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71.
Three experiments examined repeated retention testing effects in a contextual interference (CI) protocol. Retention was assessed at 10 min and 24 hr following acquisition or at just 24-hr for the one-test conditions. Experiments 1 and 2 used speeded-response key-pressing tasks. Dependent measures were total time and errors. Experiment 3 used sequential-timing tasks. Dependent measures were absolute error and absolute constant error Results revealed CI effects in each experiment. Repeated retention testing effects were not found in Experiments 1 and 3. Experiment 2 revealed superior performance by the two-test condition compared to the one-test condition. This result was qualified by possible practice effects during the 10-min test. It was concluded that repeated retention testing does not present problems for most studies of CI.  相似文献   
72.
Accurate measurement of physical activity is fundamentally important in epidemiological research of physical activity behavior A widely used telephone-based physical activity questionnaire was compared with other methods of administration and objective measures (pedometers and accelerometers) among 80 adults (43 women). The telephone questionnaire was comparable to both the self-administered form and international telephone-administered equivalent. Although moderate correlation coefficients with objective measures supported the use of the questionnaire, wide prediction intervals generated using Bland Altman methods highlighted large discrepancies between the measures, particularly in the moderate intensity category. These findings illustrate the limitations of correlation coefficients in validation studies and the inaccuracy of self-report questionnaires in measuring physical activity.  相似文献   
73.
Vitamin B12 deficiency can present with neurologic and psychiatric symptoms without macrocytic anaemia. We describe a case of late-onset cobalamin C deficiency which typically presents with normal serum vitamin B12 concentrations, posing an additional diagnostic challenge. A 23-year-old woman with decreased muscle strength and hallucinations was diagnosed with ‘catatonic depression’ and admitted to a residential mental health facility. She was referred to our hospital for further investigation 3 months later. Heteroanamnesis revealed that the symptoms had been evolving progressively over several months. Magnetic resonance imaging (MRI) of the brain showed diffuse symmetrical white matter lesions in both hemispheres. Routine laboratory tests including vitamin B12 and folic acid were normal except for a slight normocytic, normochromic anaemia. Over the next 6 weeks her symptoms deteriorated, and she became unresponsive to stimuli. A new MRI scan showed progression of the white matter lesions. The neurologist requested plasma homocysteine (Hcys) which was more than 8 times the upper limit of normal. Further testing revealed increased methylmalonic acid and the patient was diagnosed with adult-onset cobalamin C deficiency. This case illustrates that Hcys and/or methylmalonic acid should be determined in patients presenting with neuropsychiatric symptoms suggestive of vitamin B12 deficiency with a normal serum vitamin B12 to rule out a late-onset cobalamin C deficiency.  相似文献   
74.
Cognitive theory suggests that a key to expert performance lies in the internal organization of the expert's knowledge. The authors contend that the type of technical illustration used during instruction influences knowledge organization and greatly impacts students' understanding of the content. This paper describes an experimental study that tested the impact of one type of conceptual illustration on students' understanding of the structure, function, and behavior of complex technical systems. The results show that supplementing traditional technical instruction with functional flow diagrams can improve overall system understanding. The functional flow diagrams were also found to be an effective instructional aid for enhancing students' conceptual understanding of the causal behavior of systems. In addition, the use of the functional flow diagram was found to significantly improve the subjects' ability to construct conceptual models that were similar to those of an expert. The implications of using conceptual diagrams for technical instruction are discussed and recommendations for future research in this area are provided.  相似文献   
75.
Recent concern about school violence has increased demands on school psychologists to respond to safety concerns on their school campuses. In this study, 123 school psychologists responded to a survey about their perceptions, experiences, and readiness to meaningfully address school violence. School psychologists reported that they do not worry about their personal safety at school (78%), but most felt unprepared to deal with school violence (73%) and had received no specialized training in this area (85%). A principal components analysis of the types of violence school psychologists perceived to occur on their campuses identified a range of incidents from bullying to antisocial behavior. School psychologists working in inner-city schools were more likely to believe that their schools had high levels of violence (45.6%) compared with those working in urban-not inner-city (14.3%), suburban (4.9%), or rural (0%) schools. Recommendations to prepare school psychologists to help prevent, reduce, and respond to campus violence are discussed. © 1996 John Wiley & Sons, Inc.  相似文献   
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77.
This 5-year follow-up study examined the predictive validity of the Kaufman Assessment Battery for Children (K-ABC) for 39 children identified during preschool as exhibiting language impairment (n = 10), behavior control deficits (n = 13), or normal language and behavioral development (n = 16). Mean age at follow-up was 9.75 years. The results generally supported the predictive validity of the K-ABC (p<.001). However, analyses by group indicated that the relationship between baseline K-ABC and follow-up K-ABC, language, and achievement measures for the language-impaired subjects was weak (p>.05). Although these results must be interpreted cautiously because of the small sample size, they suggest that for young children likely to be referred as at risk for future learning problems, the K-ABC may not be useful for prediction of later cognitive skills. Implications for practitioners are discussed.  相似文献   
78.
“Formulation of instructional strategy to match subject matter and learner requirements” is an integral part of most instructional design models (Andrews & Goodson, 1980, p.5). Yet the meaning and purpose of instructional strategies in these design models vary considerably. An instructional strategy in traditional design models usually refers to the selection of instructional delivery vehicles (e.g., lecture, demonstration, computer-assisted instruction) and support activities (e.g., practice exercises, tutoring) (cf. Tracey, Flynn, <& Legere, 1970). Contrast those conceptions with the many instructional strategies described in elaboration theory (Reigeluth & Stein, 1983), such as sub-sumptive sequencing, internally consistent orienting structures, synthesizers, summarizers, and cognitive strategy activators. What is obvious from these disparate conceptions is that instructional designers do not share a consistent definition of instructional strategies. Many of the activities that are referred to as instructional strategies are not in fact strategies, but rather are presentation vehicles. In this article, we first define instructional strategies and tactics in the context of an iterative design model. Instructional strategies are then distinguished from instructional tactics, which are the implementation of strategies. We then list the range of instructional strategies and tactics that implement them. Finally, we provide a decision tree for assisting designers to select appropriate instructional tactics.  相似文献   
79.
80.
This study investigated the convergent and discriminant relationships between a children's life satisfaction measure, the Students' Life Satisfaction Scale (SLSS; Huebner, 1991a), and a widely used self-concept measure, the Piers-Harris Self-Concept Scale (Piers, 1984). Correlational and regression analyses demonstrated stronger relationships between the SLSS and the Piers-Harris Happiness and Satisfaction subscale compared to the other Piers-Harris subscales. The results of a conjoint principal components analysis also revealed predictable overlap between the SLSS and the Piers-Harris Happiness and Satisfaction subscale. Implications for future research are discussed.  相似文献   
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