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921.
922.
Liss MB 《Ethics & behavior》1994,4(2):133-146
During the past 20 years, states have increasingly expanded the lists of individuals who are obligated to report their suspicions of child abuse and neglect. These legal requirements are juxtaposed with ethical considerations in research and professional practice. The ethical issues include the obligation to maintain both confidentiality of information provided by human participants and the safety and protection of these participants. This article reviews the types of state child abuse reporting statutes and outlines the categories of mandated reporters. I develop a model of how individual researchers should approach deciding whether they are mandated reporters of child abuse and neglect. 相似文献
923.
This paper addresses a problem in reporting scientific research. The problem is how to distinguish between justifiable and unjustifiable data selection. Robert Millikan is notorious for an infamous remark that he used all his data when in fact he had used a selection. On this basis he has been accused of fraud. There is a tension here — historians and his defenders see his selection as understandable and legitimate, while current statements about the Responsible Conduct of Research imply his selection was illegitimate. This paper discusses two main issues that arise in assessing his conduct, whether he was intentionally misleading and whether he actually did mislead the scientific community about some facts of nature. It is argued that he was not intentionally misleading, and that it is unlikely that he misled the scientific community. 相似文献
924.
925.
Cognitive function after open-heart surgery: Are postoperative neuropsychological deficits caused by cardiopulmonary bypass? 总被引:3,自引:0,他引:3
Ralph H. B. Benedict 《Neuropsychology review》1994,4(3):223-255
Despite the many technological developments in arterial perfusion and cardiac surgical procedures, open-heart surgery is still believed to pose a significant risk for cerebral injury. There are several potential causes of brain damage during open-heart surgery, including prolonged or severe arterial hypotension, as well as emboli emanating from the cardiopulmonary bypass circuit or the operative field. This article reviews the available neuropsychological studies of outcome following cardiac valve replacement and coronary artery bypass grafting. Because both procedures are life-saving operations, the research in this area has been quasi-experimental and fraught with methodological problems. Nonetheless, the findings converge to suggest that cognitive dysfunction occurs after open-heart surgery, and that the deficits are attributable, at least in part, to factors specific to the operation or to the patient being maintained on cardiopulmonary bypass. Preliminary findings suggest that embolization is the primary cause of perioperative deficits in uncomplicated operations. Studies have also consistently found preoperative deficits in this population, suggesting that neuropsychological dysfunction is caused by severe chronic cardiac disease as well as open-heart surgery. 相似文献
926.
Pizlo and Salack-Golyska (1994) have raised an important question about the validity of the interpretation of experiments reported by Lappin and Love (1992)—based on the fact that alternative cues in the image plane might have supported the shape discriminations in those experiments. The meaning of the hypothesis that visual space may be scaled by congruence under motion is clarified, pertinent evidence is reviewed, and new experimental evidence is reported We conclude that visual space can be metrically scaled by congruence of moving shapes. 相似文献
927.
Jeffrey T. Andre Richard A. Tyrrell Herschel W. Leibowitz Mary E. Nicholson Minqi Wang 《Attention, perception & psychophysics》1994,56(3):261-267
Contrast sensitivity was measured for 12 healthy young males while sober, after ingestion of an alcohol placebo, and after ingestion of alcohol (95% grain alcohol; mean estimated blood alcohol level = .088%). Observations were made for both stationary gratings and gratings that traveled through a circular path and required pursuit eye movements. The significant alcohol-related reduction in contrast sensitivity was 2.6 times greater for moving (.29-log-unit reduction) than for stationary gratings (.11-log-unit reduction). The loss in contrast sensitivity for the moving gratings of high spatial frequency (12 cpd) was particularly severe (.37 log unit). Estimated blood alcohol level was correlated with the loss in contrast sensitivity for moving gratings (r = .61), but not with the loss for stationary gratings. Estimated blood alcohol level was strongly correlated with the difference between the loss in contrast sensitivity to moving and stationary gratings (r = .75). These results are consistent with reports that alcohol consumption degrades the ability to make pursuit eye movements. Subjects’ perceived intoxication level was not a reliable predictor of any index of visual performance. 相似文献
928.
Richard L. Doty Richard Smith Donald A. Mckeown Jaya Raj 《Attention, perception & psychophysics》1994,56(6):701-707
It is not known whether nominally different olfactory tests actually measure dissimilar perceptual attributes. In this study, we administered nine olfactory tests, including tests of odor identification, discrimination, detection, memory, and suprathreshold intensity and pleasantness perception, to 97 healthy subjects. Aprincipal components analysis performed on the intercorrelation matrix revealed four meaningful components. The first was comprised of strong primary loadings from most of the olfactory test measures, whereas the second was comprised of primary loadings from intensity ratings given to a set of suprathreshold odorant concentrations. The third and fourth components had primary loadings that reflected, respectively, mean suprathreshold pleasantness ratings and a response bias measure derived from a yes/no odor identification signal detection task. In an effort to adjust for potential confounding influences of age, gender, smoking, and years of schooling on the component structure, a matrix of residuals from a multiple regression analysis, which included these variables, was also analyzed. A similar component pattern emerged. Overall, these findings suggest, in healthy subjects spanning a wide age range, that (1) a number of nominally distinct tests of olfactory function are measuring a common source of variance, and (2) some suprathreshold odor intensity and pleasantness rating tests may be measuring sources of variance different from this common source. 相似文献
929.
Frank B. Baker 《Psychometrika》1965,30(2):165-178
The sampling properties of four item discrimination indices (biserialr, Cook's indexB, theU–L 27 per cent index, and DeltaP) were investigated in order to ascertain their sampling properties when small samples drawn from actual test data rather than constructed data were employed. The empirical results indicated that the mean index values approximated the population values and that values of the standard deviations computed from large sample formulas were good approximations to the standard deviations of the observed distributions based on samples of size 120 or less. Goodness of fit tests comparing the observed distributions with the corresponding distribution of the product-moment correlation coefficient based upon a bivariate normal population indicated that this correlational model was inappropriate for the data. The lack of adequate mathematical models for the sampling distributions of item discrimination indices suggests that one should avoid indices whose only real reason for existence was the simplification of computational procedures.This research reported herein was performed pursuant to a contract (OE-2-10-071) with the United States Office of Education, Department of Health, Education and Welfare. 相似文献
930.