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941.
Therapeutic residential care (TRC) is the name given to specialized children's homes for treating cases with severe emotional and behavioural problems that have been placed in residential care. A recent international review has revealed great diversity in the referral criteria of cases and in the models of intervention carried out. The goal of this study is to describe the population treated in these types of facilities in Spain and the therapeutic coverage given. The sample is made up of 215 young people in children's homes, of whom 93 are in TRC. The cases referred to TRC have been in residential care for less time but have gone through a greater number of placements. These young people also exhibit more problems of drug use, and there is a larger percentage of clinical‐range cases in the Child Behaviour Checklist scales of attention problems and aggressive behaviour. Nevertheless, the results of logistic regression indicate that the only variables that significantly increase the probability of being referred to TRC are drug use and changes of care placements. With regard to therapeutic care, there is a higher percentage in the TRC group receiving psychiatric care, and the sessions are also more frequent.  相似文献   
942.
The tobit model allows a censored response variable to be described by covariates. Its applications cover different areas such as economics, engineering, environment and medicine. A strong assumption of the standard tobit model is that its errors follow a normal distribution. However, not all applications are well modeled by this distribution. Some efforts have relaxed the normality assumption by considering more flexible distributions. Nevertheless, the presence of asymmetry could not be well described by these flexible distributions. A real-world data application of measles vaccine in Haiti is explored, which confirms this asymmetry. We propose a tobit model with errors following a Birnbaum–Saunders (BS) distribution, which is asymmetrical and has shown to be a good alternative for describing medical data. Inference based on the maximum likelihood method and a type of residual are derived for the tobit–BS model. We perform global and local influence diagnostics to assess the sensitivity of the maximum likelihood estimators to atypical cases. A Monte Carlo simulation study is carried out to empirically evaluate the performance of these estimators. We conduct a data analysis for the mentioned application of measles vaccine based on the proposed model with the help of the R software. The results show the good performance of the tobit–BS model.  相似文献   
943.
This article proposes wild and the independent and identically distibuted (i.i.d.) parametric bootstrap implementations of the time-varying cointegration test of Bierens and Martins (2010 Bierens, H. J., Martins, L. F. (2010). Time varying cointegration. Econometric Theory 26:14531490.[Crossref], [Web of Science ®] [Google Scholar]). The bootstrap statistics and the original likelihood ratio test share the same first-order asymptotic null distribution. Monte Carlo results suggest that the bootstrap approximation to the finite-sample distribution is very accurate, in particular for the wild bootstrap case. The tests are applied to study the purchasing power parity hypothesis for twelve Organisation for Economic Cooperation and Development (OECD) countries and we only find evidence of a constant long-term equilibrium for the U.S.–U.K. relationship.  相似文献   
944.
Two- or multi-phase study designs are often used in settings involving failure times. In most studies, whether or not certain covariates are measured on an individual depends on their failure time and status. For example, when failures are rare, case–cohort or case–control designs are used to increase the number of failures relative to a random sample of the same size. Another scenario is where certain covariates are expensive to measure, so they are obtained only for selected individuals in a cohort. This paper considers such situations and focuses on cases where we wish to test hypotheses of no association between failure time and expensive covariates. Efficient score tests based on maximum likelihood are developed and shown to have a simple form for a wide class of models and sampling designs. Some numerical comparisons of study designs are presented.  相似文献   
945.
The practice of pre-loading—drinking large amounts of alcohol rapidly in private spaces prior to socialising in the night-time economy—has come to notice recently in the study of alcohol-related harm, but no studies have explored these phenomena in Aotearoa New Zealand. We used a theoretical framework developed with public health alcohol studies for understanding drinking cultures that conceptualises patterns of behaviours as arising within a dynamic interaction between forces of hedonism, function and control. We report findings from 34 focus groups conducted with 18–25 year olds as part of a project supported by the Marsden Fund, between 2011 and 2012, to investigate drinking cultures among young people. Our thematic analyses of participants’ accounts of pre-loading show that the term is in common use, applying to a range of practices motivated by price of alcohol but influenced by the pleasures of intoxication, the importance of peer processes and certain aspects of the regulatory system. We conclude with a discussion of the usefulness of the framework and the implications of the findings for public health policy that aims to reduce alcohol consumption and the harm that arises from it.  相似文献   
946.
