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991.
The present study assessed drug use and the validity of self–reports of substance use among help–seeking veterans referred to a specialty clinic for the assessment of posttraumatic stress disorder (PTSD). Patients (n?=?341) were asked to provide a urine sample for use in drug screening as part of an evaluation of PTSD. Self–reports of substance use were compared with same–day supervised urine samples for 317 patients who volunteered to participate in a drug screening. Results suggested that self–reports were generally quite valid. Only 8% of the cases involved patients not reporting substance use detected by urine screens. A total of 42% of the participants were identified as using drugs of abuse (excluding alcohol) through self–report and urine drug screens. Among participants using drugs, PTSD diagnosis was significantly associated with greater marijuana and depressant use as compared with stimulant (cocaine and amphetamines) use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
Changes in projects are common and may be deleterious or beneficial—whether you see a change as a conflict or a valuable lesson depends only on your prospective. Project changes affect the cost, the scheduling, and the duration of projects, both directly and indirectly. Despite many articles and much discussion in practice and academic literature, there is a lack of information about systematic approaches to manage project change. This paper introduces a comprehensive project change management system that is founded on five principles: (1) promote a balanced change culture; (2) recognize change; (3) evaluate change; (4) implement change; and (5) continuously improve from lessons learned. By applying this project change management system, project participants can minimize deleterious change and promote beneficial change.  相似文献   
993.
Observational assessments were made of 51 preschoolers' (mean age?=?53.25 months) peer aggression and emotional displays outside of (baseline) and during aggressive interactions, and their emotion knowledge and peer acceptance were also assessed. Results indicated that the connections between children's affective dispositions and their aggression and peer acceptance varied as a function of both the emotion context (baseline vs. aggression related) and the particular emotion involved (happiness vs anger). Emotion knowledge and affective dispositions overlapped little with each other, and both made independent contributions to peer acceptance and aggression. Mediation analyses revealed, however, that the significant connections between children's emotional dispositions and knowledge and their peer acceptance were mostly mediated by aggression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
994.
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996.
Responds to C. A. Heflinger's (1987) critique of the present authors (1986) by reiterating their concern for the principle of autonomy. The present authors note that all patients were fully informed about the research plan and their right to withdraw. Nonetheless, the ethical criticism offered by Heflinger regarding randomization cannot be entirely dismissed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
Abstract The existing literature contains strong evidence that characteristics of buildings and indoor environments significantly influence rates of respiratory disease, allergy and asthma symptoms, sick building symptoms, and worker performance. Theoretical considerations, and limited empirical data, suggest that existing technologies and procedures can improve indoor environments in a manner that significantly increases health and productivity. At present, we can develop only crude estimates of the magnitude of productivity gains that may be obtained by providing better indoor environments; however, the projected gains are very large. For the U.S., we estimate potential annual savings and productivity gains of $6 billion to $19 billion from reduced respiratory disease; $1 billion to $4 billion from reduced allergies and asthma, $10 billion to $20 billion from reduced sick building syndrome symptoms, and $12 billion to $125 billion from direct improvements in worker performance that are unrelated to health. Sample calculations indicate that the potential financial benefits of improving indoor environments exceed costs by a factor of 18 to 47. The policy implications of the findings are discussed and include a recommendation for additional research.  相似文献   
998.
To test the hypothesis that memory-based ratings should be less accurate than ratings collected under conditions that minimize demands on memory, data were obtained from 82 undergraduates who had rated 4 videotapes of graduate student lecturers. Half of the tapes were rated immediately after they were viewed; Ss returned the following day and rated the remaining tapes from memory. Memory-based behavior ratings and performance evaluations showed higher intercorrelations (more halo) than did ratings that were collected immediately after viewing the ratee's performance. However, ratings were systematically more accurate in the delayed-rating condition than in the immediate-rating condition. It is argued that (1) under certain conditions, raters may depend on their general impressions of ratees rather than on their memory for specific details; and (2) these schematic evaluations may preserve a greater proportion of valid information, as compared with irrelevant detail, than is available immediately after observing ratee behavior. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Compared initial and 3-yr follow-up peer ratings of 19 boys, who were in Grades 1–3 at the beginning of the study, who had attention deficit disorder with hyperactivity (ADDH). When the entire group was considered, nominations on the Aggression and Likability factors of a pupil evaluation inventory improved. Subgroups were created using teacher ratings on an aggression scale. Peer ratings of Aggression improved for Ss whom teachers rated below the median on the aggression scale but not for Ss rated above the median. Subgroups reflecting other teacher and peer ratings were less effective in predicting differential change in peer ratings of ADDH Ss. (8 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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