A principled methodology for solving imbalanced binary classification problems has been recently introduced. It permits to obtain high performance designs avoiding the risks of degradation that other ...procedures suffer from. The corresponding paper Benítez-Buenache et al. (2019) shows evidence of these facts by applying direct versions, using just one of the possible rebalancing techniques and applying full rebalancing.
In this contribution, we extend the above study for maximizing the performance of the resulting designs. To this end, we combine principled techniques in order to taking benefit from their different characteristics. The combination weights as well as the rebalance degree are selected by means of a simple (cross-validation) search. A number of experiments with different kinds of databases shows significant performance improvements. At the same time, the database characteristics that limit the performance improvements −such as small size and noisy samples− are detected.
•Combining different (neutral) principled rebalancing techniques is proposed.•The combination degree and the rebalancing intensity are found by cross validation.•Extensive experiments support the effectiveness of the proposal.•Shallow and deep neural networks and ensembles are used in the experiments.•The database characteristics that reduce combinations performance are detected.
•We introduce a generalized form of emphasis weights for building boosting ensembles.•The main novelty of this emphasis is the inclusion of an intensity regulation term.•The algorithm is easy and ...offers results never worse than standard boosting.•In a significant number of problems, the new algorithm outperforms Real Adaboost.•The algorithm is competitive with other computationally more intensive forms.
Boosting ensembles have deserved much attention because their high performance. But they are also sensitive to adverse conditions, such as noisy environments or the presence of outliers. A way to fight against their degradation is to modify the forms of the emphasis weighting which is applied to train each new learner. In this paper, we propose to use a general form for that emphasis function, which not only includes an error dependent and a proximity to the classification boundary dependent term, but also a constant value which serves to control how much emphasis is applied. Two convex combinations are used to consider these terms, and this makes possible to control their relative influence. Experimental results support the effectiveness of this general form of boosting emphasis.
•A principled method for imbalanced classification is presented.•The iff conditions for principled re-balancing are established.•Informed two-step re-balancing techniques are introduced.•Extensive ...examples support the analysis.
This contribution proves that neutral re-balancing mechanisms, that do not alter the likelihood ratio, and training discriminative machines using Bregman divergences as surrogate costs are necessary and sufficient conditions to estimate the likelihood ratio of imbalanced binary classification problems in a consistent manner. These two conditions permit the estimation of the theoretical Neyman–Pearson operating characteristic corresponding to the problem under study. In practice, a classifier operates at a certain working point corresponding to, for example, a given false positive rate. This perspective allows the introduction of an additional principled procedure to improve classification performance by means of a second design step in which more weight is assigned to the appropriate training samples. The paper includes a number of examples that demonstrate the performance capabilities of the methods presented, and concludes with a discussion of relevant research directions and open problems in the area.
The impact of cytomegalovirus infection in elderly subjects remains unclear. This study examined the relationship between humoral immune response to cytomegalovirus (CMV) and all-cause mortality in a ...cohort of elderly hospitalised patients.
Data were obtained from a random sample of 715 patients (≥65 years old) admitted for any cause in a third level hospital. Serum IgG antibody against CMV was determined by enzyme-linked immunosorbent (ELISA) assay.
A total of 480 deaths occurred in seropositive patients (n = 671) during a follow-up of 7.6 years (mean, 4.6); of which 112 patients died in-hospital or within 30 days after discharge (short-term mortality). For patients with CMV IgG antibody levels in the highest quartile compared with lower quartile, fully adjusted models showed that mortality was 1.40 times (95% CI 1.05-1.86) and 2.20 times (95% CI 1.15-4.21) higher, respectively. The exclusion of patients with cardiovascular disease (angina, myocardial infarction, heart failure, peripheral artery disease, or stroke) increases the risk of long-term (HR 2.22, 95% CI 1.36-3.62) and short-term mortality (OR 3.18, 95% CI 1.40-7.24).
Increased IgG antibody levels against CMV are associated with increased short and long-term mortality in elderly hospitalised patients, especially in patients without cardiovascular disease.
Key Messages
The outcome of elderly hospitalised patients in relation to CMV is unknown.
We demonstrate an association between increased anti-CMV IgG levels and mortality.
This association is greater in elderly patients without cardiovascular disease.
Abstract Sex hormone‐binding globulin (SHBG) is a homodimeric glycoprotein produced by the human liver and secreted into the systemic circulation where it binds with high affinity sex steroids ...regulating their availability in blood and accessibility to target tissues. Plasma SHBG levels are altered in metabolic disorders such as obesity, anorexia, and insulin resistance. Several reports have shown that diets in terms of total calories or fat, fiber, or protein content can alter plasma SHBG levels. However, there are many components in a diet that can affect SHBG gene expression in the liver. In order to unravel the molecular mechanisms by which diets regulate SHBG production, it would be necessary to analyze single diet components and/or nutritional factors. This review summarizes the recent advances in identifying different nutritional factors regulating SHBG production and the related molecular mechanism, as well as the clinical implications.
In Spain, family is the main source of care for dependent people. Numerous studies suggest that providing informal (unpaid) care during a prolonged period of time results in a morbidity-generating ...burden. Caregivers constitute a high-risk group that experiences elevated stress levels, which reduce their quality of life.Different strategies have been proposed to improve management of this phenomenon in order to minimize its impact, but definitive conclusions regarding their effectiveness are lacking.
