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911.
The availability of knowledge translation strategies that have been empirically studied and proven useful is a critical prerequisite to narrowing the research-to-practice gap in child and youth mental health. Through this review the authors sought to determine the current state of scientific knowledge of the effectiveness of knowledge translation approaches in child and youth mental health by conducting a systematic review of the research evidence. The findings and quality of the 12 included studies are discussed. Future work of high methodological quality that explores a broader range of knowledge translation strategies and practitioners to which they are applied and that also attends to implementation process is recommended.  相似文献   
912.
This study describes the motor-learning process of older individuals during the course of a training intervention on a motor-driven eccentric bicycle ergometer. Seventeen women and 16 men (64 ± 6 yr) took part in a 10-wk training program. Uniformity of force production and consistency of timing were used to describe their motor performance. The results suggested that participants improved the coefficient of variation of peak force during the intervention (measured at the 2nd, 4th, 6th, 8th, 10th, 12th, and the 18th training sessions). They reached a fairly constant level of motor performance around the 12th training session (5 wk). Age and sex affected improvements in the early phases of the learning process to an extent, but the differences diminished by the end of the intervention. These results suggest that the force control of continuous eccentric muscle contractions improves as a result of training in older adults.  相似文献   
913.
914.
察合台文史学名著《伊米德史》《安宁史》及其史料来源   总被引:1,自引:0,他引:1  
察合台文历史名著《伊米德史》和《安宁史》是作者基于长期的田野经历,并结合丰富的历史文献完成的宏篇巨著。文章从史籍、田野、口碑等三个角度对《伊米德史》和《安宁史》的史料来源进行了分析,重点论述了此书中所出现的史籍,并力图澄清其来源及出处,这对于研究维吾尔族史学史具有重大意义。  相似文献   
915.
In this paper we consider nonparametric estimation of transition probabilities for multi-state models. Specifically, we focus on the illness-death or disability model. The main novelty of the proposed estimators is that they do not rely on the Markov assumption, typically assumed to hold in a multi-state model. We investigate the asymptotic properties of the introduced estimators, such as their consistency and their convergence to a normal law. Simulations demonstrate that the new estimators may outperform Aalen–Johansen estimators (the classical nonparametric tool for estimating the transition probabilities) in non-Markov situation. An illustration through real data analysis is included.  相似文献   
916.
Recurrent event data often arise in biomedical studies, with examples including hospitalizations, infections, and treatment failures. In observational studies, it is often of interest to estimate the effects of covariates on the marginal recurrent event rate. The majority of existing rate regression methods assume multiplicative covariate effects. We propose a semiparametric model for the marginal recurrent event rate, wherein the covariates are assumed to add to the unspecified baseline rate. Covariate effects are summarized by rate differences, meaning that the absolute effect on the rate function can be determined from the regression coefficient alone. We describe modifications of the proposed method to accommodate a terminating event (e.g., death). Proposed estimators of the regression parameters and baseline rate are shown to be consistent and asymptotically Gaussian. Simulation studies demonstrate that the asymptotic approximations are accurate in finite samples. The proposed methods are applied to a state-wide kidney transplant data set.  相似文献   
917.
OBJECTIVES: To examine public response to a telephone screener used to identify a probability sample of lesbians, gays, and bisexuals. METHODS: A telephone screener was designed to provide a representative sample of self-identified lesbians, gays, and bisexuals (LGB) in the 30 central cities of the 15 largest Consolidated Metropolitan Areas. RESULTS: Of 14,458 households contacted, 11,612 completed at least part of the survey. Of these, only 2.6% refused or responded "don't know" to the sexual orientation screener question. Respondents from the northeast were more reluctant to answer than respondents from the west. CONCLUSIONS: The use of a screener on a national telephone survey to screen households for self-identified lesbian, gay, and bisexual adults was a successful way to generate a representative sample.  相似文献   
918.
Chen J  Xie Z  Liu H 《Population studies》2007,61(2):161-183
This study assesses the effects of socio-economic conditions and the interaction between son preference and China's one-child family planning policy on the use of maternal health care services and their effects on infant mortality in rural China, using nationally representative data from the 2001 National Family Planning and Reproductive Health Survey. The results show that while the use of maternal health care services has continued to increase over time, large gaps still exist in the use of these services and in infant survival by mother's education, community income, and parity. Further improvements in the reproductive health of all women and in infant survival will require effective reduction of the obstacles to the use of maternal health care among those women in rural China who are less educated, poor, and of higher parity.  相似文献   
919.
Manlove J  Ryan S  Franzetta K 《Demography》2007,44(3):603-621
By using data from the National Longitudinal Study of Adolescent Health, we examine how adolescent relationship characteristics, partner attributes, and sexual relationship histories are associated with contraceptive use and consistency, incorporating random effects to control for respondent-level unobserved heterogeneity. Analyses show that teens' contraceptive use patterns vary across relationships. Teens with more-homogamous partners, with more-intimate relationships, and who communicate about contraception before sex have greater odds of contraceptive use and/or consistency. Teens in romantic relationships, and who are older when engaging in sex for the first time, have greater odds of ever using contraceptives but reduced odds of always using contraceptives. Teens continue habits from previous relationships: teens with experience practicing contraceptive consistency and females who previously have used hormonal contraceptive methods are better able to maintain consistency in subsequent relationships. Also, relationship and partner characteristics are less important for females who previously used hormonal methods.  相似文献   
920.
We consider situations in which externally observable characteristics allow experts to quickly categorize individual households as likely or unlikely to contain a member of a rare target population. This classification can form the basis of disproportionate stratified sampling such that households classified as "unlikely" are sampled at a lower rate than those classified as "likely," thereby reducing screening costs. Design weights account for this approach and allow unbiased estimates for the target population.We demonstrate that with sensitivity and specificity of expert classification at least 70%, and ideally at least 80%, our approach can economically increase effective sample size for a rare population. We develop heuristics for implementing this approach and demonstrate that sensitivity drives design effects and screening costs whereas specificity only drives the latter. We demonstrate that the potential gains from this approach increase as the target population becomes rarer. We further show that for most applications, unlikely strata should be sampled at 1/6 to ? the rate of likely strata.This approach was applied to a survey of Cambodian immigrants in which the 82% of households rated "unlikely" were sampled at ? the rate as "likely" households, reducing screening from 9.4 to 4.0 approaches per complete. Sensitivity and specificity were 86% and 91% respectively. Weighted estimation had a design effect of 1.26 so screening costs per effective sample size were reduced 47%. We also note that in this instance, expert classification appeared to be uncorrelated with survey outcomes of interest among eligibles.  相似文献   
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