931 resultados para Future value prediction
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Although both inflammatory and atherosclerosis markers have been associated with coronary heart disease (CHD) risk, data directly comparing their predictive value are limited. The authors compared the value of 2 atherosclerosis markers (ankle-arm index (AAI) and aortic pulse wave velocity (aPWV)) and 3 inflammatory markers (C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha)) in predicting CHD events. Among 2,191 adults aged 70-79 years at baseline (1997-1998) from the Health, Aging, and Body Composition Study cohort, the authors examined adjudicated incident myocardial infarction or CHD death ("hard" events) and "hard" events plus hospitalization for angina or coronary revascularization (total CHD events). During 8 years of follow-up between 1997-1998 and June 2007, 351 participants developed total CHD events (197 "hard" events). IL-6 (highest quartile vs. lowest: hazard ratio = 1.82, 95% confidence interval: 1.33, 2.49; P-trend < 0.001) and AAI (AAI </= 0.9 vs. AAI 1.01-1.30: hazard ratio = 1.57, 95% confidence interval: 1.14, 2.18) predicted CHD events above traditional risk factors and modestly improved global measures of predictive accuracy. CRP, TNF-alpha, and aPWV had weaker associations. IL-6 and AAI accurately reclassified 6.6% and 3.3% of participants, respectively (P's </= 0.05). Results were similar for "hard" CHD, with higher reclassification rates for AAI. IL-6 and AAI are associated with future CHD events beyond traditional risk factors and modestly improve risk prediction in older adults.
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OBJECTIVES: Therapeutic hypothermia and pharmacological sedation may influence outcome prediction after cardiac arrest. The use of a multimodal approach, including clinical examination, electroencephalography, somatosensory-evoked potentials, and serum neuron-specific enolase, is recommended; however, no study examined the comparative performance of these predictors or addressed their optimal combination. DESIGN: Prospective cohort study. SETTING: Adult ICU of an academic hospital. PATIENTS: One hundred thirty-four consecutive adults treated with therapeutic hypothermia after cardiac arrest. MEASUREMENTS AND MAIN RESULTS: Variables related to the cardiac arrest (cardiac rhythm, time to return of spontaneous circulation), clinical examination (brainstem reflexes and myoclonus), electroencephalography reactivity during therapeutic hypothermia, somatosensory-evoked potentials, and serum neuron-specific enolase. Models to predict clinical outcome at 3 months (assessed using the Cerebral Performance Categories: 5 = death; 3-5 = poor recovery) were evaluated using ordinal logistic regressions and receiving operator characteristic curves. Seventy-two patients (54%) had a poor outcome (of whom, 62 died), and 62 had a good outcome. Multivariable ordinal logistic regression identified absence of electroencephalography reactivity (p < 0.001), incomplete recovery of brainstem reflexes in normothermia (p = 0.013), and neuron-specific enolase higher than 33 μg/L (p = 0.029), but not somatosensory-evoked potentials, as independent predictors of poor outcome. The combination of clinical examination, electroencephalography reactivity, and neuron-specific enolase yielded the best predictive performance (receiving operator characteristic areas: 0.89 for mortality and 0.88 for poor outcome), with 100% positive predictive value. Addition of somatosensory-evoked potentials to this model did not improve prognostic accuracy. CONCLUSIONS: Combination of clinical examination, electroencephalography reactivity, and serum neuron-specific enolase offers the best outcome predictive performance for prognostication of early postanoxic coma, whereas somatosensory-evoked potentials do not add any complementary information. Although prognostication of poor outcome seems excellent, future studies are needed to further improve prediction of good prognosis, which still remains inaccurate.
The 5th anniversary of "Patient Safety in Surgery" - from the Journal's origin to its future vision.
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A prospective study was undertaken to determine prognostic markers for patients with obstructive jaundice. Along with routine liver function tests, antipyrine clearance was determined in 20 patients. Four patients died after basal investigations. Five patients underwent definitive surgery. The remaining 11 patients were subjected to percutaneous transhepatic biliary decompression. Four patients died during the drainage period, while surgery was carried out for seven patients within 1-3 weeks of drainage. Of 20 patients, only six patients survived. Basal liver function tests were comparable in survivors and nonsurvivors. Discriminant analysis of the basal data revealed that plasma bilirubin, proteins and antipyrine half-life taken together had a strong association with mortality. A mathematical equation was derived using these variables and a score was computed for each patient. It was observed that a score value greater than or equal to 0.84 indicated survival. Omission of antipyrine half-life from the data, however, resulted in prediction of false security in 55% of patients. This study highlights the importance of addition of antipyrine elimination test to the routine liver function tests for precise identification of high risk patients.
