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831.
The multiple uses of performance appraisal (PA) have been the focus of much research, often yielding conflicting findings and conclusions. This study used an untreated control group design to examine the effects of separating the developmental and evaluative PA uses (in time and by person) on employee attitudes and behavioral intentions. Results indicated no effect on employee attitudes, however, employees in the separated PA group reported they were less likely to use development in the future.  相似文献   
832.
Teacher preparation programs are under scrutiny for their role in the troubled American educational system. If American education is to improve, teacher educators must identify and encourage teachers to use effective teaching practices. A promising technique for increasing use of teaching practices is providing feedback to teachers on newly acquired behaviors. The focus of this study was to examine the effects of immediate corrective feedback on one specific teaching behavior, use of three-term contingencies, to preservice teachers. A multiple baseline design across participants was used to evaluate the effects of immediate corrective feedback, delivered via a wireless FM listening system. Immediate corrective feedback (as compared with delayed feedback) was shown to be an effective way to increase preservice teacher completion of three-term contingency trials by all participants. These findings and other considerations for additional research using feedback are addressed.  相似文献   
833.
This review describes the discrepancy in findings between postoperative cognitive performance and postoperative cognitive complaints long time after an operation under general anesthesia. Shortly (from 6 hr to 1 week) after an operation a decline in cognitive performance is reported in most studies. However, long time (from 3 weeks to 1–2 years) after an operation this is rarely found although some patients are still reporting cognitive complaints. In general this kind of research is suffering from severe methodological problems (use of insensitive tests, lack of control groups, lack of parallel tests, different definitions of cognitive decline). However, these problems cannot totally explain the discrepancy in findings in the long term. Thus, there are patients who have persistent cognitive complaints long time after an operation, that cannot be measured with cognitive tests. More psychological factors such as fixation on short-term cognitive dysfunction, mood, coping style, and personality are possible explanations for these cognitive complaints in the long term. As a consequence, these factors should be a topic in future research elucidating the persistence of these cognitive complaints long time after an operation under general anesthesia.  相似文献   
834.
Part of the National Placebo Initiative in Canada included public consultations, based on the belief that the views of the public should inform Canadian policy development on what constitutes appropriate placebo use. Public consultations took place nationally in 2003. A deliberative dialogue approach was used, or a structured discussion format designed to facilitate the consideration of complex issues and build consensus. The placebo debate was characterized as having 3 distinct approaches and each were explored. The first approach “Maximize Patient Protection” identified the need for experts to determine appropriate placebo use and that placebos should only be allowed under very restricted conditions. The second approach “Maximize Medical Knowledge” identified that placebos give essential information about the safety and efficacy of new drugs, and are appropriate when the rights, safety and well-being of research participants are ensured. The third approach “Maximize Patient Autonomy” identified that the current system of regulating placebo use is paternalistic and that patients should be able to define what is in their best interests and have more leeway to determine for themselves if they wish to participate in a placebo-controlled trial. Advantages and disadvantages of each approach were considered and feedback on what constitutes appropriate placebo use was sought. The major findings were that: PCTs were considered a valuable and acceptable part of advancing medical knowledge; research using placebos must be valid and justifiable; a patient-centred approach needs to be fostered; patient autonomy (choice) should be a first consideration and take clear precedence in trials of low to medium risk; patient protection (or health) may need to “trump” patient autonomy at higher levels of risk and/or patient vulnerability; placebos are not a violation of the duty of care as duty of care is best met by identifying a choice for patients, whenever a choice is available. These consultations clearly were not designed to produce conclusive evidence, but rather to provide some useful insights into what the public may think about placebo use; additional studies are indicated. Funding for the public consultations was provided by Health Canada and the Canadian Institutes of Health Research. An earlier version of this paper was presented at an international conference, “Placebo: Its Action and Place in Health Research Today,” held in Warsaw, Poland on 12–13 April, 2003.  相似文献   
835.
The UK Medical Research Council, in order to further its mission of maintaining and improving human health, supports a substantial number of clinical trials on a wide variety of medical questions; some of these trials involve the use of placebos as controls or to maintain blinding. Before providing support, proposed trials are carefully reviewed to assess scientific quality, and to determine whether a placebo is required and is ethical — in addition to ethics review by independent Research Ethics Committees. Some questions such as the choice of placebos in trials in developing countries, in surgical trials and those involving alternative medicine require consideration of additional, specific issues. Involvement of consumers in MRC work has been increasing and includes the establishment of a Consumer Liaison Group; members of this group comment on patient information leaflets for clinical trials, helping to improve patient understanding of trials and ensuring topics like placebo use are explained clearly. Views differ on the value of placebos in clinical care and on their mechanism of action; continuing research is helping to clarify the issues. An earlier version of this paper was presented at an international conference, “Placebo: Its Action and Place in Health Research Today,” held in Warsaw, Poland on 12–13 April, 2003.  相似文献   
836.
