984 resultados para Epidemiologic study


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Previously developed models for predicting absolute risk of invasive epithelial ovarian cancer have included a limited number of risk factors and have had low discriminatory power (area under the receiver operating characteristic curve (AUC) < 0.60). Because of this, we developed and internally validated a relative risk prediction model that incorporates 17 established epidemiologic risk factors and 17 genome-wide significant single nucleotide polymorphisms (SNPs) using data from 11 case-control studies in the United States (5,793 cases; 9,512 controls) from the Ovarian Cancer Association Consortium (data accrued from 1992 to 2010). We developed a hierarchical logistic regression model for predicting case-control status that included imputation of missing data. We randomly divided the data into an 80% training sample and used the remaining 20% for model evaluation. The AUC for the full model was 0.664. A reduced model without SNPs performed similarly (AUC = 0.649). Both models performed better than a baseline model that included age and study site only (AUC = 0.563). The best predictive power was obtained in the full model among women younger than 50 years of age (AUC = 0.714); however, the addition of SNPs increased the AUC the most for women older than 50 years of age (AUC = 0.638 vs. 0.616). Adapting this improved model to estimate absolute risk and evaluating it in prospective data sets is warranted.

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A Depressão na infância e adolescência, tal como na população adulta, é uma das perturbações mentais mais comuns. Uma vez que o seu aparecimento nestas faixas etárias conduz a graves consequências na idade adulta, é fundamental identificar os sintomas depressivos precocemente. Desta forma, os instrumentos de autorrelato têm um papel fundamental, uma vez que permitem com facilidade, de forma fidedigna e válida, ter acesso a formas de pensar, sentir e agir dos sujeitos. O objetivo do presente trabalho consistiu na tradução, adaptação e estudo da Center for Epidemiological Studies Depression Scale for Children (CES-DC) (Weissman, Orvash & Padian, 1980) para os adolescentes portugueses. A amostra é constituída por 417 adolescentes, com idades compreendidas entre os 12 e os 18 anos a frequentar o 3º ciclo do ensino básio e ensino secundário. Para o estudo da validade convergente e divergente da CES-DC, foram utilizados a Depression Anxiety Stress Scales (DASS 21) (Lovibond & Lovibond, 1995), o Children's Depresssion Inventory (CID) (Marujo, 1994) e a Students' Life Satisfaction Scale (SLSS) (Marques, Pais-Ribeiro & Lopez, 2007) que avaliam, respetivamente, os estados emocionais negativos (depressão, ansiedade e stress), a sintomatologia depressiva e a satisfação global com a vida. Os resultados obtidos mostram que a escala possui uma boa consistência interna, uma estabilidade temporal adequada, assim como uma boa validade. Sugerem, ainda, tratar-se de uma escala tridimensional: fator humor, fator interpessoal e fator felicidade. Estes dados permitem o avanço da Psicologia, no que diz respeito à avaliação e prática clínica com adolescentes. A utilidade do questionário deve ser verificada noutras faixas etárias, principalmente, nas de menos de 12 anos de idade, e também numa amostra clínica. Não obstante as limitações apontadas, os resultados sugerem que a CES-DC é um questionário útil na avaliação de sintomas depressivos nos adolescentes. / Depression in children and adolescents, as well as in adults, is one of the most common mental disorders. Since its appearance in these age groups leads to serious consequences in adulthood, it is critical to identify depressive symptoms in early stages. Therefore, self-report instruments play a key role in this contexto since they allow to easily, reliably and validly have access to ways the subject thinks, feels and acts. The aim of this study was to translate, adapt and study the Center for Epidemiological Studies Depression Scale for Children (CES-DC) (Weissman, Orvash & Padian, 1980) for portuguese adolescents. The sample consists of 417 adolescents, aged between 12 and 18 years old, attending the 3rd cycle of basic education and secondary education schools. To study the convergent and divergent validity of the CES-DC, the Depression Anxiety Stress Scales (DASS 21) (Lovibond & Lovibond, 1995) was used, along with the Children's depression Inventory (CDI) (Sailor, 1994) and the Students' Life Satisfaction Scale (SLSS) (Marques, Pais-Ribeiro & Lopez, 2007) that evaluate, respectively, the negative emotional states (depression, anxiety and stress), depressive symptoms and overall satisfaction with life. The results show that the evaluated scale presents a good internal consistency, an adequate temporal stability as well as good validity. They also suggest that this is a three-dimensional scale: humor factor, interpersonal factor and happiness factor. These data allow for the progress of psychology, regarding the assessment and clinical practice among adolescents. The usefulness of the questionnaire should be verified in other age groups, especially in children with less than 12 years old and in a clinical sample. Despite these limitations, the results suggest that CES-DC is useful in the assessment questionnaire of depressive symptoms in adolescents.