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Background: Screening of elevated blood pressure (BP) in children has been advocated to early identify hypertension. However, identification of children with sustained elevated BP is challenging due to the high BP variability. The value of an elevated BP measure during childhood and adolescence for the prediction of future elevated BP is not well described. Objectives: We assessed the positive (PPV) and negative (NPV) predictive value of high BP for sustained elevated BP in cohorts of children of the Seychelles, a rapidly developing island state in the African region. Methods: Serial school-based surveys of weight, height, and BP were conducted yearly between 1998-2006 among all students of the country in four school grades (kindergarten [G0, mean age (SD): 5.5 (0.4) yr], G4 [9.2 (0.4) yr], G7 [12.5 (0.4) yr] and G10 (15.6 (0.5) yr]. We constituted three cohorts of children examined twice at 3-4 years interval: 4,557 children examined at G0 and G4, 6,198 at G4 and G7, and 6,094 at G7 and G10. The same automated BP measurement devices were used throughout the study. BP was measured twice at each exam and averaged. Obesity and elevated BP were defined using the CDC (BMI_95th sex-, and age-specific percentile) and the NHBPEP criteria (BP_95th sex-, age-, and height specific percentile), respectively. Results: Prevalence of obesity was 6.1% at G0, 7.1% at G4, 7.5% at G7, and 6.5% at G10. Prevalence of elevated BP was 10.2% at G0, 9.9% at G4, 7.1% at G7, and 8.7% at G10. Among children with elevated BP at initial exam, the PPV of keeping elevated BP was low but increased with age: 13% between G0 and G4, 19% between G4 and G7, and 27% between G7 and G10. Among obese children with elevated BP, the PPV was higher: 33%, 35% and 39% respectively. Overall, the probability for children with normal BP to remain in that category 3-4 years later (NPV) was 92%, 95%, and 93%, respectively. By comparison, the PPV for children initially obese to remain obese was much higher at 71%, 71%, and 62% (G7-G10), respectively. The NPV (i.e. the probability of remaining at normal weight) was 94%, 96%, and 98%, respectively. Conclusion: During childhood and adolescence, having an elevated BP at one occasion is a weak predictor of sustained elevated BP 3-4 years later. In obese children, it is a better predictor.
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Cardiovascular risk assessment might be improved with the addition of emerging, new tests derived from atherosclerosis imaging, laboratory tests or functional tests. This article reviews relative risk, odds ratios, receiver-operating curves, posttest risk calculations based on likelihood ratios, the net reclassification improvement and integrated discrimination. This serves to determine whether a new test has an added clinical value on top of conventional risk testing and how this can be verified statistically. Two clinically meaningful examples serve to illustrate novel approaches. This work serves as a review and basic work for the development of new guidelines on cardiovascular risk prediction, taking into account emerging tests, to be proposed by members of the 'Taskforce on Vascular Risk Prediction' under the auspices of the Working Group 'Swiss Atherosclerosis' of the Swiss Society of Cardiology in the future.
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This paper addresses primary care physicians, cardiologists, internists, angiologists and doctors desirous of improving vascular risk prediction in primary care. Many cardiovascular risk factors act aggressively on the arterial wall and result in atherosclerosis and atherothrombosis. Cardiovascular prognosis derived from ultrasound imaging is, however, excellent in subjects without formation of intimal thickening or atheromas. Since ultrasound visualises the arterial wall directly, the information derived from the arterial wall may add independent incremental information to the knowledge of risk derived from global risk assessment. This paper provides an overview on plaque imaging for vascular risk prediction in two parts: Part 1: Carotid IMT is frequently used as a surrogate marker for outcome in intervention studies addressing rather large cohorts of subjects. Carotid IMT as a risk prediction tool for the prevention of acute myocardial infarction and stroke has been extensively studied in many patients since 1987, and has yielded incremental hazard ratios for these cardiovascular events independently of established cardiovascular risk factors. However, carotid IMT measurements are not used uniformly and therefore still lack widely accepted standardisation. Hence, at an individual, practicebased level, carotid IMT is not recommended as a risk assessment tool. The total plaque area of the carotid arteries (TPA) is a measure of the global plaque burden within both carotid arteries. It was recently shown in a large Norwegian cohort involving over 6000 subjects that TPA is a very good predictor for future myocardial infarction in women with an area under the curve (AUC) using a receiver operating curves (ROC) value of 0.73 (in men: 0.63). Further, the AUC for risk prediction is high both for vascular death in a vascular prevention clinic group (AUC 0.77) and fatal or nonfatal myocardial infarction in a true primary care group (AUC 0.79). Since TPA has acceptable reproducibility, allows calculation of posttest risk and is easily obtained at low cost, this risk assessment tool may come in for more widespread use in the future and also serve as a tool for atherosclerosis tracking and guidance for intensity of preventive therapy. However, more studies with TPA are needed. Part 2: Carotid and femoral plaque formation as detected by ultrasound offers a global view of the extent of atherosclerosis. Several prospective cohort studies have shown that cardiovascular risk prediction is greater for plaques than for carotid IMT. The number of arterial beds affected by significant atheromas may simply be added numerically to derive additional information on the risk of vascular events. A new atherosclerosis burden score (ABS) simply calculates the sum of carotid and femoral plaques encountered during ultrasound scanning. ABS correlates well and independently with the presence of coronary atherosclerosis and stenosis as measured by invasive coronary angiogram. However, the prognostic power of ABS as an independent marker of risk still needs to be elucidated in prospective studies. In summary, the large number of ways to measure atherosclerosis and related changes in human arteries by ultrasound indicates that this technology is not yet sufficiently perfected and needs more standardisation and workup on clearly defined outcome studies before it can be recommended as a practice-based additional risk modifier.
