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821.
What type of items, keyed positively or negatively, makes social-emotional skill or personality scales more valid? The present study examines the different criterion validities of true- and false-keyed items, before and after correction for acquiescence. The sample included 12,987 children and adolescents from 425 schools of the State of São Paulo Brazil (ages 11–18 attending grades 6–12). They answered a computerized 162-item questionnaire measuring 18 facets grouped into five broad domains of social-emotional skills, i.e.: Open-mindedness (O), Conscientious Self-Management (C), Engaging with others (E), Amity (A), and Negative-Emotion Regulation (N). All facet scales were fully balanced (3 true-keyed and 3 false-keyed items per facet). Criterion validity coefficients of scales composed of only true-keyed items versus only false-keyed items were compared. The criterion measure was a standardized achievement test of language and math ability. We found that coefficients were almost as twice as big for false-keyed items’ scales than for true-keyed items’ scales. After correcting for acquiescence coefficients became more similar. Acquiescence suppresses the criterion validity of unbalanced scales composed of true-keyed items. We conclude that balanced scales with pairs of true and false keyed items make a better scale in terms of internal structural and predictive validity.  相似文献   
822.
823.
This study was based on a sample of male high school students who completed National Longitudinal Adolescent Health Surveys in 1994, 1995, and 2001. We studied these students prospectively, comparing those who later died by suicide (= 21) with those who were still living (= 10,101). We employed chi‐square and analysis of variance tests for statistical significance between suicide decedents and living respondents. Results showed suicide decedents were more likely to have experienced the suicide loss of another family member, to have been expelled from school, to have engaged in more delinquent actions including fighting, and to have greater involvement with the criminal justice system. Although one might have expected suicide casualties to have exhibited a greater amount of suicidal thoughts, attempts, and higher incidences of suicidality among their friends, our analyses did not find that these factors were associated with actual suicides. Should these findings be replicated, this would point to a need to refine youth suicide risk assessments. Collecting life histories, as well as identifying patterns of delinquency and fighting, may serve as more potentially fruitful means for assessing genuine suicide risk than some traditional risk assessment methods.z  相似文献   
824.
825.
Introduction     
Gil C. Santos 《Axiomathes》2015,25(2):145-146
  相似文献   
826.
827.
ABSTRACT: In the United States, suicide has traditionally been considered a White elderly phenomenon. Suicide rates have been increasing for Nonwhites in recent years, but it is not clear how this may have affected the age distribution, particularly for specific Nonwhite groups. An investigation of official 1976 suicide statistics among minority elderly revealed that suicide rates are also highest among the old for Chinese-, Japanese- and Filipino-Americans. Among Blacks and Native Americans, however, suicide rates are extremely low for the aged. Explanations for these findings are suggested and the need for a long-term study is indicated.  相似文献   
828.
Abstract

Variable practice promotes a higher level of motor learning than constant practice. The glutamate receptors, n-methyl-d-aspartate (NMDA) and alfa-amino-3-hydroxy-5-methyl-4-isoxazolepropionic (AMPA), have been associated with the changes in motor cortex that occur throughout the process of motor learning. Considering that, it is possible that variable practice is more associated with the NMDA and AMPA receptors than constant practice. This study aimed ao investigating the association between the glutamate receptors, NMDA and AMPA, and constant and variable practice schedules. Seventy-eight male mice practiced the rotarod task in a constant or variable scheduling, in two consecutive days (acquisition phase). Learning tests were performed 24?h and 10?days after the end of the acquisition phase. Variable practice was more associated with the NMDA receptor and had a greater AMPA receptor expression than constant practice. The results suggest that the benefits of variable practice are result of both the greater dependency on the NMDA receptor and the greater AMPA receptor expression.  相似文献   
829.
ABSTRACT: Suicide rates vary greatly by sex and race but the methods employed by these groups and changes in those methods have been studied neither closely nor systematically across time. In the present study annual official national statistics for specific methods of suicide by sex and racial group from 1923 to 1978 were examined. During this time period shifts were found among groups in the proportions of various suicide methods employed, most notably for women and Asian-Americans. Generally, firearm use increased among nearly all ethnic/racial-sex groups while the use of poisons declined. Although women continue to be more likely than men to kill themselves with solid and liquid poisons, in very recent years firearms have become a more common method. Among Japanese - and Chinese-Americans of both sexes the most frequently employed method has been hanging. Although this is still the case, the proportions have declined over time while the use of firearms has increased. Explanations are offered for the noted changes in method choice with particular attention being given to acculturation and changing societal roles.  相似文献   
830.
Ohne Zusammenfassung Bryn Mawr College Mit 2 Textabbildungen.  相似文献   
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