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Concordância de medidas antropométricas em estudo epidemiológico de base populacional: Ribeirão Preto, SP, 2006. Projeto OBEDIARP; Agreement of anthropometric measures in a population-based epidemiological study: Ribeirão Preto, SP, 2006. OBEDIARP Project

CASTRO, Vanilde de; MORAES, Suzana Alves de; FREITAS, Isabel Cristina Martins de
Fonte: Associação Brasileira de Pós -Graduação em Saúde Coletiva Publicador: Associação Brasileira de Pós -Graduação em Saúde Coletiva
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
35.85%
O objetivo do estudo foi avaliar o acordo de medidas antropométricas aferidas e referidas de peso e altura em 632 adultos. O acordo foi calculado por meio do coeficiente de correlação intraclasse, obtido por análise de variância com 01 critério de classificação, e pelas diferenças médias e limites de acordo, segundo Bland e Altman. O acordo intracategorias do estado nutricional foi avaliado pela estatística kappa. No sexo masculino, os CCIs foram 0,926 (IC95%: 0,894-0,959) e 0,873 (IC95%: 0,799-0,946), para medidas de peso e altura, respectivamente, sendo a diferença média e os limites de acordo para o IMC de 0,143kg/m² (-2,844-3,129). No sexo feminino, os respectivos CCIs foram 0,981 (IC95%: 0,973-0,988) e 0,794 (IC95%: 0,687-0,900), sendo a diferença e os limites de acordo para o IMC de 0,462kg/m² (-2,457-3,382). Os coeficientes kappa para o estado nutricional, no sexo masculino e feminino, foram, respectivamente, 0,777 (IC95%: 0,683-0,872) e 0,793(IC95%: 0,725-0,862). As medidas referidas são alternativas apropriadas para a classificação do estado nutricional em estudos epidemiológicos.; This study aimed to assess the agreement between measured and self-reported height and weight measures in 632 adults. The agreement was calculated using an intra-class correlation coefficient (estimated by ANOVA using one classification criterion)...

Identification of dietary patterns using factor analysis in an epidemiological study in São Paulo

Marchioni,Dirce Maria Lobo; Latorre,Maria do Rosário Dias de Oliveira; Eluf-Neto,José; Wünsch-Filho,Victor; Fisberg,Regina Mara
Fonte: Associação Paulista de Medicina - APM Publicador: Associação Paulista de Medicina - APM
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/05/2005 EN
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36.08%
CONTEXT AND OBJECTIVE: Diet and nutrition are environmental factors in health/disease relationships. From the epidemiological viewpoint, diet represents a complex set of highly correlated exposures. Our objective was to identify patterns of food intake in a group of individuals living in São Paulo, and to develop objective dietary measurements for epidemiological purposes. DESIGN AND LOCAL: Exploratory factor analysis of data in a case-control study in seven teaching hospitals in São Paulo. METHODS: The participants were 517 patients (260 oral cancer cases and 257 controls) admitted to the study hospitals between November 1998 and March 2001. The weekly intake frequencies for dairy products, cereals, meat, processed meat, vegetables, pulses, fruits and sweets were assessed by means of a semi-quantitative food frequency questionnaire. Dietary patterns were identified by factor analysis, based on the intake of the eight food groups, using principal component analysis as an extraction method followed by varimax rotation. RESULTS: Factor analysis identified three patterns that accounted for 55% of the total variability within the sample. The first pattern ("prudent") was characterized by vegetable, fruit and meat intake; the second ("traditional") by cereals (mainly rice) and pulses (mainly beans); and the third ("snacks") by dairy products and processed meat. CONCLUSION: This study identified food intake patterns through an a posteriori approach. Such analysis may be useful for nutritional intervention programs and...

Biochemical fingerprinting compared with ribotyping and pulsed-field gel electrophoresis of DNA for epidemiological typing of enterococci.

