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31.
The purpose of this meta-analysis of randomized controlled trials was to evaluate the efficacy of psychological interventions for adults with noncancerous chronic low back pain (CLBP). The authors updated and expanded upon prior meta-analyses by using broad definitions of CLBP and psychological intervention, a broad data search strategy, and state-of-the-art data analysis techniques. All relevant controlled clinical trials meeting the inclusion criteria were identified primarily through a computer-aided literature search. Two independent reviewers screened abstracts and articles for inclusion criteria and extracted relevant data. Cohen's d effect sizes were calculated by using a random effects model. Outcomes included pain intensity, emotional functioning, physical functioning (pain interference or pain-specific disability, health-related quality of life), participant ratings of global improvement, health care utilization, health care provider visits, pain medications, and employment/disability compensation status. A total of 205 effect sizes from 22 studies were pooled in 34 analyses. Positive effects of psychological interventions, contrasted with various control groups, were noted for pain intensity, pain-related interference, health-related quality of life, and depression. Cognitive-behavioral and self-regulatory treatments were specifically found to be efficacious. Multidisciplinary approaches that included a psychological component, when compared with active control conditions, were also noted to have positive short-term effects on pain interference and positive long-term effects on return to work. The results demonstrated positive effects of psychological interventions for CLBP. The rigor of the methods used, as well as the results that reflect mild to moderate heterogeneity and minimal publication bias, suggest confidence in the conclusions of this review.  相似文献   
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The purpose of this study was to determine the effects of Type A behavior and family history of hypertension on cardiovascular reactivity to mental stress in a group of employed black women. Measures of heart rate and of systolic blood pressure (SBP) and diastolic blood pressure (DBP) were taken at rest, during a mental arithmetic task, and during the Type A Structured Interview (SI). Results indicated that the Type A behavior pattern was associated with SBP and DBP hyperresponsivity during the SI but not during mental arithmetic. Additionally, certain speech components of the Type A pattern, as well as features of the potential-for-hostility component, were also related to cardiovascular responses during the SI. Family history of hypertension did not influence the cardiovascular parameters either alone or in combination with Type A behavior. The results suggest that many of the cardiovascular response characteristics of the Type A pattern that have been observed in predominantly white samples also hold true for blacks. Replication of these findings with other subgroups of blacks, such as young females and middle-aged males, will help document the generality of these findings within the black population.  相似文献   
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Three experiments used a discriminated operant procedure to study conditional discrimination learning in rats. The first experiment showed that rats were capable of learning a biconditional discrimination in which two contexts served as conditional cues signalling the reinforcement contingencies associated with two discriminative stimuli. The discrimination was learned equally well when one discriminative stimulus signalled food, the other its absence, and when one stimulus signalled food, the other extinction plus mild footshock.

In Experiment 2 it was shown that prior training on such a conditional discrimination enhanced the subsequent context specificity of simple conditioning relative to control groups of animals for whom the prior training had not been conditional. Experiment 3 showed that a reversal of the significance of one pair of discriminative stimuli produced no spontaneous reversal in performance to a second, target, pair.

The pattern of results is best accounted for by an analysis of contextual conditional discrimination learning in terms of stimulus configurations and offers no support for the notion that rats may learn a general conditional rule or set.  相似文献   
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A comparison of two measures of egocentrism   总被引:1,自引:0,他引:1  
This study examined the relationship between two prominent measures of egocentrism, Enright's Adolescent Egocentrism Scale (AES) and Elkind's Imaginary Audience Scale (IAS), in a sample of 458 adolescents, between 10 and 15 years old. Both correlational and factor analyses indicated that the two measures assess distinctly different phenomena. As predicted, IAS scores were correlated with self-reported levels of shyness, nervousness, and social skills. These results provide partial evidence for the validity of the IAS as a measure of self-consciousness, though not necessarily egocentrism per se. The validity of the AES was not examined.  相似文献   
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An experiment was conducted to examine the effects of medical diagnostic-test results on illness appraisal and the recall of symptoms and behavior. Subjects were tested for a fictitious enzyme deficiency and were told either that the test result was positive (deficiency present) or that it was negative (deficiency absent). In addition, some of the subjects were told the test was accurate 95% of the time and others were told it was accurate 75% of the time. As predicted, subjects judged the enzyme deficiency as less serious and more prevalent when presented with positive test results. Subjects with positive test results also recalled more behaviors that had been labeled as risk factors. Although positive test subjects tended to report more deficiency-related symptoms, diagnosis did not affect the free recall of general symptoms. In addition, information concerning the reliability of the diagnostic test had no effect on judgments or recall but did affect information seeking. Subjects with positive test results were less likely to request a definitive follow-up test when their results were unreliable. The results are interpreted as evidence for independent confirmatory search and denial processes following medical diagnosis.  相似文献   
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