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91.
Background/Objective: Almost no attention has been paid to depression in Friedreich ataxia (FRDA), a highly disabling cerebellar degenerative disease. Our aim was to study the presence and the profile of depressive symptoms in FRDA and their relationship with demographic-disease variables and cognitive processing speed. Method: The study groups consisted of 57 patients with a diagnosis of FRDA. The Beck Depression Inventory-II was used to assess symptoms of depression. Speed of information processing was measured with a Choice Reaction time task. Results: The mean BDI score for patients was significantly higher than the mean score in the general population. Twenty one percent of participants scored in the moderate/severe range. A Cognitive-Affective score and a Somatic-Motivational score was calculated for each patient. Patients’ scores in both dimensions were significantly higher than the scores in the general population. Demographic and disease variables were not related with symptoms of depression, except for severity of ataxia. Depressive symptoms predict cognitive reaction times. The greater proportion of variance was explained by the Cognitive-Affective dimension. Conclusions: Our data show that both somatic-motivational and cognitive affective symptoms of depression are frequent in individuals with FRDA. In addition, depressive symptoms may influence cognition, especially, the cognitive and affective symptoms.  相似文献   
92.
Crewmember performance before, during, and after spaceflight   总被引:1,自引:0,他引:1  
The development of technologies for monitoring the welfare of crewmembers is a critical requirement for extended spaceflight. Behavior analytic methodologies provide a framework for studying the performance of individuals and groups, and brief computerized tests have been used successfully to examine the impairing effects of sleep, drug, and nutrition manipulations on human behavior. The purpose of the present study was to evaluate the feasibility and sensitivity of repeated performance testing during spaceflight. Four National Aeronautics and Space Administration crewmembers were trained to complete computerized questionnaires and performance tasks at repeated regular intervals before and after a 10-day shuttle mission and at times that interfered minimally with other mission activities during spaceflight. Two types of performance, Digit-Symbol Substitution trial completion rates and response times during the most complex Number Recognition trials, were altered slightly during spaceflight. All other dimensions of the performance tasks remained essentially unchanged over the course of the study. Verbal ratings of Fatigue increased slightly during spaceflight and decreased during the postflight test sessions. Arousal ratings increased during spaceflight and decreased postflight. No other consistent changes in rating-scale measures were observed over the course of the study. Crewmembers completed all mission requirements in an efficient manner with no indication of clinically significant behavioral impairment during the 10-day spaceflight. These results support the feasibility and utility of computerized task performances and questionnaire rating scales for repeated measurement of behavior during spaceflight.  相似文献   
93.
94.
The Program Environment Scale (PES) was developed for use with clients of community-based programs for the severely mentally ill. It is intended to fill the gap in available tools for assessing clients' perceptions of program functioning as it affects their quality of life in a program. Formal pretests were conducted with 121 clients at 12 randomly selected programs near Washington, DC. The final field test used a revised form (29 domains; 129 items) with 221 clients in 22 programs selected randomly throughout the U.S., including Clubhouse, day treatment, psychosocial rehabilitation, and social club programs. Twenty-three subscales met at least five of eight psychometric criteria for internal consistency and discriminant validity. A 24th subscale was retained because of its substantive importance. Successful subscales cover program atmosphere and interactions (program cares about me, energy level, friendliness, openness, staff-client and client-client respect, reasonable rules, availability of positive physical contact, protection from bad touch, staff investment in their jobs, and confidentiality), client empowerment/staff-client equality (program and treatment empowerment, egalitarian space use), and service components (support for paid work, work importance, emergency access, family activities, housing, public benefits, community activities, medications, substance abuse, and continuity). Subscale validity is indicated by associations of specific service offerings with scores on scales measuring client perceptions of those services, and by an ability to differentiate among program models (i.e., Clubhouses, day treatment programs, and psychosocial rehabilitation programs look different from each other). Subscale scores were not influenced by client characteristics (gender, race, age, diagnosis, number of hospitalizations, length of time in program). The final scale has 97 items and takes about 25 minutes to complete. The PES succeeds in measuring different aspects of programs as clients perceive them. In the programs we visited, directors felt the PES covers the important things they want to know about how clients perceive their program. The PES should become a useful tool both for researchers interested in how client responses to programs may influence their therapeutic outcomes, and for practitioners interested in improving their clients' program experiences and/or increasing convergence of staff and client views of their program.  相似文献   
95.