Kühn, I; Burman, L G; Haeggman, S; Tullus, K; Murray, B E
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /11/1995 EN
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25.93%
The Phene Plate (PhP) biochemical fingerprinting system for bacteria is based on measurements of the kinetics of bacterial biochemical reactions. This system was modified for typing of enterococci and was compared with DNA typing by pulsed-field gel electrophoresis and with ribotyping by using 45 Enterococcus faecalis isolates from international collections. It was also used to study 170 fecal enterococcal isolates from healthy individuals and 28 isolates of E. faecalis from the blood of neonates. The PhP system showed a high degree of discriminatory power for unrelated enterococcal isolates. Among the 170 unrelated fecal isolates, 107 isolates from international collections, PhP typing discriminated 19 types, and ribotyping discriminated 5 types. In most cases, when isolates were of the same DNA type, they were also of the same PhP type, and the level of agreement between these two methods was high (96%). A combination of PhP typing and DNA typing identified 34 different types, but ribotyping did not yield any further discrimination. PhP typing of E. faecalis isolates from healthy individuals (n = 89) and from the blood of neonates with septicemia (n = 28) yielded a diversity of 0.93 for both populations and similar major PhP types in both populations. Thus...

Analysis of bronchial reactivity in epidemiological studies.

Abramson, M J; Saunders, N A; Hensley, M J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /12/1990 EN
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25.98%
The measurement of bronchial reactivity in epidemiological studies has the advantage of quantifying an objective physiological feature of asthma. Bronchial reactivity was developed in a clinical setting and has been conventionally expressed as the dose of agonist producing a 20% fall in FEV1 (PD20). As PD20 can be estimated for less than 20% of subjects in general community surveys with the doses of agonist that are usually given, data from most subjects must be censored. Thus PD20 alone is a poor index of bronchial reactivity for epidemiological studies. Data from 809 aluminium smelter workers were used to evaluate alternative methods of analysing bronchial reactivity. Dose-response relationships were analysed by four methods: (1) PD20 by the conventional method of interpolating the dose on a logarithmic scale between the last two measurements of FEV1; (2) PD20 (with allowance for extrapolation), estimated by fitting an exponential curve to the dose-response data; (3) the linear regression slope between dose and FEV1 when significant; (4) the dose-response slope obtained in all subjects as the % change in FEV1 from baseline in response to total dose. When each of these measures was related to symptoms, diagnosis, and treatment of asthma...

Definition of osteoarthritis of the knee for epidemiological studies.

Spector, T D; Hart, D J; Byrne, J; Harris, P A; Dacre, J E; Doyle, D V
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /11/1993 EN
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25.95%
OBJECTIVES--There are no agreed criteria for osteoarthritis (OA) of the knee in population studies. The radiographic scoring system of Kellgren and Lawrence has been the system most used in the past and although other methods have been developed, comparisons have not been performed. Therefore these grading systems were compared in radiographs from a general population sample. METHODS--Anteroposterior weightbearing radiographs of 1954 knees from 977 women aged 45-64 years from the Chingford population study were read by a variety of methods, including quantitative measures of minimum joint space, qualitative measures of osteophytes and of joint space, and a qualitative Kellgren and Lawrence global score. All qualitative methods used standardised atlases. Intra-observer and interobserver reproducibility was tested on a subgroup of 100 films using three observers and two readings. Variables were dichotomised at the tenth and second centiles to define OA. Odds ratios were calculated for each method for the association of OA with knee pain, obesity, and with each of the other methods. RESULTS--Most methods had high intraobserver and interobserver reproducibility, except for measurements of lateral joint space. The best predictors of knee pain were the presence of osteophytes and the Kellgren and Lawrence grade. Methods measuring narrowing performed less well...

Use of routinely collected data on trihalomethane in drinking water for epidemiological purposes

Keegan, T; Whitaker, H; Nieuwenhuijsen, M; Toledano, M; Elliott, P; Fawell, J; Wilkinson, M; Best, N
Fonte: BMJ Group Publicador: BMJ Group
Tipo: Artigo de Revista Científica
Publicado em /07/2001 EN
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25.93%
OBJECTIVES—To explore the use of routinely collected trihalomethane (THM) measurements for epidemiological studies. Recently there has been interest in the relation between byproducts of disinfection of public drinking water and certain adverse reproductive outcomes, including stillbirth, congenital malformations, and low birth weight.
METHOD—Five years of THM readings (1992-6), collected for compliance with statutory limits, were analysed. One water company in the north west of England, divided into 288 water zones, provided 15 984 observations for statistical analysis. On average each zone was sampled 11.1 times a year. Five year, annual, monthly, and seasonal variation in THMs were examined as well as the variability within and between zones.
RESULTS—Between 1992 and 1996 the total THM (TTHM) annual zone means were less than half the statutory concentration, at approximately 46 µg/l. Differences in annual water zone means were within 7%. Over the study period, the maximum water zone mean fell from 142.2 to 88.1 µg/l. Mean annual concentrations for individual THMs (µg/l) were 36.6, 8.0, and 2.8 for chloroform, bromodichloromethane (BDCM), and dibromochloromethane (DBCM) respectively. Bromoform data were not analysed...