The problem of comparing several experimental treatments to a standard arises frequently in medical research. Various multi-stage randomized phase II/III designs have been proposed that select one or more promising experimental treatments and compare them to the standard while controlling overall Type I and Type II error rates. This paper addresses phase II/III settings where the joint goals are to increase the average time to treatment failure and control the probability of toxicity while accounting for patient heterogeneity. We are motivated by the desire to construct a feasible design for a trial of four chemotherapy combinations for treating a family of rare pediatric brain tumors. We present a hybrid two-stage design based on two-dimensional treatment effect parameters. A targeted parameter set is constructed from elicited parameter pairs considered to be equally desirable. Bayesian regression models for failure time and the probability of toxicity as functions of treatment and prognostic covariates are used to define two-dimensional covariate-adjusted treatment effect parameter sets. Decisions at each stage of the trial are based on the ratio of posterior probabilities of the alternative and null covariate-adjusted parameter sets. Design parameters are chosen to minimize expected sample size subject to frequentist error constraints. The design is illustrated by application to the brain tumor trial.  相似文献   
947.
We propose a new type of non-parametric density estimators fitted to random variables with lower or upper-bounded support. To illustrate the method, we focus on nonnegative random variables. The estimators are constructed using kernels which are densities of empirical means of m i.i.d. nonnegative random variables with expectation 1. The exponent m   plays the role of the bandwidth. We study the pointwise mean square error and propose a pointwise adaptive estimator. The risk of the adaptive estimator satisfies an almost oracle inequality. A noteworthy result is that the adaptive rate is in correspondence with the smoothness properties of the unknown density as a function on (0,+∞)(0,+). The adaptive estimators are illustrated on simulated data. We compare our approach with the classical kernel estimators.  相似文献   
948.
This study identifies perspectives of relationships publics have about countries other than their own and examines whether publics engaged through social media-based public diplomacy programs demonstrate different relationship perspectives. Q methodology and survey research were used to investigate these issues. Data come from South Korean adult internet users, including members of Café USA, an online community run by the U.S. Embassy in Seoul. Three relationship perspectives were identified: outcome-based, sincerity-based, and access-based. Compared with other groups, Café USA members put more emphasis on sincerity in their relationships with the United States. The results of this study indicate that individuals’ subjectivity should be considered as far more contextualized and nuanced than has been the case in previous research on national image or country reputation.  相似文献   
949.
Abstract

Objective: To assess the use of alcohol screening tools across US colleges. Participants: Directors of health services at 333 four-year colleges. Methods: An online survey was conducted regarding the use of alcohol screening tools. Schools reporting use of formal tools were further described in terms of 4 tools (AUDIT, CUGE, CAPS, and RAPS) that the authors judged to be the most favorable based on prior empirical comparative studies. Results: Forty-four percent of colleges reported use of at least 1 formal alcohol screening tool and nearly all of these used a tool appropriate for college students. However, less than half of the 44% of colleges that used a screening tool used 1 of the 4 most favorable tools. Conclusions: Continued efforts are needed to encourage colleges to use the most effective available screening tools to identify alcohol-related problems that require intervention among students.  相似文献   
950.
Abstract

“Single-Dose Therapy for Cystitis in Women: A Comparison of Trimethoprim-Sulfamethoxazole, Amoxicillin, and Cyclacillin,” Thomas M. Hooton et al. We evaluated single-dose regimens of trimethoprim-sulfamethoxazole, amoxicillin, and cyclacillin as treatment for acute cystitis in 38 women. The trial was prematurely stopped because of frequent treatment failures. At two days after treatment, all 13 patients given trimethoprim-sulfamethoxazole were cured, while four (31%) of the 13 given amoxicillin and four (33%) of 12 given cyclacillin had persistent bacteriuria. At two weeks, 11 (85%) of 13 patients given trimethoprim-sulfamethoxazole, six (50%) of 12 given amoxicillin, and three (30%) of ten given cyclacillin were cured. One patient with positive results of antibody-coated bacteria testing who was treated with cyclacillin had signs and symptoms of acute pyelonephritis three days after treatment, and two patients treated with amoxicillin and one treated with trimethoprim-sulfamethoxazole converted antibody-coated bacteria test results from negative to positive after therapy. We conclude that single-dose treatment of cystitis in unselected women with cyclacillin and amoxicillin may result in low cure rates and that progression to acute pyelonephritis may occur following ineffective single-dose therapy. (Journal of the American Medical Association 1985;253:387-390.)  相似文献   
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