The model of a single central bottleneck for human information processing is critically examined. Most evidence cited in support of the model has been observed within the overlapping tasks paradigm. It is shown here that most findings obtained within that paradigm and that were used to support the model are also consistent with a simple resource model. The most prominent findings are the millisecond-for-millisecond slope at the left of the RT2-SOA curve, the high RT1-RT2 correlation, the additivity of the effects on RT2 of SOA and of the difficulty of selecting R2, and the washout of the effect of S2 discriminability on RT2 in a dual-task condition. In addition, the asymmetry of the effects of the dual-task requirement on RT1 and RT2 can be accounted for by the resource model provided that it assumes uneven allocation of resources, which is quite reasonable in view of the task asymmetry inherent in the demand characteristics of the paradigm. The same is true for two other findings that appear to support the single-bottleneck model-that in the dual-task condition, the demand of the first task affects equally RT1 and RT2 and that its effect on RT1 is the same as the corresponding effect in the single-task condition. Furthermore, the single-bottleneck model is hard to reconcile with a negative slope at the left of the RT1-SOA curve or a positive slope at the left of the IRI-SOA curve, unless augmented by ancillary assumptions that are yet to be substantiated. Representative data were fit by each of the models using its optimal set of parameters. Both models achieved quite good degrees of fit. It is further argued that since the overlapping tasks paradigm is heavily biased in favor of a speedy reaction to the stimulus that appears first, it is nonoptimal for testing the central bottleneck model. Finally, the bottleneck model is examined in terms of other scientific criteria.  相似文献   
837.
Well-conducted prevention and intervention research has the potential to serve the dual ends of enhancing children's adaptive outcomes and elucidating important developmental processes and mechanisms related to change. Admirably, the Fast Track preventive intervention was conceived in accord with explicit developmental theory related to the development of conduct problems. Herein, I consider how the present reports of grade-3 outcomes allow examination of causal processes and developmental mechanisms related to the effects uncovered, featuring the constructs of prediction, moderation, and particularly mediation. The multifaceted, intensive nature of the Fast Track preventive intervention is at once a clinical strength and a liability in terms of isolating causal processes underlying child change. I also consider issues related to the random assignment of the investigation and to policies that may emerge from the findings. In all, research that aims to identify relevant developmental and causal processes must incorporate both experimental and nonexperimental paradigms that are conceptualized from the outset with explanatory purposes in mind.  相似文献   
838.
This study allowed subjects to audit each other's responding during a series of competitive contests. Six pairs of female college students competed in 3-min contests in which the competitive response was a knob pull. A sum of money was divided using a proportional distribution or a 100%/0% reward distribution. In the proportional distribution, a subject's proportion of the sum was her proportion of the total number of responses. Also, in every contest either subject could make a response that would end the contest prematurely and give both subjects the same amount: a sum equal to 33% of the competitive total. Each subject could press either or both of two audit buttons that displayed her own and the other's response total for 10 s. Results replicated earlier findings in showing the superiority of the proportional distribution in total number of competitive responses made. No subject audited continuously, and only 1 audited most of the time. Most audits were interpersonal, including both own and other's scores. Auditing typically was more frequent in 100%/0% contests in which subjects were more likely to stop the contest when they were far behind. Winners were more likely to audit than were losers. Competitive response rates increased when the differences revealed by audits were small and decreased when they were large. Overall audit patterns were consistent with the view that feedback as "news" is more often sought when it can lead to improved outcomes.  相似文献   
839.
Guided by the Sport-Confidence Model, this study examined the associations among a positive body image, sport-confidence, and sport performance evaluations. Using a cross-sectional design, a purposive sample of 314 Jamaican athletes (male = 70.7%; Mage = 22.85; SD = 4.89) completed measures of body and functionality appreciation, sport-confidence, and subjective sport performance. Results from path analysis provided evidence for good model-data fit. Body (B = 9.03, p < .001) and functionality (B = 4.93, p = .036) appreciation exerted direct effects on sport-confidence. Sport-confidence exerted a direct effect on sport performance evaluations (B = 0.09, p < .001). Body (B = 0.79, CI95% [0.44, 1.17]) and functionality (B = 0.43, CI95% [0.05, 0.92]) appreciation exerted indirect effects on sport performance evaluations through sport-confidence. Results indicate that supporting the development of a positive body image in athletes may contribute to feelings of sport-confidence and positive performance outcomes.  相似文献   
840.
One of the arguments against conducting human subject trials inthe Third World adopts a distributive justice principle found ina commentary of the CIOM'S Eighth Guideline for internationalresearch on human subjects. Critics argue that non-participantmembers of the community in which the trials are conducted areexploited because sponsoring agencies do not ensure that theproducts developed have been made reasonably available to theseindividuals.I argue that the distributive principle's wording is too vagueand ambiguous to be used to criticize any trial. Furthermore,the mere fact that an experiment does not fulfill this particulardistributive justice principle does not entail that it isunethical.  相似文献   
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