peptic ulcer and its treatment materially affect pancreatic cancer risk. The increased risk for short-term history of ulcer and gastrectomy suggests that any such association is due to increased cancer surveillance.; C. Bosetti...

‣ The effect of misclassification error on risk estimation in case-control studies

Baena,Armando; Garcés-Palacio,Isabel Cristina; Grisales,Hugo
Fonte: Associação Brasileira de Saúde Coletiva Publicador: Associação Brasileira de Saúde Coletiva
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2015 Português
Relevância na Pesquisa
86.94752%
INTRODUCTION: In epidemiological studies, misclassification error, especially differential misclassification, has serious implications. OBJECTIVE: To illustrate how differential misclassification error (DME) and non-differential misclassification error (NDME) occur in a case-control design and to describe the trends in DME and NDME. METHODS: Different sensitivity levels, specificity levels, prevalence rates and odds ratios were simulated. Interaction graphics were constructed to study bias in the different settings, and the effect of the different factors on bias was described using linear models. RESULTS: One hundred per cent of the biases caused by NDME were negative. DME biased the association positively more often than it did negatively (70 versus 30%), increasing or decreasing the OR estimate towards the null hypothesis. CONCLUSIONS: The effect of the sensitivity and specificity in classifying exposure, the prevalence of exposure in controls and true OR differed between positive and negative biases. The use of valid exposure classification instruments with high sensitivity and high specificity is recommended to mitigate this type of bias.

‣ Early estimates of seasonal influenza vaccine effectiveness in Europe among target groups for vaccination: results from the I-MOVE multicentre case-control study, 2011/12

Kissling, E.; Valenciano, M.; I-MOVE, Case-Control Studies Team
Fonte: ECDC_European Centre for Disease Prevention and Control Publicador: ECDC_European Centre for Disease Prevention and Control
Tipo: Artigo de Revista Científica
Publicado em 12/04/2012 Português
Relevância na Pesquisa
86.77566%
Colaboração de: Baltazar Nunes, investigador do DEP; To provide an early estimate of 2011/12 influenza vaccine effectiveness (VE), we conducted a multicentre case–control study based on seven sentinel surveillance networks. We included influenza-like illness cases up to week 7/2012 from the vaccination target groups, swabbed less than eight days after symptom onset. Laboratory-confirmed influenza A(H3) cases were compared to negative controls. Adjusted VE was 43% (95% confidence interval: -0.4 to 67.7), suggesting low to moderate VE against influenza A(H3) in the early 2011/12 season.

‣ Potential role of the lectin pathway of complement in the pathogenesis and disease manifestations of systemic sclerosis: a case-control and cohort study

Osthoff, M.; Ngian, G.S.; Dean, M.M.; Nikpour, M.; Stevens, W.; Proudman, S.; Eisen, D.P.; Sahhar, J.
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
Publicado em //2014 Português
Relevância na Pesquisa
77.050127%
INTRODUCTION: Repetitive episodes of ischemia and reperfusion (I/R) are a cardinal feature of the pathogenesis of systemic sclerosis (SSc), which precedes tissue fibrosis. The complement system is a key mediator of tissue damage after I/R, primarily by activation of the lectin pathway. This study investigated whether serum levels and polymorphisms of mannose-binding lectin (MBL) and ficolin-2 (FCN2), two pattern recognition receptors of the lectin pathway, are associated with the predisposition to and clinical features of SSc. METHODS: A case-control study was undertaken involving 90 patients with SSc from a single SSc outpatient clinic and 90 age- and sex-matched blood donors. MBL and FCN2 levels and polymorphisms were measured in both groups, and in cases correlated with clinical data. RESULTS: MBL levels and genotypes were equally distributed in cases and controls while there were some significant differences in FCN2 polymorphisms. Median MBL levels were higher in SSc cases with diffuse disease compared with controls (2.6 versus 1.0 μg/ml, P <0.001). CONCLUSIONS: Overall, predisposition to SSc was not influenced by the lectin pathway of complement in our matched case-control study. However, our preliminary data suggest that MBL...

‣ An outbreak of Legionnaires disease at the Melbourne Aquarium, April 2000: investigation and case-control studies

Greig, Jane E; Carnie, John A; Tallis, G M; Ryan, Norbert J; Tan, Agnes; Gordon, Ian R; Zwolak, Bernard; Leydon, Jennie A; Guest, Charles; Hart, William G
Fonte: Australasian Medical Association Publicador: Australasian Medical Association
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
87.03326%
Objective: To investigate the source and risk factors associated with Australia's largest outbreak of Legionnaires' disease. Design and setting: Epidemiological and environmental investigation of cases of Legionnaires' disease associated with visits to the Melbourne Aquarium; two case-control studies to confirm the outbreak source and to investigate risk factors for infection, respectively Participants: Patients with confirmed Legionnaires' disease who visited the Melbourne Aquarium between 11 and 27 April 2000 were compared (i) with control participants from the community, and (ii) with control participants selected from other visitors to the Aquarium during this period. Main outcome measures: Risk factors for acquiring Legionnaires' disease. Results: There were 125 confirmed cases of Legionnaires' disease caused by Legionella pneumophila serogroup 1 associated with the Aquarium; 76% of patients were hospitalised, and four (3.2%) died. The Aquarium cooling towers were contaminated with this organism. Visiting the Aquarium was significantly associated with disease (odds ratio [OR], 207; 95% Cl, 73-630). The case-control study indicated that current smoking was a dose-dependent risk (multivariable OR for currently smoking > 70 cigarettes/week...

