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161.
The study of physicians as managed care executives has been relatively recent. Much of what was written in the past focused primarily on doctors who had taken hospital-based administrative positions, especially as medical directors or vice presidents of medical affairs.1 But the '80s brought rising health care costs and the emergence of the "O's"--HMOs, PPOs, UROs, EPOs, PHOs, H2Os, and Uh-Ohs--in response. It also brought a growing number of physicians who traded their white coats and their particular "ologies" for the blue suits of executive management. I am convinced that it is important now, and will be increasingly important in the future, to better understand that transition. That belief led me to undertake, with the help and support of ACPE, the survey that is reported in this article. A questionnaire was sent in 1994 to a random sample of 300 managed care physician executive members of ACPE. Responses were returned by 225 members, a response rate of better than 80 percent. Twenty-five of the responses were not applicable, having been returned by physicians who had never made a transition from clinical careers. The remaining 230 responses form the basis for this report.  相似文献   
162.
Consider a randomized trial in which time to the occurrence of a particular disease, say pneumocystis pneumonia in an AIDS trial or breast cancer in a mammographic screening trial, is the failure time of primary interest. Suppose that time to disease is subject to informative censoring by the minimum of time to death, loss to and end of follow-up. In such a trial, the censoring time is observed for all study subjects, including failures. In the presence of informative censoring, it is not possible to consistently estimate the effect of treatment on time to disease without imposing additional non-identifiable assumptions. The goals of this paper are to specify two non-identifiable assumptions that allow one to test for and estimate an effect of treatment on time to disease in the presence of informative censoring. In a companion paper (Robins, 1995), we provide consistent and reasonably efficient semiparametric estimators for the treatment effect under these assumptions. In this paper we largely restrict attention to testing. We propose tests that, like standard weighted-log-rank tests, are asymptotically distribution-free -level tests under the null hypothesis of no causal effect of treatment on time to disease whenever the censoring and failure distributions are conditionally independent given treatment arm. However, our tests remain asymptotically distribution-free -level tests in the presence of informative censoring provided either of our assumptions are true. In contrast, a weighted log-rank test will be an -level test in the presence of informative censoring only if (1) one of our two non-identifiable assumptions hold, and (2) the distribution of time to censoring is the same in the two treatment arms. We also extend our methods to studies of the effect of a treatment on the evolution over time of the mean of a repeated measures outcome, such as CD-4 count.  相似文献   
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Schools are centers of collaboration in promoting the development and learning of children and adolescents. They seek to develop cultures of collaboration not only within their walls but also among constituencies with similar interests. These efforts, unfortunately, all too often prove frustrating and disappointing to all concerned. Yet, the need for interdisciplinary inquiry is greater today than ever before. This is particularly true considering the complex, diverse, and multifaceted nature of today's schools. No one professional can address all of the problems confronting education, particularly those of urban schools. For decades mental health and education professionals have joined together around their similar interest in promoting children and adolescent development. One such initiative is a program that fosters educators' development. This program, named the Teacher Education Program, began under the auspices of the Chicago Institute for Psychoanalysis and evolved into the Human Development and Learning Program when a partnership was formed with DePaul University's School of Education. From the program's 34-year history, the authors highlight specific tensions they experienced as directors of this collaborative initiative, and how these challenges either were or were not anticipated and/or addressed. The aims are to put a human face on the challenges and struggles encountered in the relationship between education and mental health professionals, and to identify common ground between educational and psychoanalytic theories and practices.  相似文献   
167.
Responses to the Adult Career Concerns Inventory (ACCI: Super, Thompson, Lindeman, Myers, & Jordaan, 1988) were organized through cluster analysis to identify different ways in which adults use exploratory behavior to cope with career development tasks. Significant differences in life-role salience among the types of adult career explorers identified were also investigated. Findings indicated a variety of ways in which adults use exploratory behavior. However, no significant differences were found in life-role salience among the types of career explorers. The discussion explains how career counselors can interpret their clients' ACCI profiles to select appropriate career interventions.  相似文献   
168.
"Many studies highlight the macro-level dissemination of global culture and institutions. This article focuses on social remittances--a local-level, migration-driven form of cultural diffusion. Social remittances are the ideas, behaviors, identities, and social capital that flow from receiving- to sending-country communities. The role that these resources play in promoting immigrant entrepreneurship, community and family formation, and political integration is widely acknowledged. This article specifies how these same ideas and practices are remolded in receiving countries, the mechanisms by which they are sent back to sending communities, and the role they play in transforming sending-country social and political life." The data concern migrants from the Dominican Republic to the Boston area of the United States.  相似文献   
169.
This study explored the relationship between US immigration laws and their impact on the immigration of Asian professionals. The article relied on a 1996 Population Association presentation. Data were obtained from the US Immigration and Naturalization Service on legally admitted immigrants to the US. The authors describe the paths to admission, trends in immigration of professionals during 1972-94, and the Immigration Act of 1965 and its 4 amendments. Standardization-decomposition techniques are used to explain the relative differences in professional immigration across 1972-77, 1978-91, and 1992-94. The crude professional rate for all Asians declined by 19% during 1972-91. 62% of the decline was due to changes in the class of admission composition, and 25% was due to a decline in the class-specific professional rates. During 1992-94, the Asian crude professional rate increased 7%, most of which was due to changes in class composition, with the exception of Korean rates. Only the Vietnamese experienced a decline in rates. The 1965 law allowed for equity between countries in admission. The paths of immigration were family ties, job skills, or refugee status. During 1972-77, Chinese took advantage of family reunification, and Indians entered on employment preferences. The legal changes affected the size and share of each class of admission. The revisions indirectly affected the occupational selectivity of immigrant groups. 27% of the flow of Asians during 1972-77 was accounted for by employment preferences. Professionals were 44% of Asian immigrants during 1972-77, 26% during 1978-91, and 33% during 1992-94.  相似文献   
170.
A non-linear model for examining genotypic responses across an array of environments is contrasted with the 'joint regression' formulation, and a rigorous approach to hypothesis testing using the conditional error principle is demonstrated. The model is extended to cater for situations where single straight-line response patterns fail to characterize genotypic behaviors over an environmental array: a combination of two straight lines, with slope in below-average and in above-average environments, is offered as the 1 2 simplest representation of convex and concave patterns. A protocol for classifying genotypes according to the results of hypothesis tests, i.e. H( = ) and H( = = = 1), is 1 2 1 2 presented . A doubly desirable response pattern is convex ( < 1< ), while a doubly 1 2 undesirable pattern is concave ( > 1> ). 1 2  相似文献   
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