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11.
本文从有关研究证据的基础上,介绍了个人化设计的理论基础和实验设计,并在此基础上讨论了个人化设计在临床研究领域中的应用价值,总结出一种适合临床病人使用的研究程序。个人化设计允许对个体的个人价值进行分析,并能同时研究不同刺激信息的作用,在个体水平上分析个体差异。通过简化了的实验程序,个人化设计为解决临床研究中的问题提供了一种新的思维方式。文中还对相关研究法的局限进行了讨论。 相似文献
12.
David J. Doukas 《Theoretical medicine and bioethics》1992,13(1):5-14
The emergence of the ethics consultation as a means to resolve moral crises in clinical medicine has revealed the need for a worksheet that would facilitate intake and analysis. The author developed the Bioethics Consultation Form as an attempt to remedy this need. The form is arranged in an outline format and is a useful asset to ethics committee discussions and record keeping. The first section covers basic intake data concerning the patient's medical and personal information, advance directives, and values, as well as the values of the physician and family. After the intake section is completed with the above data, the ethics consultant then turns to the analysis section. This second section allows for (1) the discussion of conflicting values, (2) the identification of priorities, and (3) the elucidation of ethical norms relevant to the case.The Bioethics Consultation Form was adopted by the Patient Care Advisory committee of the Franklin Square Hospital Center in Baltimore, Maryland in 1986. The methodology in the use of the form will be discussed. Further, the potential spectrum of consultative cases that can be analyzed using the form will be highlighted. 相似文献
13.
Kenneth F. Schaffner 《Theoretical medicine and bioethics》1992,13(2):191-216
This two-part article examines the competition between the clonal selection theory and the instructive theory of the immune response from 1957–1967. In Part I the concept of a temporally extended theory is introduced, which requires attention to the hitherto largely ignored issue of theory individuation. Factors which influence the acceptability of such an extended theory at different temporal points are also embedded in a Bayesian framework, which is shown to provide a rational account of belief change in science. In Part II these factors, as elaborated in the Bayesian framework, are applied to the case of the success of the clonal selection theory and the failure of the instructive theory. 相似文献
14.
James Lindemann Nelson 《Theoretical medicine and bioethics》1992,13(4):319-328
Mary Anne Warren's claim that there is room for only one person with full and equal rights inside a single human skin ([1], p. 63) calls attention to the vast range of moral conflict engendered by assigning full basic moral rights to fetuses. Thereby, it serves as a goad to thinking about conflicts between pregnant women and their fetuses in a way that emphasizes relationships rather than rights. I sketch out what a care orientation might suggest about resolving gestational conflicts. I also argue that the care orientation, with its commitment to the significance of the partial and the particular, cannot be absorbed within standard, impartialist moral theory. 相似文献
15.
Norman Cliff 《Psychometrika》1989,54(1):75-91
This paper argues that test data are ordinal, that latent trait scores are only determined ordinally, and that test data are used largely for ordinal purposes. Therefore it is desirable to develop a test theory based only on ordinal assumptions. A set of ordinal assumptions is presented, including an ordinal version of local independence. From these assumptions it is first shown that the gamma-correlation between two tests is the product of their gamma-correlations with the true latent order. The theory is generalized to allow for heterogeneous tests by defining a weighted average local independence. The tau-correlations between total score and the latent order can be found in both homogeneous and heterogeneous cases, and a system of differential item weighting to maximize the tau-correlation between weighted items and the latent order is provided. Thus a purely ordinal test theory seems possible.Part of this work was done while the author was a Visiting Fellow at Macquarrie University. The paper has benefitted from discussions with Professors Thomas J. Reynolds and Roderick P. McDonald and from the comments of several anonymous reviewers. 相似文献
16.
Paul R. Rosenbaum 《Psychometrika》1989,54(4):625-633
Established results on latent variable models are applied to the study of the validity of a psychological test. When the test predicts a criterion by measuring a unidimensional latent construct, not only must the total score predict the criterion, but the joint distribution of criterion scores and item responses must exhibit a certain pattern. The presence of this population pattern may be tested with sample data using the stratified Wilcoxon rank sum test. Often, criterion information is available only for selected examinees, for instance, those who are admitted or hired. Three cases are discussed: (i) selection at random, (ii) selection based on the current test, and (iii) selection based on other measures of the latent construct. Discriminant validity is also discussed.This work was supported in part by Grant SES-87-01890 from the Measurement Methods and Data Improvement Program of the U.S. National Science Foundation. 相似文献
17.
We propose a method for detecting influential observations in iterative principal factor analysis. For this purpose we derive the influence functionsI(x; LL
T
) andI(x; ) for the common variance matrixT =LL
T
and the unique variance matrix , respectively, in the common factor decomposition =LL
T
+ . A numerical example is given for illustration.The authors are grateful to Tomoyuki Tarumi and Atsuhiro Hayashi for their kind permission to use their software Seto/B for drawing Figures 1 and 2 and to anonymous reviewers for comments on the paper. 相似文献
18.
Bengt O. Muthén 《Psychometrika》1989,54(3):385-396
The problem of detecting instructional sensitivity (item basis) in test items is considered. An illustration is given which shows that for tests with many biased items, traditional item bias detection schemes give a very poor assessment of bias. A new method is proposed instead. This method extends item response theory (IRT) by including item-specific auxiliary measurement information related to opportunity-to-learn. Item-specific variation in measurement relations across students with varying opportunity-to-learn is allowed for.This paper was presented at the 1987 AERA meeting in Washington, DC. This research was supported by grant OERI-G-86-003 from the Office of Educational Research and Improvement, Department of Education. The author thanks Michael Hollis and Chih-fen Kao for valuable research assistance, and appreciates valuable comments made by an anonymous reviewer. 相似文献
19.
20.
Mark H. Lewis Alfred A. Baumeister Richard B. Mailman 《Journal of applied behavior analysis》1987,20(3):253-258
A perceptual reinforcement theory of stereotyped movements is advanced by Lovaas, Newsom, and Hickman (1987) in an effort to integrate a number of diverse observations about the origins and maintenance of this behavior. We, in turn, argue that the theory, as presented, is logically flawed and fails to take into account important biological findings and theory concerning pathological stereotyped acts. An alternative theory, derived primarily from neurological concepts, is briefly described. 相似文献