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Objectives: To determine the frequency of vaccination in older adults within the city of Bogotá and to estimate the association with sociodemographic and health factors. Methods: This is a secondary data analysis from the SABE-Bogotá Study, a cross-sectional population-based study that included a total of 2,000 persons aged 60 years. Weighted percentages for self-reported vaccination [influenza, pneumococcal, tetanus] were determined. The association between vaccination and covariates was evaluate by logistic regression models. Results: A total of 73.0% of respondents received influenza, 57.8% pneumococcal and 47.6% tetanus vaccine. Factors independently associated with vaccination included: 1- age (65-74 years had higher odds of receiving vaccinations, compared to 60-64 years; 2- socioeconomic status (SES) (higher SES had lower odds of having influenza and pneumococcal vaccines, compared to those with lower SES); 3- health insurance (those with contributive or subsidized health insurance had higher odds (between 3 and 5 times higher) of having vaccinations, compared to those with no insurance); 4- older adults with better functional status (greater Lawton scores) had increased odds for all vaccinations; 5- older adults with higher comorbidity had increased odds for influenza and pneumococcal vaccinations. Conclusion: Vaccination campaigns should be strengthened to increase vaccination coverage, especially in the group more reticent to vaccination or vulnerable to reach it such as the disable elder.

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Objectifs: Examiner les tendances temporelles, les déterminants en lien avec le design des études et la qualité des taux de réponse rapportés dans des études cas-témoins sur le cancer publiées lors des 30 dernières années. Méthodes: Une revue des études cas-témoins sur le cancer a été menée. Les critères d'inclusion étaient la publication (i) dans l’un de 15 grands périodiques ciblés et (ii) lors de quatre périodes de publication (1984-1986, 1995, 2005 et 2013) couvrant trois décennies. 370 études ont été sélectionnées et examinées. La méthodologie en lien avec le recrutement des sujets et la collecte de données, les caractéristiques de la population, les taux de participation et les raisons de la non-participation ont été extraites de ces études. Des statistiques descriptives ont été utilisées pour résumer la qualité des taux de réponse rapportés (en fonction de la quantité d’information disponible), les tendances temporelles et les déterminants des taux de réponse; des modèles de régression linéaire ont été utilisés pour analyser les tendances temporelles et les déterminants des taux de participation. Résultats: Dans l'ensemble, les qualités des taux de réponse rapportés et des raisons de non-participation étaient très faible, particulièrement chez les témoins. La participation a diminué au cours des 30 dernières années, et cette baisse est plus marquée dans les études menées après 2000. Lorsque l'on compare les taux de réponse dans les études récentes a ceux des études menées au cours de 1971 à 1980, il y a une plus grande baisse chez les témoins sélectionnés en population générale ( -17,04%, IC 95%: -23,17%, -10,91%) que chez les cas (-5,99%, IC 95%: -11,50%, -0,48%). Les déterminants statistiquement significatifs du taux de réponse chez les cas étaient: le type de cancer examiné, la localisation géographique de la population de l'étude, et le mode de collecte des données. Le seul déterminant statistiquement significatif du taux de réponse chez les témoins hospitaliers était leur localisation géographique. Le seul déterminant statistiquement significatif du taux de participation chez les témoins sélectionnés en population générale était le type de répondant (sujet uniquement ou accompagné d’une tierce personne). Conclusion: Le taux de participation dans les études cas-témoins sur le cancer semble avoir diminué au cours des 30 dernières années et cette baisse serait plus marquée dans les études récentes. Afin d'évaluer le niveau réel de non-participation et ses déterminants, ainsi que l'impact de la non-participation sur la validité des études, il est nécessaire que les études publiées utilisent une approche normalisée pour calculer leurs taux de participation et qu’elles rapportent ceux-ci de façon transparente.