‣ Utilização de estratificação e modelo de regressão logística na análise de dados de estudos caso-controle; Using of stratification and the logistic regression model in the analysis of data of case-control studies

Gimeno, Suely Godoy Agostinho; Souza, José Maria Pacheco de
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 01/08/1995 Português
Relevância na Pesquisa
86.87081%
Exemplifica-se a aplicação de análise multivariada, por estratificação e com regressão logística, utilizando dados de um estudo caso-controle sobre câncer de esôfago. Oitenta e cinco casos e 292 controles foram classificados segundo sexo, idade e os hábitos de beber e de fumar. As estimativas por ponto dos odds ratios foram semelhantes, sendo as duas técnicas consideradas complementares.; Data of a case-control study of esophageal cancer were used as an example of the use of multivariate analysis with stratification and logistic regression. Eighty-five cases and 292 controls were classified according to sex, age and smoking and drinking habits. The point estimates of the odds ratios were similar, and the techniques were considered complementary.

‣ Retreatment in leprosy: a case-control study

Ximenes,Ricardo Arraes Alencar; Gallo,Maria Eugênia Novinsk; Brito,Maria de Fátima de Medeiros
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 01/08/2007 Português
Relevância na Pesquisa
77.008164%
OBJECTIVE: To assess risk factors for retreatment of leprosy patients. METHODS: A case-control study with patients from two reference care units in Recife, northeastern Brazil, in 2003. The case group included retreated patients (N=155) and the control group comprised those patients who were not retreated (N=155) matched by year of diagnosis and health care unit. Univariate and multivariate analyses were conducted to test the associations and odds ratios and related 95% confidence intervals were estimated. RESULTS: The following factors were found to be significantly associated (p<0.05) with retreatment: occurrence of adverse immunological reactions after treatment completion (OR=2.3; 95% CI=1.18;4.83), final bacterial index > 1 (OR=6.43; 95% CI=1.67;24.74), therapeutic regimen consisting of sulfone monotherapy (OR=10; 95% CI=0.01;0.78) and reports of household contacts (OR=2.2; 95% CI=0.24;0.85). CONCLUSIONS: The study findings reinforce that the use of dapsone monotherapy should be discontinued, and highlight the need for epidemiological monitoring of specific groups of leprosy patients after treatment completion through periodical clinical and laboratory evaluation. Further studies to explore the association between final bacterial index and retreatment are strongly recommended.

‣ Hospital visitors as controls in case-control studies

Mendonça,Gulnar Azevedo S; Eluf-Neto,José
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 01/10/2001 Português
Relevância na Pesquisa
97.08487%
OBJECTIVE: Selecting controls is one of the most difficult tasks in the design of case-control studies. Hospital controls may be inadequate and random controls drawn from the base population may be unavailable. The aim was to assess the use of hospital visitors as controls in a case-control study on the association of organochlorinated compounds and other risk factors for breast cancer conducted in the main hospital of the "Instituto Nacional de Câncer" -- INCA (National Cancer Institute) in Rio de Janeiro (Brazil). METHODS: The study included 177 incident cases and 377 controls recruited among female visitors. Three different models of control group composition were compared: Model 1, with all selected visitors; Model 2, excluding women visiting relatives with breast cancer; and Model 3, excluding all women visiting relatives with any type of cancer. Odds ratios (OR) and 95% confidence intervals were calculated to test the associations. RESULTS: Age-adjusted OR for breast cancer associated with risk factors other than family history of cancer, except smoking and breast size, were similar in the three models. Regarding family history of all cancers, except for breast cancer, there was a decreased risk in Models 1 and 2, while in Model 3 there was an increased risk...

‣ Nested case-control study in a serological survey to evaluate the effectiveness of a Chagas disease control programme in Brazil

Carneiro,M.; Moreno,E.C.; Antunes,C.M.F.
Fonte: World Health Organization Publicador: World Health Organization
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2001 Português
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OBJECTIVE: To identify risk factors associated with Trypanosoma cruzi infections in areas under surveillance in the State of Minas Gerais, Brazil. METHODS:A model using a nested case-control design incorporated within a serological survey of schoolchildren which was employed to evaluate the effectiveness of the Chagas disease control programme. FINDINGS:In a sample of 40 374 schoolchildren (aged 7-14 years) surveyed, 16 children tested positive for T. cruzi antibody (by indirect immunofluorescence and indirect haemagglutination). In the case-control study, each case was randomly matched to three seronegative controls (classroom and age + 1 year). Compared to controls, T. cruzi-seropositive children were more likely to have a seropositive mother (odds ratio (OR) = 6.8; 95% confidence interval (CI) = 0.71-63.9) or a seropositive family member (OR = 8.6; 95% CI = 1.0-75.5). CONCLUSION:Use of the nested case-control model in a sero-epidemiological survey to evaluate risk factors for T. cruzi transmission was adequate for assessing the effectiveness of a Chagas disease control programme.