Effect of spirometer temperature on FEV1 in a longitudinal epidemiological study

Gilliland, F. D.; Linn, W.; Rappaport, E.; Avol, E.; Gong, H.; Peters, J.
Fonte: BMJ Group Publicador: BMJ Group
Tipo: Artigo de Revista Científica
Publicado em /10/1999 EN
Relevância na Pesquisa
26.03%
OBJECTIVES: To assess the magnitude of error in pulmonary function measurements introduced by variation in spirometer temperature under field conditions. In a large scale epidemiological study of school children, the influence was investigated of spirometer temperature on forced expiratory volume in 1 second (FEV1) measured with dry rolling seal volumetric spirometers and conventional body temperature, pressure, and saturation (BTPS) corrections. METHODS: Linear regression analyses were performed on data from 995 test-retest pairs on 851 different children, with 1-110 days between test and retest, and spirometer temperature differences between -13 degrees C and +9 degrees C. RESULTS: After adjusting for effects of growth (test-retest intervals) and circadian variation (changes in times of testing), differences in standard BTPS corrected FEV1 showed significant (p < 0.05) dependence on differences in spirometer temperature between tests (-0.24%/degree C). CONCLUSIONS: When spirometer temperatures vary widely, standard BTPS correction does not fully adjust for gas contraction. To improve accuracy of volume measurements in epidemiological studies, additional correction for variation in spirometer temperature should be considered.

The effectiveness of HIV prevention and the epidemiological context.

Grassly, N. C.; Garnett, G. P.; Schwartländer, B.; Gregson, S.; Anderson, R. M.
Fonte: World Health Organization Publicador: World Health Organization
Tipo: Artigo de Revista Científica
Publicado em //2001 EN
Relevância na Pesquisa
26.03%
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.

Improving cost-effectiveness of epidemiological studies via designed missingness strategies

Strauss, Warren; Ryan, Louise; Morara, Michele; Iroz-Elardo, Nicole; Davis, Mark; Cupp, Matt; Nishioka, Marcia; Quackenboss, James; Galke, Warren; Özkaynak, Haluk; Scheidt, Peter
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/06/2010 EN
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25.93%
Modern epidemiological studies face opportunities and challenges posed by an ever-expanding capacity to measure a wide range of environmental exposures, along with sophisticated biomarkers of exposure and response at the individual level. The challenge of deciding what to measure is further complicated for longitudinal studies, where logistical and cost constraints preclude the collection of all possible measurements on all participants at every follow-up time. This is true for the National Children’s Study (NCS), a large scale longitudinal study that will enroll children starting in early pregnancy and gather information on their development and environment through early adulthood. The success of the NCS will significantly depend on the accurate, yet cost-effective, characterization of environmental exposures thought to be related to the health outcomes of interest. The purpose of this paper is to explore the use of cost saving, yet valid and adequately powered statistical approaches for gathering exposure information within epidemiological cohort studies. The proposed approach involves the collection of detailed exposure assessment information on a specially selected subset of the study population, and collection of less-costly...