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There are several alternatives for valuing the future opportunities of firms. The traditional appraisal methods for single projects such as net present value, internalrate of return and payback rules have been criticized in recent years. It has been said that they do not take into account all growth opportunities of firms. At the company level, business valuation is traditionally based on financial and market information. Yield estimates, net worth values and market values of shares are commonly used. Naturally, all valuation methods have their own strengths and shortcomings. In the background of most estimation rules there is the idea that the future of the firms is quite clear and predictable. However, in recent times the business environment of most companies has changed to a more unpredictable direction and the effects of uncertainty have increased. There has been a growing interest in estimating the risks and values of future possibilities. The aim of the current paper is to describe the difference between the value of futureopportunities in information technology firms and forest companies, and also toanalyse the backgrounds for the observed gap.
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Georgia is known for its extraordinary rich biodiversity of plants, which may now be threatened due to the spread of invasive alien plants (IAP). We aimed to identify (i) the most prominent IAP out of 9 selected potentially invasive and harmful IAP IAP by predicting thetheir distribution of 9 selected IAP under current and future climate conditions in Georgia as well as in its 43 Protected Areas, as a proxy for areas of high conservation value and (ii) the Protected Areas most at risk due to these IAP. We used species distribution models based on 6 climate variables and then filtered the obtained distributions based on maps of soil and vegetation types, and on recorded occurrences, resulting into the predicted ecological distribution of the 9 IAP's at a resolution of 1km2. We foundOur habitat suitability analysis showed that Ambrosia artemisiifolia, (24% and 40%) Robinia pseudoacaia (14% and 19%) and Ailanthus altissima (9% and 11%) have the largest potential distribution are the most abundant (predicted % area covered)d) IAP, with Ailanthus altissima the potentially most increasing one over the next fifty years (from 9% to 13% and from 11% to 25%), for Georgia and the Protected Areas, respectively. Furthermore, our results show indicate two areas in Georgia that are under specifically high threat, i.e. the area around Tbilisi and an area in the western part of Georgia (Adjara), both at lower altitudes. Our procedure to identify areas of high conservation value most at risk by IAP has been applied for the first time. It will help national authorities in prioritizing their measures to protect Georgia's outstanding biodiversity from the negative impact of IAP.
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Personality traits and personal values are two important domains of individual differences. Traits are enduring and distinguishable patterns of behaviour whereas values are societally taught, stable, individual preferences that guide behaviour in order to reach a specific end state. The purpose of the present study was to investigate the relations between self and peer report within the domains of personality traits and values, to examine the correlations between values and traits, and to explore the amount of incremental validity of traits and values in predicting behaviour. Two hundred and fiftytwo men and women from a university setting completed self and peer reports on three questionnaires. In order to assess personality traits, the HEXACO-PI (Lee & Ashton, 2004) was used to identify levels of 6 major dimensions of personality in participants. To assess values, the Schwartz Value Survey (Schwartz, 1992) was used to identify the importance each participant placed on each of Schwartz's 10 value types. To measure behaviour, a Behavior Scale, created by Bardi and Schwartz (2003), consisting of items designed to measure the frequency of value-expressive behaviour was used. As expected, correlations between self and peer reports for the personality scales were high indicating that personality traits are easily observable to other people. Correlations between self and peer reports for the values and behaviour scales were only moderate, suggesting that some goals, and behaviours expressive of those goals, may not always be observable to others. Consistent with previous research, there were many strong correlations between traits and values. In addition to the similarities with past research, the present study found that the personality factor Honesty-Humility was correlated strongly with values scales (with five correlations exceeding .25). In the prediction of behaviour, it was found that both personahty and values were able to account for significant and similar amounts of variance. Personality outpredicted values for some behaviours, but the opposite was true of other behaviours. Each domain provided incremental validity beyond the other domain. The impUcations for these findings, along with limitations, and possibilities for future research are also discussed.