The evaluation of everyday memory (EM) was reviewed and reconceptualized. EM has established new objectives of study and the development of new methods to reach these objectives . At the basic level, this approach has already produced important discoveries and the development of new principles about memory and functioning. At the clinical level, this new area of investigation has resulted in evaluating deficits of EM, which is defined as what daily life functions remain impaired after a deficit pathology has occurred. A type of evaluation has evolved that is oriented toward treatment and extremely useful in designing rehabilitation programs for individuals with alterations in memory.  相似文献   
96.
Effective and useful interventions often deteriorate when researchers withdraw their direct supervision. We tested the survival of an intervention designed to produce effective weekly meetings in a student housing cooperative without direct researcher supervision. Chairperson performance, proposals completed per hour, and ratings of chairperson performance all increased when resident staff used a training manual, prompting checklist, and performance reviews. Eight years of follow-up revealed continuing high levels of meeting effectiveness. This study demonstrates a methodology for the direct observation and experimental analysis of intervention survival.  相似文献   
97.
Researchers conducting longitudinal studies with children or adults are inevitably confronted with problems of attrition and missing data. Missing data in longitudinal studies is frequently handled by excluding from analyses those cases for whom data are incomplete. This approach to missing data is not optimal. On the one hand, if data are missing at random, then dropping incomplete cases ignores information collected on those cases that could be used to improve estimates of population parameters (e.g., means, variances, covariances, and growth rates) and improve the power of significance tests of statistical hypotheses. On the other hand, if data are not missing at random, then dropping incomplete cases leads to biased parameter estimates and hypothesis tests that may be internally and externally invalid. This study uses three years of follow-up data from a longitudinal investigation of neuropsychological outcomes of cancer in children to demonstrate the problems presented by missing data in repeated measures designs and some solutions. In evaluating potential biasing effects of attrition, the study extends previous research on neuropsychological outcomes in pediatric cancer by inclusion of patients whose disease had relapsed, and by comparison of surviving and nonsurviving patients. Although the data presented have specific relevance to the study of neuropsychological outcome in pediatric cancer, the problems of missing data and the solutions presented are relevant to a wide variety of diseases and conditions of interest to researchers in child and adult neuropsychology.  相似文献   
98.
A. P. Grieve 《Psychometrika》1984,49(2):257-267
The locally best invariant test statistic for testing sphericity of normal distributions is shown to be a simple function of the Box/Geisser-Greenhouse degrees of freedom correction factor in a repeated measures design. Because of this relationship it provides a more intuitively appealing test of the necessary and sufficient conditions for valid F-tests in repeated measures analysis of variance than the likelihood ratio test. The properties of the two tests are compared and tables of the critical values of the Box/Geisser-Greenhouse correction factor are given.  相似文献   
99.
Two sources of variability must each be considered when examining change in level between two sets of data obtained by human observers; namely, variance within data sets (phases) and variability attributed to each data point (reliability). Birkimer and Brown (1979a, 1979b) have suggested that both chance levels and disagreement bands be considered in examining observer reliability and have made both methods more accessible to researchers. By clarifying and extending Birkimer and Brown's papers, a system is developed using observer agreement to determine the data point variability and thus to check the adequacy of obtained data within the experimental context.  相似文献   
100.
Interval by interval reliability has been criticized for "inflating" observer agreement when target behavior rates are very low or very high. Scored interval reliability and its converse, unscored interval reliability, however, vary as target behavior rates vary when observer disagreement rates are constant. These problems, along with the existence of "chance" values of each reliability which also vary as a function of response rate, may cause researchers and consumers difficulty in interpreting observer agreement measures. Because each of these reliabilities essentially compares observer disagreements to a different base, it is suggested that the disagreement rate itself be the first measure of agreement examined, and its magnitude relative to occurrence and to nonoccurrence agreements then be considered. This is easily done via a graphic presentation of the disagreement range as a bandwidth around reported rates of target behavior. Such a graphic presentation summarizes all the information collected during reliability assessments and permits visual determination of each of the three reliabilities. In addition, graphing the "chance" disagreement range around the bandwidth permits easy determination of whether or not true observer agreement has likely been demonstrated. Finally, the limits of the disagreement bandwidth help assess the believability of claimed experimental effects: those leaving no overlap between disagreement ranges are probably believable, others are not.  相似文献   
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