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991.
A multitrait-multimethod design was used to test Jessor and Jessor's (1977) problem behavior theory with a sample of adolescents, their parents, and peers. Behaviors included general deviance, drug use, low academic motivation, and precocious sexual behavior. While research has supported this theory, the reliance on self-report data for the majority of this work may threaten the validity of these findings. Results from hierarchical confirmatory factor analyses indicated that the convergent and discriminant validity of the seven behavior constructs was high and method effects were low. A two-factor second-order model, representing General Drug Use and Other Problem Behavior, accounted for a larger proportion of variance in the lower order factors compared to a single-factor model.This research was supported by Grant DA 03706 from the National Institute on Drug Abuse.  相似文献   
992.
The effects of reducing teacher questions and increasing pauses on student talk during morning news sessions were investigated. The length of student discourse was observed during random 10-min samples of the lesson, together with frequency counts of teacher questions and pauses. Concomitant measures of teacher praise, directives, control statements and student call-outs were also obtained. Within the constraints of a within-subjects reversal design (ABAB), experimentally reducing teacher questions and replacing these with pauses and/or topic-related statements was associated with an increase in child discourse. Teacher praise and directives did not systematically alter across experimental phases but both teacher control statements and child call-outs reduced during the intervention phases. Reducing teacher questions and increasing the use of pauses by the teacher was associated with increases in student discourse without adversely affecting classroom behavior. These results support the hypothesis that teacher questions foil pupil talk in morning news thereby obstructing the pedagogical value of these sessions.  相似文献   
993.
The historical background of the discovery of adverse health effects of medicines, food additives, pesticides, and other chemicals is reviewed, and the development of national and international regulations and testing procedures to protect the public against the toxic effects of these drugs and chemicals is outlined. Ethical considerations of the safety evaluation of drugs and chemicals by human experimentation and animal toxicity studies, ethical problems associated with clinical trials, with the falsification of clinical and toxicological data, and with inadequate experimental methodology, are reviewed, and the ethics of the marketing of drugs and their post-marketing surveillance, are similarly considered. These ethical problems are illustrated with many specific examples, including the drugs neoarsphenamine, chloramphenicol, thalidomide, diethyl stilboestrol and benoxaprofen.  相似文献   
994.
We report the effects of using a urine alarm, typically employed for nocturnal enuresis, to treat chronic diurnal enuresis in a 15-year-old female resident at Boys' Town. The results of an ABAB reversal design indicate that the alarm eliminated wetting in both treatment phases and that continence was maintained at 3- and 6-month follow-up.  相似文献   
995.
Within the past decade, the wraparound approach has gained significant popularity in providing services to children with challenging social and family needs. While a plethora of wraparound programs have been developed and studies have been conducted to assess their effectiveness, the need to develop instruments that measure the implementation of wraparound services is clear. The purpose of the present study was to evaluate the reliability of a scale that measures wraparound services. In this study, the Wraparound Observation Form (WOF), was developed to evaluate the implementation of the wraparound process in treatment planning meetings. The WOF includes 34 closed-ended items that requires the respondent to note the occurrence or non-occurrence of specific events or behaviors at treatment planning meetings. In the present study, two data collectors attended planning meetings and independently completed the WOF. The inter-rater reliability was 95%. The WOF appears to be a reliable instrument and be appropriate in evaluating wraparound services.  相似文献   
996.
As many as 80% of the individuals with severe or profound mental retardation exhibit feeding problems. Although behavioral interventions have been used to treat these problems, no assessment procedure for determining a functional relationship between a person's acceptance of food and the type and texture of that food has been reported. The purpose of this study was to test a behavioral assessment procedure for a feeding problem of limited intake. Five individuals with severe or profound mental retardation were fed 10 to 12 types of foods with one or more textures. Behavioral categories of acceptance, rejection, expulsion, and other negative behavior were recorded. Results indicated that each subject fit into one of four categories of feeding problems: (a) total refusal, (b) type selectivity, (c) texture selectivity, or (d) type and texture selectivity. Thus, although all 5 subjects exhibited limited intake, the food characteristics correlated with the problem were different for each individual. Results suggest that treatments for limited intake may be based on assessments that show the association of food type or texture to a person's rejection or expulsion of food.  相似文献   
997.
A group of young delinquents clinically rated as manifesting a tendency to react with anxiety and tension was compared with a group from the same prison with predominantly 'psychopathic' traits according to clinical ratings. The delinquents were subjected to electrical pain stimulation and tested with a battery of tests and personality inventories. In line with the hypotheses, the more anxiety-prone delinquents showed greater sensitivity to pain, had lower scores in the Leg Persistence Test, shorter reaction times and more errors in an auditive choice reaction test. There were no significant differences with regard to the inventory variables.  相似文献   
998.
Persistence of excitation and neural adaptation are competing theories proposed to explain the mechanisms underlying psychophysical forward masking. Previous research has been directed towards finding models that accurately describe the phenomenon but cannot account for the underlying explanation. The current study was designed to determine which theory best accounts for results obtained from behavioral gap duration adjustment tasks. Thirteen adults adjusted the gap within asymmetrical noise markers to be subjectively equal to the gap within equal-intensity-noise markers. The duration of the perceived gap between the asymmetrical markers is expected to vary depending on which theory dominates perception. The persistence of excitation mechanism would lead to longer duration gaps when the second noise marker is lower in intensity than the preceding. Neural adaptation would result in matched gaps that are shorter in duration when the second noise marker was lower in level. The outcome of our data analysis is consistent with the persistence of excitation as a dominant mechanism in forward masking.  相似文献   
999.
There is a recent increase in interest of Bayesian analysis. However, little effort has been made thus far to directly incorporate background knowledge via the prior distribution into the analyses. This process might be especially useful in the context of latent growth mixture modeling when one or more of the latent groups are expected to be relatively small due to what we refer to as limited data. We argue that the use of Bayesian statistics has great advantages in limited data situations, but only if background knowledge can be incorporated into the analysis via prior distributions. We highlight these advantages through a data set including patients with burn injuries and analyze trajectories of posttraumatic stress symptoms using the Bayesian framework following the steps of the WAMBS-checklist. In the included example, we illustrate how to obtain background information using previous literature based on a systematic literature search and by using expert knowledge. Finally, we show how to translate this knowledge into prior distributions and we illustrate the importance of conducting a prior sensitivity analysis. Although our example is from the trauma field, the techniques we illustrate can be applied to any field.  相似文献   
1000.
We report data from an experiment in which participants performed immediate serial recall of visually presented words with or without articulatory suppression, while also performing homophone or rhyme detection. The separation between homophonous or rhyming pairs in the list was varied. According to the working memory model (Baddeley, 1986; Baddeley & Hitch, 1974), suppression should prevent articulatory recoding. Nevertheless, rhyme and homophone detection was well above chance. However, with suppression, participants showed a greater tendency to false-alarm to orthographically related foils (e.g., GIVE–FIVE). This pattern is similar to that observed in short-term memory patients.  相似文献   
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