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Objectifs: Examiner les tendances temporelles, les déterminants en lien avec le design des études et la qualité des taux de réponse rapportés dans des études cas-témoins sur le cancer publiées lors des 30 dernières années. Méthodes: Une revue des études cas-témoins sur le cancer a été menée. Les critères d'inclusion étaient la publication (i) dans l’un de 15 grands périodiques ciblés et (ii) lors de quatre périodes de publication (1984-1986, 1995, 2005 et 2013) couvrant trois décennies. 370 études ont été sélectionnées et examinées. La méthodologie en lien avec le recrutement des sujets et la collecte de données, les caractéristiques de la population, les taux de participation et les raisons de la non-participation ont été extraites de ces études. Des statistiques descriptives ont été utilisées pour résumer la qualité des taux de réponse rapportés (en fonction de la quantité d’information disponible), les tendances temporelles et les déterminants des taux de réponse; des modèles de régression linéaire ont été utilisés pour analyser les tendances temporelles et les déterminants des taux de participation. Résultats: Dans l'ensemble, les qualités des taux de réponse rapportés et des raisons de non-participation étaient très faible, particulièrement chez les témoins. La participation a diminué au cours des 30 dernières années, et cette baisse est plus marquée dans les études menées après 2000. Lorsque l'on compare les taux de réponse dans les études récentes a ceux des études menées au cours de 1971 à 1980, il y a une plus grande baisse chez les témoins sélectionnés en population générale ( -17,04%, IC 95%: -23,17%, -10,91%) que chez les cas (-5,99%, IC 95%: -11,50%, -0,48%). Les déterminants statistiquement significatifs du taux de réponse chez les cas étaient: le type de cancer examiné, la localisation géographique de la population de l'étude, et le mode de collecte des données. Le seul déterminant statistiquement significatif du taux de réponse chez les témoins hospitaliers était leur localisation géographique. Le seul déterminant statistiquement significatif du taux de participation chez les témoins sélectionnés en population générale était le type de répondant (sujet uniquement ou accompagné d’une tierce personne). Conclusion: Le taux de participation dans les études cas-témoins sur le cancer semble avoir diminué au cours des 30 dernières années et cette baisse serait plus marquée dans les études récentes. Afin d'évaluer le niveau réel de non-participation et ses déterminants, ainsi que l'impact de la non-participation sur la validité des études, il est nécessaire que les études publiées utilisent une approche normalisée pour calculer leurs taux de participation et qu’elles rapportent ceux-ci de façon transparente.

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The prevalence of morbid obesity has been shown to be increasing at an even greater rate than general obesity in many developed countries and is likely to continue to ncrease. The high risks of a range of chronic diseases associated with morbid obesity make this a critical ealthcare challenge. Although comprehensive epidemiologic data are not yet available for all the health risks associated with morbid obesity, it is likely to be associated with very high risks of diseases with a large impact on the individual and the health system, including diabetes, cardiovascular disease, sleep apnea, cancer, osteoarthritis, infertility, depression, and mortality.

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The thermal decomposition of natural ammonium oxalate known as oxammite has been studied using a combination of high resolution thermogravimetry coupled to an evolved gas mass spectrometer and Raman spectroscopy coupled to a thermal stage. Three mass loss steps were found at 57, 175 and 188°C attributed to dehydration, ammonia evolution and carbon dioxide evolution respectively. Raman spectroscopy shows two bands at 3235 and 3030 cm-1 attributed to the OH stretching vibrations and three bands at 2995, 2900 and 2879 cm-1, attributed to the NH vibrational modes. The thermal degradation of oxammite may be followed by the loss of intensity of these bands. No intensity remains in the OH stretching bands at 100°C and the NH stretching bands show no intensity at 200°C. Multiple CO symmetric stretching bands are observed at 1473, 1454, 1447 and 1431cm-1, suggesting that the mineral oxammite is composed of a mixture of chemicals including ammonium oxalate dihydrate, ammonium oxalate monohydrate and anhydrous ammonium oxalate.

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The tridecameric Al-polymer [AlO4Al12(OH)24(H2O)12]7+ was prepared by forced hydrolysis of Al3+ up to an OH/Al molar ratio of 2.2. Under slow evaporation crystals were formed of Al13-nitrate. Upon addition of sulfate the tridecamer crystallised as the monoclinic Al13-sulfate. These crystals have been studied using near-infrared spectroscopy and compared to Al2(SO4)3.16H2O. Although the near-infrared spectra of the Al13-sulfate and nitrate are very similar indicating similar crystal structures, there are minor differences related to the strength with which the crystal water molecules are bonded to the salt groups. The interaction between crystal water and nitrate is stronger than with the sulfate as reflected by the shift of the crystal water band positions from 6213, 4874 and 4553 cm–1 for the Al13 sulfate towards 5925, 4848 and 4532 cm–1 for the nitrate. A reversed shift from 5079 and 5037 cm–1 for the sulfate towards 5238 and 5040 cm–1 for the nitrate for the water molecules in the Al13 indicate that the nitrate-Al13 bond is weakened due to the influence of the crystal water on the nitrate. The Al-OH bond in the Al13 complex is not influenced by changing the salt group due to the shielding by the water molecules of the Al13 complex.