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951.
Epidemiological studies have been cited in the literature as evidence both for and against the human cancer risks predicted by high-exposure rodent studies. However, there has been little overall consistency in the ways that these animal-to-human comparisons have been made. This review examines some examples of these types of comparisons and describes the methods and techniques used by different investigators. Eleven "key decision areas" that need to be addressed are identified and recommendations for consistent, logical, and statistically appropriate approaches that might be taken to standardize the process are provided. In general, it is suggested that investigators provide the most useful information when they use logical, transparent, and statistically valid comparisons to pursue limited and focused objectives, such as directly testing the validity of an existing regulatory guidance value. Other recommendations include selecting biologically plausible extrapolative models that fit the data and drawing conclusions that are consistent with the study results and objectives.  相似文献   
952.
A number of governments and public policy institutes have developed Quality of Life Indexes – statistics that attempt to measure the quality of life for entire states or regions. We develop 14 criteria for determining the validity and usefulness of such QOL indexes to public policy. We then review 22 of the most-used QOL indexes from around the world. We conclude that many of the indexes are successful in that they are reliable, have established time series measures, and can be disaggregated to study subpopulations. However, many fall short in four areas: (1) indexes vary greatly in their coverage and definitions of domains of QOL, (2) none of the indexes distinguish among the concepts of input, throughput, and output that are used by public policy analysts, (3) they fail to show how QOL outputs are sensitive to public policy inputs, and (4) none have examined convergent validity against each other. We conclude that many of these indexes are potentially very useful for public policy and recommend research to further improve them.  相似文献   
953.
Risk Perception in a Developing Country: The Case of Chile   总被引:2,自引:0,他引:2  
In this work we characterize risk perception in Chile, based on the psychometric paradigm, exploring the difference between perceived social and personal risk. For this purpose, we conducted a survey including 54 hazards, 16 risk attributes, and 3 risk constructs. The survey, divided into four parts, was administered to 508 residents of Santiago, Chile. Using factor analysis, three main factors, which accounted for 80% of the sample's variance, were identified: factor 1, commonly called "Dread Risk" in the literature, explained 37% of variance; factor 2, "Unknown Risk," explained 28%; and factor 3, which we called "Personal Effect," explained 15% of the variance. On average, individuals perceived themselves as less exposed to risk and with more control and knowledge about them than the general population. OLS regression models were used to test the association of perceived risk with the three main factors. For social risk, factor 1 had the greatest explanatory power, while factor 2 had a negative sign. For personal risk, only factors 2 and 3 were significant, with factor 3 having the greatest explanatory power. Risk denial (defined as the difference between perceived personal and social risk) was associated with factors 1 and 2 only, with factor 2 having a negative sign. The difference between desired and actual regulation levels proved positive for all hazards, thus indicating that Chileans are dissatisfied with the current regulation level for all the hazards analyzed. The comparison of data at the aggregate and at the individual subject's level suggests that while the aggregate analysis overestimates the magnitude of the correlations it still reflects the tendency of the individual responses.  相似文献   
954.
Three topics are addressed: (1) measurement issues (e.g., the reliability and validity of neurobehavioral test scores), (2) general principles of assessment, including test selection, and (3) interpretation of scores. Psychological tests generally perform as well as medical tests in terms of reliability and validity. Test manuals, assessment textbooks, and psychologists are useful resources to the risk assessor. The variety of different tests employed in neurobehavioral studies complicates interstudy comparisons. In addition, tests that ostensibly assess the same general domain of function might assess somewhat different abilities within that domain. Although a uniform battery for use in all studies seems desirable, the battery appropriate for a specific study depends on study goals, knowledge about the mechanism(s) of neurotoxicity, nature of the study population, and pattern of exposure. Exposure-related neurobehavioral deficits are generally indicators of "altered function" rather than of "clinical disease." Limiting concern to end points corresponding to clinical disease might not be appropriate. Many neurobehavioral diagnoses are phenomenological and a neurotoxicant might cause a unique pattern of deficits for which no label has been created. The concern that a small shift in the central tendency of a distribution of test scores has no significance for the individual should be reexamined in light of the prevention paradox, formulated on the basis of epidemiologic studies of chronic disease. Poor performance on a neurobehavioral test does not necessarily map clearly onto underlying behavioral or neural substrate. The absence of such linkages, given current knowledge about brain-behavior relationships, should not reduce confidence in neurobehavioral end points. Use of neurobehavioral test scores involves considerations that differ little from those that the risk assessor routinely addresses in using end points commonly used in research on other topics in environmental epidemiology.  相似文献   
955.
