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901.
When may a physician legitimately offer enrollment in a randomized clinical trial (RCT) to her patient? Two answers to this question have had a profound impact on the research ethics literature. Equipoise, as originated by Charles Fried, which we term Fried's equipoise (FE), stipulates that a physician may offer trial enrollment to her patient only when the physician is genuinely uncertain as to the preferred treatment. Clinical equipoise (CE), originated by Benjamin Freedman, requires that there exist a state of honest, professional disagreement in the community of expert practitioners as to the preferred treatment. FE and CE are widely understood as competing concepts. We argue that FE and CE offer separable and, in themselves, incomplete justifications for the conduct of clinical trials. FE articulates conditions under which the fiduciary duties of physician to patient may be upheld in the conduct of research. CE sets out a standard for the social approval of research by institutional review boards. Viewed this way, FE and CE are not necessarily competing notions, but rather address complementary moral concerns. 相似文献
902.
In response to the preceding commentary by Jerry Menikoff in this issue of the Journal, the authors argue that Fried's central concern is not that randomized clinical trials (RCTs) are conducted without consent, but rather that various aspects of the design and conduct of RCTs are in tension with physicians' duties of personal care to their patients. Although Fried does argue that the existence of equipoise cannot justify failure to obtain consent from research subjects, informed consent by itself does not supplant ill subjects' rights to personalized judgment and care embodied in Fried's equipoise. 相似文献
903.
A questionnaire constructed to assess epistemic curiosity (EC) and perceptual curiosity (PC) curiosity was administered to 739 undergraduates (546 women, 193 men) ranging in age from 18 to 65. The study participants also responded to the trait anxiety, anger, depression, and curiosity scales of the State-Trait Personality Inventory (STPI; Spielberger et al., 1979) and selected subscales of the Sensation Seeking (SSS; Zuckerman, Kolin, Price, & Zoob, 1964) and Novelty Experiencing (NES; Pearson, 1970) scales. Factor analyses of the curiosity items with oblique rotation identified EC and PC factors with clear simple structure. Subsequent analyses of the EC items provided the basis for developing an EC scale, with Diversive and Specific Curiosity subscales. Moderately high correlations of the EC scale and subscales with other measures of curiosity provided strong evidence of convergent validity. Divergent validity was demonstrated by minimal correlations with trait anxiety and the sensation-seeking measures, and essentially zero correlations with the STPI trait anger and depression scales. Male participants had significantly higher scores on the EC scale and the NES External Cognition subscale (effect sizes of r =.16 and.21, respectively), indicating that they were more interested than female participants in solving problems and discovering how things work. Male participants also scored significantly higher than female participants on the SSS Thrill-and-Adventure and NES External Sensation subscales (r =.14 and.22, respectively), suggesting that they were more likely to engage in sensation-seeking activities. 相似文献
904.
Common factor aging theories state that correlations among cognitive age effects signify a single underlying causal process. The logic underlying this proposition was evaluated by examining correlated cognitive change in a sample of 391 initially nondemented older adults who were tested annually for up to 16 years. Between-person correlations among rates of change (range = .56-.61) were partly attributable to model misspecification and the aggregation of heterogeneous groups of individuals. Correlated within-person cognitive change was much stronger in the cases (.45-.51) than in the noncases (.07-.18). These results demonstrate that correlated change may either signify causal commonality or the cumulative effects of multiple age-related conditions that can affect multiple cognitive systems. 相似文献
905.