Temporal reproducibility of taurine measurements in frozen serum of healthy postmenopausal women

Wójcik, Oktawia P.; Koenig, Karen L.; Zeleniuch-Jacquotte, Anne; Costa, Max; Chen, Yu
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
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26.01%
Animal studies and small clinical trials have shown that taurine (2-aminoethanesulphonic acid), a sulphur-containing molecule mainly obtained from the diet in human subjects, has a variety of biological actions that are related to atherosclerosis and cardiovascular functions. However, epidemiological studies of taurine and CHD risk are lacking. We evaluated whether a single measurement of serum taurine could serve as an estimate for long-term serum levels. Serum taurine was measured using HPLC in three annual samples from thirty postmenopausal women selected from the New York University Women’s Health Study. Overall, serum taurine values ranged from 62·8 to 245·3 nmol/ml, with a mean of 140 nmol/ml. The intraclass correlation coefficient of a single measurement of serum taurine was 0·48 (95 % CI 0·26, 0·68), which can be improved to 0·65 by using the mean of two annual measurements. The CV was 7 %. These results indicate that the mean of two or more annual measurements of serum taurine is a sufficiently reliable measure of long-term serum levels that can be used in epidemiological studies.

Measurements of light at night (LAN) for a sample of female school teachers

Rea, Mark S.; Brons, Jennifer A.; Figueiro, Mariana G.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
25.91%
Epidemiological studies have shown an association between rotating shiftwork and breast cancer (BC) risk. Recently, light at night (LAN) measured by satellite photometry and by self-reports of bedroom brightness has been shown to be associated with BC risk, irrespective of shiftwork history. Importance has been placed on these associations because retinal light exposures at night can suppress the hormone melatonin and/or disrupt circadian entrainment to the local 24-h light-dark cycle. The present study examined whether it was valid to use satellite photometry and self-reports of brightness to characterize light, as it might stimulate the circadian system and thereby affect BC incidence. Calibrated photometric measurements were made at the bedroom windows and in the bedrooms of a sample of female school teachers, who worked regular dayshifts and lived in a variety of satellite-measured sky brightness categories. The light levels at both locations were usually very low and were independent of the amount of satellite-measured light. Calibrated photometric measurements were also obtained at the corneas of these female school teachers together with calibrated accelerometer measurements for seven consecutive days and evenings. Based upon these personal light exposure and activity measurements...

The potential of Pathfinder AVHRR data for providing surrogate climatic variables across Africa and Europe for epidemiological applications

Green, Robert M.; Hay, Simon I.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /02/2002 EN
Relevância na Pesquisa
25.95%
Surface climatic conditions are key determinants of arthropod vector distribution and abundance and consequently affect transmission rates of any diseases they may carry. Remotely sensed observations by satellite sensors are the only feasible means of obtaining regional and continental scale measurements of climate at regular intervals for real-time epidemiological applications such as disease early warning systems. The potential of Pathfinder AVHRR Land (PAL) data to provide surrogate variables for near-surface air temperature and vapour pressure deficit (VPD) over Africa and Europe were assessed in this context. For the years 1988-1990 and 1992, correlations were examined between meteorological ground measurements (monthly mean air temperature and VPDgrd) and variables derived from Advanced Very High Resolution Radiometer (AVHRR) data (LST and VPDsat). The AVHRR indices were derived from both daily and composite PAL data so that their relative performance could be determined. Furthermore, the ground observations were divided into African and European subsets, so that the relative performance of the satellite data at tropical/sub-tropical and temperate latitudes could be assessed.

Comparison of Semi-Automated and Manual Measurements of Carotid Intima-Media Thickening

Mac Ananey, Oscar; Mellotte, Greg; Maher, Vincent
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
25.94%
Carotid intima-media thickening (CIMT) is a marker of both arteriosclerotic and atherosclerotic risks. Technological advances have semiautomated CIMT image acquisition and quantification. Studies comparing manual and automated methods have yielded conflicting results possibly due to plaque inclusion in measurements. Low atherosclerotic risk subjects (n = 126) were recruited to minimise the effect of focal atherosclerotic lesions on CIMT variability. CIMT was assessed by high-resolution B-mode ultrasound (Philips HDX7E, Phillips, UK) images of the common carotid artery using both manual and semiautomated methods (QLAB, Phillips, UK). Intraclass correlation coefficient (ICC) and the mean differences of paired measurements (Bland-Altman method) were used to compare both methodologies. The ICC of manual (0.547 ± 0.095 mm) and automated (0.524 ± 0.068 mm) methods was R = 0.74 and an absolute mean bias ± SD of 0.023 ± 0.052 mm was observed. Interobserver and intraobserver ICC were greater for automated (R = 0.94 and 0.99) compared to manual (R = 0.72 and 0.88) methods. Although not considered to be clinically significant, manual measurements yielded higher values compared to automated measurements. Automated measurements were more reproducible and showed lower interobserver variation compared to manual measurements. These results offer important considerations for large epidemiological studies.