956.
Following the herd is easy when it comes to business ventures. But if you really want to start something new, you must first carefully think it through. Learn some ways to do that before you set out on a new path.  相似文献   
957.
This paper investigates whether children later reported as having been unwanted or mistimed at conception will, when compared with children reported as wanted, show adverse effects when the following criteria are applied: receipt of antenatal care before the sixth month of gestation, supervised delivery, full vaccination of the child, and child growth (stunting). The study uses data from five recent Demographic and Health Survey enquiries in Bolivia, Egypt, Kenya, Peru, and the Philippines. In Peru, children unwanted at conception were found to have significantly worse outcomes than other children, but in the other countries, a systematic effect was found only for receipt of antenatal care. Weak measurement of the complex concept of wantedness may have contributed to these results. Birth order of the child, with which wantedness is inextricably linked, has more powerful and pervasive effects, with first-born and second-born children being much less likely to show adverse effects.  相似文献   
958.
In September 2000, the Community Members Against Discrimination (CMAD), a grassroots LGBT organization in DeKalb, Illinois, convinced their city council to add protection against discrimination on the basis of gender identity and expression. Written as an autoethnography, this essay considers the events of the campaign in terms of queer theory and the study of public argument by isolating a set of episodes that bring the reader closer to the experiences of transgender citizens who act in a public culture. The author also explores his own responsibilities as a scholar of communication, an activist, and a member of the LGBT community.  相似文献   
959.
In 1896, Krafft-Ebing published Psychopathia Sexualis. Popularly defined as hereditary weakness or taintedness in the family pedigree, degeneracy was called upon as a causal explanation for perversions of the sexual instinct. Although Krafft-Ebing accepted Karl Ulrichs proposal that homosexuality could be innate and probably located in the brain, he paid little attention to neuropathological sexology. Alfred Binet challenged Krafft-Ebing's orthodoxy by explaining fetishism in terms of associative learning, to which Krafft-Ebing's response was that only those with a hereditary taint would be vulnerable. Thus did the venerable nature-nurture antithesis maintain its rhetoric, even to the present day. Krafft-Ebing died too soon to meet the Freudian challenge of endopsychic determinism, and too soon also to encounter the idea of a developmental multivariate outcome of what I have termed the lovemap. Like other brain maps, for example the languagemap, the lovemap requires an intact human brain in which to develop. The personalized content of the lovemap has access to the brain by way of the special senses.  相似文献   
960.
Interest in change interventions that are common to different models of relationship therapy has spurred investigation of enactments as one such candidate. In change-focused enactments, therapists structure and coach couple/family interaction, as opposed to channeling interaction through the therapist. Still, varying levels of couple/family distress, volatility, and reactivity mean that readiness for enactment intervention varies along a broad continuum and changes over the course of therapy. This suggests the need for differentiated enactments. Currently, however, no model exists for adapting enactments to changing relationship conditions. We propose a five-stage developmental model of clinical operations in couple therapy that adapts the process and structure of enactments to changing levels of relationship distress, interactional volatility, and emotional reactivity. The model increases the possibility for therapists to use enactments successfully over the entire course of couple therapy. Issues to be considered in using the couple enactments model as a template for the development of enactment models for other relationship systems are noted.  相似文献   
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