Berlin CI Hood L Morlet T Rose K Brashears S 《Mental retardation and developmental disabilities research reviews》2003,9(4):225-231
Auditory brainstem responses (ABRs) and otoacoustic emissions (OAEs) are objective measures of auditory function, but are not hearing tests. Normal OAEs reflect normal cochlear outer hair cell function, and an ABR indicates a synchronous neural response. It is quite possible for a patient to have normal OAEs but absent or grossly abnormal ABR and a behavioral audiogram that is inconsistent with either test. These patients, who may constitute as much as 10% of the diagnosed deaf population, have auditory neuropathy/dys-synchrony (AN/AD). To diagnose AN/AD accurately, ABRs are obtained in response to condensation and rarefaction clicks to distinguish cochlear microphonics (CM) from neural responses. Appropriate management is confounded by variation among patients and changes in auditory function in some patients over time. Recommendations for management include visual language exposure through methods such as American Sign Language (ASL), Cued Speech, or baby signs, and closely following patients. 相似文献
906.
A sample of 149 university students completed the Francis Psychological Type Scales together with the Francis Scale of Attitude Toward Christianity. The data indicated that university students classified as Feeling Types hold a more positive attitude toward Christianity than those classified as Thinking Types. These findings replicate the 1999 report of Jones and Francis. 相似文献
907.
Searching night and day: a dissociation of effects of circadian phase and time awake on visual selective attention and vigilance 总被引:1,自引:0,他引:1
How does sleepiness affect selective attention? We studied the effect of circadian phase and time awake on visual search. The generalized-cognitive-slowing hypothesis predicts that search rate will be slower, feature guidance less effective, and response time (RT) lengthened when observers are sleepy. Observers performed spatial-configuration (finding a 5 among 2s) and conjunction (finding red vertical among red horizontal and green vertical) search tasks during 38 hr of wakefulness under constant conditions. Adverse circadian phases and elapsed time awake did lead to increased RT (corrected for errors). However, contrary to the hypothesis, search rates (indexed by RT x Set Size slopes) were constant across the protocol. This was true for conjunction as well as for spatial-configuration search, indicating that feature guidance was also insensitive to sleepiness. The locus of sleepiness effects on search is probably downstream from the bottleneck of attentional selection. Observers did trade accuracy for speed when sleepy. This implicates decision-stage impairments. 相似文献
908.
In auditory research, it is often desirable to present more than two auditory stimuli at any one time. Although the technology has been available for some time, the majority of researchers have not utilized it. This article provides a simple means of presenting multiple, concurrent, independent auditory events, using two or more different sound cards installed within a single computer. By enabling the presentation of more auditory events, we can hope to gain a better understanding of the cognitive and attentional processes operating under more complex and realistic scenes, such as that embodied by thecocktail party effect. The software requirements are Windows 98SR2/Me/NT4/2000/XP, Visual Basic 6.0, and DirectX 7.0 or above. The hardware requirements are a Pentium II, 128 MB RAM, and two or more different sound cards. 相似文献
909.
Charles C. Benight Erika Swift Jean Sanger Anne Smith Dan Zeppelin 《Journal of applied social psychology》1999,29(12):2443-2464
Social-cognitive theory and conservation-of-resources theory were utilized to understand individual differences in psychological response to natural disaster. Coping self-efficacy, lost resources, social support, and optimism were assessed along with demographic variables in predicting distress following Hurricane Opal. Participants included 67 residents of Okaloosa County, Florida. Multiple regression analyses indicated that coping self-efficacy was the strongest predictor of general distress and trauma-related distress. Loss of resources and gender were also important predictors of general distress. Path analyses demonstrated that lost resources directly influenced general distress, social support, optimism, and coping self-efficacy. These analyses also indicated that coping self-efficacy perceptions mediated the relationships between loss of resources and trauma-related distress, social support and both trauma and general distress, and optimism and both types of distress. Theoretical implications are discussed. 相似文献
910.
A thought that we all entertain at some time or other is that the course of our lives might have been very different from
the way they in fact have been, with the consequence that we might have been rather different sorts of persons than we actually
are. A less common, but prima facie intelligible thought is that we might never have existed at all, though someone rather
like us did. Arguably, any plausible theory of personal identity should be able to accommodate both possibilities. Certain
currently popular Reductionist theories of personal identity, however, seem to be deficient in precisely this respect. This
paper explores some Reductionist responses to that challenge.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献