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61.
62.
This study aimed to develop a short Osteoporosis-Specific Quality of Life Questionnaire based on the assemblage (equating) of the items of two existing questionnaires (OQLQ and QUALEFFO). For this purpose, each questionnaire was administered by random assignment to a different group of female patients (OQLQ, n = 172; QUALEFFO, n = 166) with vertebral fractures due to osteoporosis. A common anchor test (SF-36) was also given to both groups. Seven different sets of OQLQ-QUALEFFO common items were defined by inspecting their own correlation with the scores of the eight dimensions of the SF-36. Within each set, equating consisted in connecting the OQLQ and QUALEFFO through their link with the SF-36. Equating was carried out through the Rasch mathematical model. Quantitative (item statistics) and qualitative reductions (expert opinion) of the equated sets resulted in a 16-item questionnaire. Although the new instrument requires further empirical validation, it provides a promising alternative to currently existing longer questionnaires for use in clinical practice.  相似文献   
63.
OBJECTIVES: Planned neck dissection after chemoradiation (CR) is often advocated in patients with head and neck squamous cell cancer (HNSCC) with advanced nodal disease who demonstrate a clinical complete response to CR because identification of residual occult nodal disease is difficult. We sought to investigate the utility of positron emission tomography-computed tomography (PET-CT) in identifying patients with occult nodal disease after CR. STUDY DESIGN: Nonrandomized retrospective cohort analysis. MATERIALS AND METHODS: The medical records of all patients treated with primary CR for advanced HNSCC with N2 or N3 disease from December 2003 to June 2005 were reviewed. Patients with a clinical complete response were eligible for inclusion if PET-CT performed at 8 to 10 weeks after CR showed no evidence of distant disease and they were treated with a planned neck dissection. RESULTS: Seventeen patients met study criteria. PET-CT was positive for residual nodal disease in 11 (64.7%) patients, with a standardized uptake value (SUV) range of 1.7 to 3.8. Pathologic examination revealed residual viable carcinoma in five (29.4%) patients, with tumor size ranging from 2.0 to 9.5 mm. Carcinoma was present in 2 of 11 (18.2%) patients with positive PET-CT scans and 3 of 6 (50%) patients with negative PET-CT scans. The sensitivity and specificity of PET-CT in predicting occult nodal disease was 40% and 25%, respectively. There was no correlation between PET-CT findings and histologic findings (P = .26) or between SUV and size of viable tumor (P = .67). CONCLUSIONS: A significant proportion of HNSCC patients with advanced neck disease harbor residual occult metastases after CR. PET-CT is not sufficiently specific or sensitive to reliably predict the need for posttreatment neck dissection.  相似文献   
64.
General population preferences for standardized health states are usually obtained for chronic health states. The primary objective of this study was to analyze the feasibility and validity of using time trade-off (TTO) and a visual analog scale (VAS) to elicit preference values for temporary health states (THS=1 year duration, followed by normal health). Subjects were a random sample (n=300) of the general population. 43 health states generated by the EuroQo-5D were valued. The VAS proved slightly more feasible than the TTO. At aggregate level, correlations between VAS and TTO values were high (Spearman r=0.98), and VAS ratings had slightly greater internal consistency and agreement with rank order preferences than the TTO. TTO values were higher than VAS values, and compression of TTO values suggested substantial reluctance to trade. The effect of age on values was reversed between methods, with older respondents scoring higher on the VAS and lower on the TTO, than other age groups. In conclusion, although the VAS proved to be slightly more feasible than the TTO, with slightly greater empirical validity, further research using a wider range of methods to test validity is required before a definitive conclusion on the relative empirical validity of the two valuation techniques can be drawn.  相似文献   
65.
Abstract The notion that history is a record of continuous improvement has come to dominate the Western view of the world. This paper examines how nursing has embraced this ‘Enlightenment project’ and continues to be guided by a faith in ‘history as progress’ despite the fact that its structural position remains one of subordination and struggle. Faith in progress is manifested in nursing historiography and contemporary nursing literature, in the basic tenet of nursing orthodoxy, that professionalization is both inevitable and desirable, in the alignment of nursing with medical science and technology and the belief that Western nursing is the model for nursing world wide. It is argued that this uncritical faith in a continuously improving future has obscured nursing's vision for the future and rendered it powerless in the face of rapid global economic and social change.  相似文献   
66.
