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901.
Outcome measures for smoking cessation are reviewed and evaluated, including 3 self-report measures and 3 biochemical validation measures. Point prevalence reflects the percentage of participants taking action, prolonged abstinence reflects those in the maintenance stage, and continuous abstinence reflects those who progress from action to maintenance without lapsing or relapsing. Biochemical assessments are primarily measures of point prevalence abstinence. The desirability of biochemical validation is a particularly controversial and critical issue. Three factors affect the accuracy of self-report: Type of Population, Type of Intervention, and Demand Characteristics. False-negative rates are generally low. Three broad issues impact on decisions to use biochemical validation: (a) alternative explanations for false positives, (b) refusal rate problems, and (c) the effect of inaccuracy on intervention assessment.  相似文献   
902.
Classical factor analysis assumes a random sample of vectors of observations. For clustered vectors of observations, such as data for students from colleges, or individuals within households, it may be necessary to consider different within-group and between-group factor structures. Such a two-level model for factor analysis is defined, and formulas for a scoring algorithm for estimation with this model are derived. A simple noniterative method based on a decomposition of the total sums of squares and crossproducts is discussed. This method provides a suitable starting solution for the iterative algorithm, but it is also a very good approximation to the maximum likelihood solution. Extensions for higher levels of nesting are indicated. With judicious application of quasi-Newton methods, the amount of computation involved in the scoring algorithm is moderate even for complex problems; in particular, no inversion of matrices with large dimensions is involved. The methods are illustrated on two examples.Suggestions and corrections of three anonymous referees and of an Associate Editor are acknowledged. Discussions with Bob Jennrich on computational aspects were very helpful. Most of research leading to this paper was carried out while the first author was a visiting associate professor at the University of California, Los Angeles.  相似文献   
903.
The delayed-JOL effect is the finding in which judgments of learning (JOLs) are more accurate at predicting eventual recall when they are made a short time after study rather than immediately after study. The present research replicated this effect and found that the kind of cue that is used for JOLs is critical. In particular, following the study of stimulus-response paired associates, there is an extremely robust delayed-JOL effect when the cue for JOLs is the stimulus alone (every one of 45 subjects showed the effect); however, there is little, if any, delayed-JOL effect when the cue for JOLs is the stimulus-response pair. This finding has important implications for education: To have the greatest accuracy at predicting eventual recall, a person should make JOLs not immediately after study but, instead, shortly after study (i.e., delayed JOLs) with the cue for JOLs being the stimulus alone. The theoretical mechanisms for the delayed-JOL effect are currently unknown, but some speculations are offered.  相似文献   
904.
The Fear Survey Schedule for Children-Revised (FSSC-R), Revised-Children's Manifest Anxiety Scale (RCMAS), and the Modified State-Trait Anxiety Inventory for Children (STAIC-M) are three widely used self-report measures of childhood anxiety. While previous studies have established the reliability of these measures, their validity in discriminating anxious from non-anxious youngsters remains to be established. The present study examines the discriminant validity of the three measures by comparing clinic referred samples of boys with an anxiety disorder (n=105) or ADHD (n=59) with a community sample of never-psychiatrically-ill boys (n=49). Results indicated that the two patient groups differed significantly from the never-psychiatrically-ill group on the RCMAS and STAIC-M, but the anxious and ADHD groups did not differ from each other. None of the three groups differed on the FSSC-R. The implications of these findings for the assessment of childhood anxiety disorders are discussed.  相似文献   
905.
This study tested whether sensitivity to aversive events is a concomitant versus antecedent/consequent of depression. Twenty currently depressed subjects, twenty subjects with remitted depression, and twenty control subjects completed psychophysiological and learning tasks involving aversive components. Both currently depressed and remitted subjects, when compared to control subjects, exhibited greater decreases in skin resistance response reactions to negative social scenes and a greater sensitivity to extinction in the learning condition involving an aversive component. The fact that the responses of remitted subjects were very similar to those of currently depressed subjects on both tasks is consistent with the view that sensitivity to aversive events is an antecedent or consequent of depression, as opposed to being only a concomitant. The results also provide some support for the passive avoidance model of depression.This study was based on portions of a doctoral dissertation by the first author, with the second author as chairperson, at the University of North Carolina at Greensboro.This research was aided by a Grant-in-Aid of Research to the first author from Sigma Xi, The Scientific Research Society, an award from the Jill Shelby Memorial Fund to the first author, and support from National Institute of Mental Health Grant MH17071, awarded to C. R. Snyder.Portions of this paper were presented at the meeting of the American Psychological Association, New Orleans, August 1989, and at the meeting of the Association for the Advancement of Behavior Therapy, Washington, DC, November, 1989.  相似文献   
906.
In a study of how aviation expertise influences age differences in narrative processing, young and older pilots and nonpilots read and recalled aviation and general narratives. They chose referents for sentences referring to a protagonist or minor character mentioned 1 sentence (recent character) or 3 sentences (distant character) before this target sentence. All groups chose referents less accurately for sentences about distant and minor characters than about recent and protagonist characters, perhaps because these referents were less likely to be in working memory. Young readers and pilots were more accurate for distant and minor character target sentences in aviation narratives, and recalled aviation narratives more accurately. Expertise did not reduce age differences. Expertise differences may reflect decreased demands on working memory capacity, and age declines may reflect reduced capacity.  相似文献   
907.
Providing genetic services to families who do not speak English and whose cultures are quite diverse presents a unique challenge to genetic specialists. One approach that is being employed successfully is the use of specially trained genetic assistants to provide outreach, case finding, referral, support, interpretation, advocacy, and follow-up counseling. A basic genetic assistant training program for five bicultural/bilingual Southeast Asian case managers is described. The course syllabus can be used to train health workers who represent a variety of cultures and languages.  相似文献   
908.
Two experiments are reported that contrast rotating versus fixed electronic map displays, which pilots used for a simulated approach to a landing. In Experiment 1, a rotating versus fixed-map display was experimentally crossed with a two-dimensional (2D) versus three-dimensional (3D) view (perspective map) as pilots' ability to maintain the flight path and demonstrate awareness of the location of surrounding terrain features were assessed. Rotating displays supported better flight path guidance and did not substantially harm performance on terrain awareness tasks. 3D displays led to a substantial cost for vertical control but did not differ from 2D displays in lateral control. In Experiment 2, pilots flew with the rotating 2D display and with an improved version of the rotating 3D display, designed to reduce the ambiguity of representing altitude information. Vertical control improved as a result of the 3D display design improvement, but lateral control did not. The results are discussed in terms of the costs and benefits of presenting information in 3D, ego-referenced format for both flight path control and terrain awareness.  相似文献   
909.
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