A community clinical trial is proposed, with a 1-year follow-up period, that is multicentric, controlled, parallel, and with randomized allocation of clusters in 20 health care centers within the Community of Madrid. The study's objective is to evaluate the effectiveness of a standard care intervention in primary health care (intervention CuidaCare) to improve the quality of life of the caregivers, measured at 0, 6, and 12 months after the intervention.One hundred and forty two subjects (71 from each group) ≥65 years, identified by the nurse as the main caregivers, and who provide consent to participate in the study will be included.The main outcome variable will be perceived quality of life as measured by the Visual Analogue Scale (VAS) of EuroQol-5D (EQ-5D). The secondary outcome variables will be EQ-5D Dimensions, EQ-5D Index, nursing diagnosis, and Zarit's test. Prognostic variables will be recorded for the dependent patient and the caregiver.The principle analysis will be done by comparing the average change in EQ-5D VAS value before and after intervention between the two groups. All statistical tests will be performed as intention-to-treat. Prognostic factors' estimates will be adjusted by mixed-effects regression models. Possible confounding or effect-modifying factors will be taken into account.
Assistance for the caregiver should be integrated into primary care services. In order to do so, incorporating standard, effective interventions with relevant outcome variables such as quality of life is necessary. Community care nurses are at a privileged position to develop interventions like the proposed one.
This trial has been registered in ClinicalTrials.gov under code number NCT 01478295.
To assess the efficacy of abatacept (ABA) in RA patients with interstitial lung disease (ILD) (RA-ILD).
This was an observational, multicentre study of RA-ILD patients treated with at least one dose ...of ABA. ILD was diagnosed by high-resolution CT (HRCT). We analysed the following variables at baseline (ABA initiation), 12 months and at the end of the follow-up: Modified Medical Research Council (MMRC) scale (1-point change), forced vital capacity (FVC) or diffusion lung capacity for carbon monoxide (DLCO) (improvement or worsening ≥10%), HRCT, DAS on 28 joints evaluated using the ESR (DAS28ESR) and CS-sparing effect.
We studied 263 RA-ILD patients 150 women/113 men; mean (s.d.) age 64.6 (10) years. At baseline, they had a median duration of ILD of 1 (interquartile range 0.25-3.44) years, moderate or severe degree of dyspnoea (MMRC grade 2, 3 or 4) (40.3%), FVC (% of the predicted) mean (s.d.) 85.9 (21.8)%, DLCO (% of the predicted) 65.7 (18.3) and DAS28ESR 4.5 (1.5). The ILD patterns were: usual interstitial pneumonia (UIP) (40.3%), non-specific interstitial pneumonia (NSIP) (31.9%) and others (27.8%). ABA was prescribed at standard dose, i.v. (25.5%) or s.c. (74.5%). After a median follow-up of 12 (6-36) months the following variables did not show worsening: dyspnoea (MMRC) (91.9%); FVC (87.7%); DLCO (90.6%); and chest HRCT (76.6%). A significant improvement of DAS28ESR from 4.5 (1.5) to 3.1 (1.3) at the end of follow-up (P < 0.001) and a CS-sparing effect from a median 7.5 (5-10) to 5 (2.5-7.5) mg/day at the end of follow-up (P < 0.001) was also observed. ABA was withdrawn in 62 (23.6%) patients due to adverse events (n = 30), articular inefficacy (n = 27), ILD worsening (n = 3) and other causes (n = 2).
ABA may be an effective and safe treatment for patients with RA-ILD.
Most care for people with chronic or disabling conditions living in the community is provided in the family context, and this care is traditionally provided by women. Providing informal care has a ...negative impact on caregivers' quality of life, which adds to existing health inequalities associated with gender. The aim of this study was to analyze factors associated with the health-related quality of life of caregivers and to determine their differences in a gender-differentiated analysis.
An observational, cross-sectional, multicenter study was conducted in primary healthcare. A total of 218 caregivers aged 65 years or older were included, all of whom assumed the primary responsibility for caring for people with disabling conditions for at least 6 months per year and agreed to participate in the CuidaCare study. The dependent variable was health-related quality of life, assessed with the EQ-5D. The explanatory variables tested were grouped into sociodemographic variables, subjective burden, caregiving role, social support and variables related to the dependent person. The associations between these variables and health-related quality of life were estimated by fitting robust linear regression models. Separate analyses were conducted for women and men.
A total of 72.8% of the sample were women, and 27.2% were men. The mean score on the EQ-5D for female caregivers was 0.64 (0.31); for male caregivers, it was 0.79 (0.23). There were differences by gender in the frequency of reported problems in the dimensions of pain/comfort and anxiety/depression. The variables that were associated with quality of life also differed. Having a positive depression screening was negatively associated with quality of life for both genders: -0.31 points (95% CI: -0.47; -0.15) for female caregivers and -0.48 points (95% CI: -0.92; -0.03) for male caregivers. Perceived burden was associated with quality of life in the adjusted model for women (-0.12 points; 95% CI: -0.19; -0.06), and domestic help was associated in the adjusted model for male caregivers (-0.12 points; 95% CI: -0.19; -0.05).
Gender differences are present in informal caregiving. The impact of providing informal care is different for male and female caregivers, and so are the factors that affect their perceived quality of life. It could be useful it incorporates a gender perspective in the design of nursing support interventions for caregivers to individualize care and improve the quality of life of caregivers.
NCT01478295 https://ClinicalTrials.gov . 23/11/2011.
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