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Learning disability (LD) is a neurological condition that affects a child’s brain and impairs his ability to carry out one or many specific tasks. LD affects about 10% of children enrolled in schools. There is no cure for learning disabilities and they are lifelong. The problems of children with specific learning disabilities have been a cause of concern to parents and teachers for some time. Just as there are many different types of LDs, there are a variety of tests that may be done to pinpoint the problem The information gained from an evaluation is crucial for finding out how the parents and the school authorities can provide the best possible learning environment for child. This paper proposes a new approach in artificial neural network (ANN) for identifying LD in children at early stages so as to solve the problems faced by them and to get the benefits to the students, their parents and school authorities. In this study, we propose a closest fit algorithm data preprocessing with ANN classification to handle missing attribute values. This algorithm imputes the missing values in the preprocessing stage. Ignoring of missing attribute values is a common trend in all classifying algorithms. But, in this paper, we use an algorithm in a systematic approach for classification, which gives a satisfactory result in the prediction of LD. It acts as a tool for predicting the LD accurately, and good information of the child is made available to the concerned
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Recognizing that high satisfaction leads to high customer loyalty, companies today are aiming for total customer satisfaction. This article explains relative impact of product quality, service quality and contextual experience on customer perceived value and intention to shop in the future. The data has been collected using a questionnaire from 205 customers of a national retailer chain. The relative importance of product quality, service quality and contextual experience on customer perceived value and thus on customer preference and future intentions was measured using multiple regression. Also, the contribution of perceived value to preference and thus on future buying intention was also measured. Structural Equation Model (SEM) using Amos 4 was used to find the overall fitness of the model. It was found that product quality, service quality and contextual experience have a major influence on customer perceived value
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Samples of whole crop wheat (WCW, n = 134) and whole crop barley (WCB, n = 16) were collected from commercial farms in the UK over a 2-year period (2003/2004 and 2004/2005). Near infrared reflectance spectroscopy (NIRS) was compared with laboratory and in vitro digestibility measures to predict digestible organic matter in the dry matter (DOMD) and metabolisable energy (ME) contents measured in vivo using sheep. Spectral models using the mean spectra of two scans were compared with those using individual spectra (duplicate spectra). Overall NIRS accurately predicted the concentration of chemical components in whole crop cereals apart from crude protein. ammonia-nitrogen, water-soluble carbohydrates, fermentation acids and solubility values. In addition. the spectral models had higher prediction power for in vivo DOMD and ME than chemical components or in vitro digestion methods. Overall there Was a benefit from the use of duplicate spectra rather than mean spectra and this was especially so for predicting in vivo DOMD and ME where the sample population size was smaller. The spectral models derived deal equally well with WCW and WCB and Would he of considerable practical value allowing rapid determination of nutritive value of these forages before their use in diets of productive animals. (C) 2008 Elsevier B.V. All rights reserved.
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The retention of peatland carbon (C) and the ability to continue to draw down and store C from the atmosphere is not only important for the UK terrestrial carbon inventory, but also for a range of ecosystem services, the landscape value and the ecology and hydrology of ~15% of the land area of the UK. Here we review the current state of knowledge on the C balance of UK peatlands using several studies which highlight not only the importance of making good flux measurements, but also the spatial and temporal variability of different flux terms that characterise a landscape affected by a range of natural and anthropogenic processes and threats. Our data emphasise the importance of measuring (or accurately estimating) all components of the peatland C budget. We highlight the role of the aquatic pathway and suggest that fluxes are higher than previously thought. We also compare the contemporary C balance of several UK peatlands with historical rates of C accumulation measured using peat cores, thus providing a long-term context for present-day measurements and their natural year-on-year variability. Contemporary measurements from 2 sites suggest that current accumulation rates (–56 to –72 g C m–2 yr–1) are at the lower end of those seen over the last 150 yr in peat cores (–35 to –209 g C m–2 yr–1). Finally, we highlight significant current gaps in knowledge and identify where levels of uncertainty are high, as well as emphasise the research challenges that need to be addressed if we are to improve the measurement and prediction of change in the peatland C balance over future decades.