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941.
It is very common to find meta-analyses in which some of the studies compare 2 groups on continuous dependent variables and others compare groups on dichotomized variables. Integrating all of them in a meta-analysis requires an effect-size index in the same metric that can be applied to both types of outcomes. In this article, the performance in terms of bias and sampling variance of 7 different effect-size indices for estimating the population standardized mean difference from a 2 x 2 table is examined by Monte Carlo simulation, assuming normal and nonnormal distributions. The results show good performance for 2 indices, one based on the probit transformation and the other based on the logistic distribution. 相似文献
942.
Variations in the state of momentary emotions of Brazilian hospital nurses on day and night shifts were recorded. Ten graduate nurses working on day and night shifts in the clinical ward of hospitals completed the Present Mood States List of Engelmann at the beginning and end of the first and last days of each shift. Analysis indicated (a) nurses had a stable emotional profile, present at the working shift, and (b) variations in present mood states related to specific effects of shift work were observed when comparisons were made between the present mood states at the beginning and end of each shift duty. 相似文献
943.
The study explored the association between the perceptions 175 Chilean business students held about their parents' acceptance of academic dishonesty and their self-reports of academic dishonesty. Regressing scores for parental acceptance onto self-reported academic dishonesty indicated it accounted for a small (2.2%) but significant amount of variance beyond demographic and academic performance variables. Effect size analysis based on structure coefficients indicated that parental acceptance was the second best predictor in the equation, suggesting that parental acceptance is a correlate that merits further study. 相似文献
944.
945.
Gábor?Jandó Tiziano?AgostiniEmail author Alessandra?Galmonte Nicola?Bruno 《Behavior research methods》2003,35(1):70-81
Surface color is traditionally measured by matching methods. However, in some conditions, the color of certain surfaces cannot be measured: The surface simply looks brighter or darker than all the patches on a matching scale. We studied the reliability, validity, and range of application of three different types of simulated Munsell scales (white-, black-, and split-surrounded) as methods for measuring surface colors in simple disk-ring displays. All the scales were equally reliable for matching both increments and decrements, but about 20% of the increments were unmatchable on the white-surrounded scale, about 13% of the decrements were unmatchable on the black-surrounded scale, and about 9% of the increments were unmatchable on the split-surrounded scale. However, matches on all the scales were linearly related. Therefore, it is possible to convert them to common units, using regression parameters. These units provide an extended metric for measuring all increments and decrements in the stimulus space, effectively removing ceiling and floor effects, and providing measures even for surfaces that were perceived as out of range on some of the scales. 相似文献
946.
Baamonde C Lumbreras MA Martínez-Cué C Vallina IF García-Calatayud S Flórez J Dierssen M 《Stress (Amsterdam, Netherlands)》1999,3(2):147-162
Neonatal handling is known to induce long-lasting changes in behavioral and neuroendocrine responses to stress. Since the central noradrenergic system participates in the adaptive responses to stressful conditions we have analyzed the effects of postnatal handling on beta-adrenoceptor binding sites and isoprenaline- and forskolin-stimulated cyclic AMP accumulation in cerebral cortex, hippocampus and cerebellum of rats at 1 and 3 months of age. Handled animals showed reduced emotional reactivity and lower ACTH and corticosterone secretion after stress. Binding studies using [(3) H]CGP12-177 revealed increased beta-adrenoceptor binding sites in handled rats in cerebellum and cerebral cortex with no changes in hippocampus, and decreased affinity in all cerebral regions. Handling reduced basal levels of cyclic AMP in hippocampus and cerebellum but not in cerebral cortex. The concentration-response curves of cyclic AMP to isoprenaline were displaced to the right in cerebellum of handled rats without differences in Emax; however, Emax was significantly reduced in cerebral cortex and hippocampus. Direct stimulation of the catalytic subunit of adenylyl cyclase by forskolin reduced the efficiency in hippocampus and cerebellum, but not in cerebral cortex of handled animals. It is concluded that neonatal handling reduces the binding properties of beta-adrenoceptor and its primary biochemical responses in the young rat brain, which may account for the reduced responsiveness to stress attained in the handled rats, and may explain the persistence of the effect. The present study emphasizes the role of the central noradrenergic system in modulating the behavioral and neurendocrine responses to neonatal handling. 相似文献
947.
Permanent and transient effects of repeated preweaning stress on social and sexual behaviors of rats
González Jatuff AS Berástegui M Rodríguez CI Rodríguez Echandía EL 《Stress (Amsterdam, Netherlands)》1999,3(2):97-106
We have reported that exposure of preweaning male and female rats to a model of unpredictable mild physical stressors (Neo-A) can decrease the behavioral and hormonal responses to acute and chronic stress as adults. In this paper we have analyzed the effect of Neo-A on development of social behaviors, including aggressiveness, social dominance, and sexual behavior in adulthood. The subjects were divided into two groups: Neo-A (daily exposed to unpredictable mild stresses- from day 2 up to day 15 of suckling; n = 30 litters) and controls (C) (undisturbed rats, except for testing, during the same period of life; n = 26 litters). When day 6 pups were submitted to a social clustering test the Neo-A group showed a higher rate of litter-mate clustering than C. The 35 days Neo-A males and Neo-A females submitted to a social behavior test after 24 h of social isolation also showed higher scores of time spent in active social interaction than controls, as well as a higher ratio of animals showing aggressive playing. A second social behavior test performed after 48 h of social isolation at days 75-80 of age revealed that only Neo-A females displayed increased social behavior and aggressive behaviors, whereas controls did not. A water competition test performed at 24 and 48 h after water deprivation showed that Neo-A adult males spent more time in possession of the drinking device and drank more frequently than C. When adult proestrous females were exposed to a sexual behavior test, the Neo-A group showed shorter latency and higher scores of lordosis quotient. These results support the view that exposure to this model of repeated mild stress early in life stimulates the development of social behavior, dominance and sexual behavior. 相似文献
948.
J. Olivares L. J. García-López M. D. Hidalgo S. M. Turner D. C. Beidel 《Journal of psychopathology and behavioral assessment》1999,21(1):67-78
The objective of this study is to examine the factor structure and psychometric properties of the SPAI in a sample of adolescent Spaniards. The results obtained support the use of the correlated two-factor SPAI subscales and indicate high coefficient alpha values for the SPAI subscales. The results provide support for the use of the SPAI in an adolescent population in a non-English-speaking country. Both exploratory and confirmatory factor analyses of the Social Phobia subscale showed a four-factor structure, instead of a five-factor dimension, as suggested by previous studies. Effects for gender and age and gender interaction were found. Limitations and suggestions for future research are discussed. 相似文献
949.
950.
以初中生为被试,以社会技能为目标行为,对角色扮演测试进行研究,探讨其影响因素和外在效度。研究采用2×2×2三因素实验设计,通过现场测试、刺激控制和问卷调查相结合的实验方法,着重探讨了角色扮演情境内容、测试指导语、实验助手的交往方式三个因素对被试行为的影响,证明了角色扮演行为随情境操纵的变化而变化,并发现在采用个体化的测试情境、低水平要求的指导语及非结构化的交往方式的情况下,外在效度最高。另外,多元回归统计分析表明被试性别、已有水平等对角色扮演行为水平也有影响。 相似文献