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991.
In this paper we present an approach to using historical control data to augment information from a randomized controlled clinical trial, when it is not possible to continue the control regimen to obtain the most reliable and valid assessment of long term treatment effects. Using an adjustment procedure to the historical control data, we investigate a method of estimating the long term survival function for the clinical trial control group and for evaluating the long term treatment effect. The suggested method is simple to interpret, and particularly motivated in clinical trial settings when ethical considerations preclude the long term follow-up of placebo controls. A simulation study reveals that the bias in parameter estimates that arises in the setting of group sequential monitoring will be attenuated when long term historical control information is used in the proposed manner. Data from the first and second National Wilms' Tumor studies are used to illustrate the method. 相似文献
992.
Toon W. Taris 《Work and stress》2006,20(4):316-334
Previous research has suggested that high levels of burnout lead to impaired functioning on the job. However, as this research has usually relied on self-reported performance, it is imperative to examine whether this association is also confirmed when using “objective” performance data (e.g., supervisor reports). This study reviewed previous research on the associations between burnout (exhaustion, depersonalization, and personal accomplishment) and various types of objective performance. A systematic literature search identified 16 studies dealing with the burnout-performance relationship. These studies showed the wide variety of approaches that are used to study burnout and objective performance. Using data from these 16 studies, a meta-analysis was conducted to obtain mean correlations. The meta-analytical correlations between exhaustion and in-role behaviour (based on five studies), organizational citizenship behaviour (OCB; five studies), and customer satisfaction (two studies) were -.22, -.19, and -.55, respectively, underlining the practical relevance of burnout research for organizational performance. The evidence for the relationships between depersonalization, personal accomplishment, and performance was inconclusive. Future research should focus on valid indicators of job performance, should more often employ longitudinal designs and large samples, and should consider the theoretical basis for the study expectations more extensively. 相似文献
993.
A report of the 1989 NCDA survey of the perceptions of American adults of their career planning, the nature of their workplaces, and the availability of and utility of occupational information is presented. The survey, which was administered by the Gallup Organization, included an oversampling of Hispanics, African Americans, and Asian-Pacific Islanders. Although the results for all groups including Whites are presented, the emphasis is upon the perceptions of minority groups. 相似文献
994.
Nicolas W. Hengartner Marten H. Wegkamp Eric Matzner-Løber 《Journal of the Royal Statistical Society. Series B, Statistical methodology》2002,64(4):791-804
Summary. The paper presents a general strategy for selecting the bandwidth of nonparametric regression estimators and specializes it to local linear regression smoothers. The procedure requires the sample to be divided into a training sample and a testing sample. Using the training sample we first compute a family of regression smoothers indexed by their bandwidths. Next we select the bandwidth by minimizing the empirical quadratic prediction error on the testing sample. The resulting bandwidth satisfies a finite sample oracle inequality which holds for all bounded regression functions. This permits asymptotically optimal estimation for nearly any regression function. The practical performance of the method is illustrated by a simulation study which shows good finite sample behaviour of our method compared with other bandwidth selection procedures. 相似文献
995.
996.
R S Andersen 《Child welfare》1988,67(1):15-19
As both adoptee and psychiatrist, the author brings a double-barreled observation to the issue of search. 相似文献
997.
Beverly Burch M.S.W. 《Clinical Social Work Journal》1988,16(2):125-142
Kleinian theory seems both intimidating and alien to many American psychotherapists. This paper offers an entry into Klein's work. The theory is approached by emphasizing three areas especially valuable in clinical practice: mourning and manic defenses, schizoid relationships, and envy and idealization. A detailed presentation of an individual psychotherapy case is offered as an illustration of how her ideas may be integrated into a broader objectrelations treatment perspective. 相似文献
998.
Relationships among three motivational variables (negative-personal functions of drinking, alienation, and perceived discrepancies between valued goals and expected success toward valued goals) were evaluated in a group of 257 college drinkers. As predicted, a positive relationship between alienation scores and the extent of discrepancies between values and expectations for academic and social success was found. Negative-personal drinking functions were positively associated with both alienation and value-expectation discrepancies. Results are discussed in terms of heuristic consistency and potential applications. 相似文献
999.
1000.
Marianne Berry Ph.D. Richard P. Barth Ph.D. ACSW Barbara Needell M.S.W. 《Child and Adolescent Social Work Journal》1996,13(2):157-183
Information gathered from over 1000 adoptions in the fourth year of a prospective study of adoptions finds satisfaction levels to be quite high, with those families adopting through private agencies to feel best prepared and satisfied. Differences by adoption auspice are detailed and discussed.The senior authors are Co-Principal Investigators of the California Long-range Adoption Study. This research was supported by the Child Welfare Research Center, Family Welfare Research Group, University of California at Berkeley, through a grant from the Children's Bureau, Administration for Children and Families, Department of Health and Human Services. The authors wish to thank the families for their participation. Please address correspondence to Mary Berry at the Center for Child Welfare, UTA School of Social Work, P.O. Box 19129, Arlington, Texas 76019. 相似文献