The increasing use of health-related quality of life (HRQOL) questionnaires in multinational studies has resulted in the translation of many existing measures. Guidelines for translation have been published, and there has been some discussion of how to achieve and assess equivalence between source and target questionnaires. Our reading in this area had led us, however, to the conclusion that different types of equivalence were not clearly defined, and that a theoretical framework for equivalence was lacking. To confirm this we reviewed definitions of equivalence in the HRQOL literature on the use of generic questionnaires in multicultural settings. The literature review revealed: definitions of 19 different types of equivalence; vague or conflicting definitions, particularly in the case of conceptual equivalence; and the use of many redundant terms. We discuss these findings in the light of a framework adapted from cross-cultural psychology for describing three different orientations to cross-cultural research: absolutism, universalism and relativism. We suggest that the HRQOL field has generally adopted an absolutist approach and that this may account for some of the confusion in this area. We conclude by suggesting that there is an urgent need for a standardized terminology within the HRQOL field, by offering a standard definition of conceptual equivalence, and by suggesting that the adoption of a universalist orientation would require substantial changes to guidelines and more empirical work on the conceptualization of HRQOL in different cultures.  相似文献   
67.
Role of computed tomography in evaluating asbestos related lung disease   总被引:3,自引:0,他引:3  
To find how computed tomography (CT) may be effectively used in individuals with suspected asbestos related lung disease 30 men with a history of exposure to asbestos were studied. All subjects underwent high kilovoltage posteroanterior and left lateral chest radiographs and chest CT. Eighteen were randomly selected asbestos workers referred for routine surveillance. The remaining 12 were patients who had been referred for investigation of respiratory symptoms or abnormal routine chest radiograph, or both, and found to have chest radiographic changes compatible with asbestos related lung disease. In the group referred for routine surveillance both pleural shadowing and pulmonary shadowing were shown on CT but not chest radiographs in only one case. Five were thought to have pleural shadowing on chest radiographs but this was confirmed on CT in only one case. All 12 patients referred for investigation showed pleural shadowing on chest radiographs; this was confirmed in all cases on CT which also showed unsuspected pulmonary shadowing in five cases. These findings suggest that it is not appropriate to use chest CT routinely in all asbestos workers referred for routine surveillance. When CT is used selectively in those with pleural shadowing on plain chest radiography, however, it is helpful in refuting or confirming the presence of pleural disease and may show unsuspected pulmonary shadowing.  相似文献   
68.
    
The increasing use of health-related quality of life (HRQOL) questionnaires in multinational studies has resulted in the translation of many existing measures. Guidelines for translation have been published, and there has been some discussion of how to achieve and assess equivalence between source and target questionnaires. Our reading in this area had led us, however, to the conclusion that different types of equivalence were not clearly defined, and that a theoretical framework for equivalence was lacking. To confirm this we reviewed definitions of equivalence in the HRQOL literature on the use of generic questionnaires in multicultural settings. The literature review revealed: definitions of 19 different types of equivalence; vague or conflicting definitions, particularly in the case of conceptual equivalence; and the use of many redundant terms. We discuss these findings in the light of a framework adapted from cross-cultural psychology for describing three different orientations to cross-cultural research: absolutism, universalism and relativism. We suggest that the HRQOL field has generally adopted an absolutist approach and that this may account for some of the confusion in this area. We conclude by suggesting that there is an urgent need for a standardized terminology within the HRQOL field, by offering a standard definition of conceptual equivalence, and by suggesting that the adoption of a universalist orientation would require substantial changes to guidelines and more empirical work on the conceptualization of HRQOL in different cultures.  相似文献   
69.
70.
It is well known that previous perceptual experiences alter subsequent perception, but the details of the neural underpinnings of this general phenomenon are still sketchy. Here, we ask whether previous experiences with an item (such as seeing a person's face) leads to the alteration of the neural correlates related to processing of the item as such, or whether it creates additional associative connections between such substrates and those activated during prior experience. To address this question, we used magnetoencephalography (MEG) to identify neural changes accompanying subjects' viewing of unfamiliar versus famous faces and hearing the names of unfamiliar versus famous names. We were interested in the nature of the involvement of auditory brain regions in the viewing of faces, and in the involvement of visual regions in the hearing of names. Evoked responses from MEG recordings for the names and faces conditions were localized to auditory and visual cortices, respectively. Unsurprisingly, peak activation strength of evoked responses was larger for famous versus nonfamous names within the superior temporal gyrus (STG), and was similar for famous and nonfamous faces in the occipital cortex. More relevant to the issue of experience on perception, peak activation strength in the STG was larger for viewed famous versus nonfamous faces, and peak activation within the occipital cortex was larger for heard famous versus nonfamous names. Critically, these experience-related responses were present within 150-250 msec of stimulus onset. These findings support the hypothesis that prior experiences may influence processing of faces and names such that perception encompasses more than what is imparted on the senses.  相似文献   
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