Diesel Exhaust Exposure and the Risk of Lung Cancer—A Review of the Epidemiological Evidence

Sun, Yi; Bochmann, Frank; Nold, Annette; Mattenklott, Markus
Fonte: MDPI Publicador: MDPI
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
25.98%
To critically evaluate the association between diesel exhaust (DE) exposure and the risk of lung cancer, we conducted a systematic review of published epidemiological evidences. To comprehensively identify original studies on the association between DE exposure and the risk of lung cancer, literature searches were performed in literature databases for the period between 1970 and 2013, including bibliographies and cross-referencing. In total, 42 cohort studies and 32 case-control studies were identified in which the association between DE exposures and lung cancer was examined. In general, previous studies suffer from a series of methodological limitations, including design, exposure assessment methods and statistical analysis used. A lack of objective exposure information appears to be the main problem in interpreting epidemiological evidence. To facilitate the interpretation and comparison of previous studies, a job-exposure matrix (JEM) of DE exposures was created based on around 4,000 historical industrial measurements. The values from the JEM were considered during interpretation and comparison of previous studies. Overall, neither cohort nor case-control studies indicate a clear exposure-response relationship between DE exposure and lung cancer. Epidemiological studies published to date do not allow a valid quantification of the association between DE and lung cancer.

Need for Better Blood Pressure Measurement in Developing Countries to Improve Prevention of Cardiovascular Disease

Modesti, Pietro Amedeo; Perruolo, Eleonora; Parati, Gianfranco
Fonte: Japan Epidemiological Association Publicador: Japan Epidemiological Association
Tipo: Artigo de Revista Científica
Publicado em 05/02/2015 EN
Relevância na Pesquisa
25.93%
Hypertension is now the foremost cause of disability and is responsible for the highest percentage of attributable death among risk factors. These global changes are mainly due to the increase in the prevalence of hypertension in most low- and middle-income countries (LMICs) as a consequence of relevant socioeconomic changes occurring during the last decades. Implementation of global prevention efforts urgently needs to be accelerated because of the increasing incidence of haemorrhagic stroke, renal failure, and hypertensive heart disease in developing countries. Blood pressure (BP) measurement has different implications in epidemiological studies performed in low-resource settings. First, the frequency of blood pressure measurement is a simple but reliable indicator of access to healthcare in epidemiological studies, which may disclose the favourable effects of urbanization; the opportunity to have BP measured increases hypertension awareness, facilitates drug treatment, and leads to better achievement of BP control. Second, BP measurement is a key element in cardiovascular risk stratification, focusing solely on the preferred strategy in low-resource settings where costs of biochemical tests might be less sustainable. Third, the issue of obtaining reliable estimation of BP values is crucial to achieve sound data on the burden of hypertension in LMICs...

Cycloplegic refraction is the gold standard for epidemiological studies

Morgan, Ian G.; Iribarren, Rafael; Fotouhi, Akbar; Grzybowski, Andrzej
Fonte: Wiley Publicador: Wiley
Tipo: Artigo de Revista Científica Formato: 5
Relevância na Pesquisa
35.93%
Many studies on children have shown that lack of cycloplegia is associated with slight overestimation of myopia and marked errors in estimates of the prevalence of emmetropia and hyperopia. Non-cycloplegic refraction is particularly problematic for studies of associations with risk factors. The consensus around the importance of cycloplegia in children left undefined at what age, if any, cycloplegia became unnecessary. It was often implicitly assumed that cycloplegia is not necessary beyond childhood or early adulthood, and thus, the protocol for the classical studies of refraction in older adults did not include cycloplegia. Now that population studies of refractive error are beginning to fill the gap between schoolchildren and older adults, whether cycloplegia is required for measuring refractive error in this age range, needs to be defined. Data from the Tehran Eye Study show that, without cycloplegia, there are errors in the estimation of myopia, emmetropia and hyperopia in the age range 20-50, just as in children. Similar results have been reported in an analysis of data from the Beaver Dam Offspring Eye Study. If the only important outcome measure of a particular study is the prevalence of myopia, then cycloplegia may not be crucial in some cases. But...

Results of epidemiological studies of blood pressure are biased by continuous variation in arm size related to body mass

Ulijaszek, S.; Henneberg, M.
Fonte: Wayne State Univ Press Publicador: Wayne State Univ Press
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
25.93%
In cross-sectional epidemiological studies, blood pressure (BP) is often found to be positively correlated with fatness. Usually sphygmomanometers with only one cuff size for adults are used to measure BP while arm circumference (AC) influences BP readings. We have studied cross-sectional anthropometric and BP data of adult men and women from three populations: Cook Islanders (n = 259), Papua New Guinean: Purari (n = 295), and Ok Tedi (n = 274). These were selected because of their diverse socio-economic, anthropometric, and BP characteristics. Partial correlations and regressions were used to analyze these data. Systolic and diastolic pressures (SBP, DBP) showed dependence on AC, body mass index (BMI), and skinfold thickness. Stature had some effect on SBP and DBP, independent of BMI and AC. When effects of AC and stature were statistically controlled, BMI did not correlate with either SBP or DBP. People of larger body mass have greater AC, and this biases BP readings. Average values of SBP and DBP in groups of underweight, normal, overweight, and obese people predicted by AC (sex, age, and BMI being statistically controlled) closely matched observed SBP and DBP averages in those groups. Out of 24 pairwise comparisons (3 samples from different populations × 4 groups of BMI × 2 pressure readings) of predicted and actual BP...

The undesirable consequences of controlling for birth weight in perinatal epidemiological studies.

Blair, E
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1996 EN
Relevância na Pesquisa
25.93%
OBJECTIVE: To compare the effects of controlling for birth weight with those of controlling for gestational age at delivery in perinatal epidemiological studies using two examples. SETTING: Western Australia. SUBJECTS: Population data: all white births born at 20-46 weeks of gestation in Western Australia during 1985-91 inclusive (n = 147564). Example 1: All Western Australian births from 1980-89 born either at 33-36 weeks inclusive (n = 13607), or born with a birth weight of 2050-2900 g (n = 34107). Example 2: 160 singleton cases of spastic cerebral palsy born to white mothers in Western Australia from 1975-80 and whose gestational age was known, compared with (a) 480 controls individually matched for gender and birth weight and (b) singletons with known gestational age liveborn to white mothers in Western Australia from 1980-81, or 1979-82 if < 30 weeks' gestational age at birth (n = 32031). MEASUREMENTS AND MAIN RESULTS: The risks of cerebral palsy associated with two separate exposures in groups defined by birth weight were compared with those in groups defined by gestational age. The origin of the differences are explained using total population data. The estimates of risk differ when exposure and outcome are both associated with appropriateness of fetal growth. The difference varied with gestational age...

Serum Biomarkers of (Anti)Oxidant Status for Epidemiological Studies

Jansen, Eugène; Ruskovska, Tatjana
Fonte: MDPI Publicador: MDPI
Tipo: Artigo de Revista Científica
Publicado em 16/11/2015 EN
Relevância na Pesquisa
26.03%
In this review, we disclose a selection of serum/plasma biomarkers of (anti)oxidant status related to nutrition, which can be used for measurements in large-scale epidemiological studies. From personal experience, we have come to the following proposal of a set of biomarkers for nutritional intake, (anti)oxidant status, and redox status. We have selected the individual antioxidant vitamins E and A, and the carotenoids which can be measured in large series by HPLC. In addition, vitamin C was selected, which can be measured by an auto-analyzer or HPLC. As a biomarker for oxidative stress, the ROM assay (reactive oxygen metabolites) was selected; for the redox status, the total thiol assay; and for the total antioxidant status the BAP assay (biological antioxidant potential). All of these biomarkers can be measured in large quantities by an auto-analyzer. Critical points in biomarker validation with respect to blood sampling, storage conditions, and measurements are discussed. With the selected biomarkers, a good set is presented for use in the risk assessment between nutrition and (chronic) diseases in large-scale epidemiological studies. Examples of the successful application of these biomarkers in large international studies are presented.

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 EN
Relevância na Pesquisa
36.14%
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.