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Informed consent, parental awareness, and reasons for participating in a randomised controlled study
M van Stuijvenberg MH Suur S de Vos GC Tjiang EW Steyerberg G Derksen-Lubsen HA Moll 《Archives of disease in childhood》1998,79(2):120-125
BACKGROUND: The informed consent procedure plays a central role in randomised controlled trials but has only been explored in a few studies on children. AIM: To assess the quality of the informed consent process in a paediatric setting. METHODS: A questionnaire was sent to parents who volunteered their child (230 children) for a randomised, double blind, placebo controlled trial of ibuprofen syrup to prevent recurrent febrile seizures. RESULTS: 181 (79%) parents responded. On average, 73% of parents were aware of the major study characteristics. A few had difficulty understanding the information provided. Major factors in parents granting approval were the contribution to clinical science (51%) and benefit to the child (32%). Sociodemographic status did not influence initial participation but west European origin of the father was associated with willingness to participate in future trials. 89% of participants felt positive about the informed consent procedure; however, 25% stated that they felt obliged to participate. Although their reasons for granting approval and their evaluation of the informed consent procedure did not differ, relatively more were hesitant about participating in future. Parents appreciated the investigator being on call 24 hours a day (38%) and the extra medical care and information provided (37%) as advantages of participation. Disadvantages were mainly the time consuming aspects and the work involved (23%). CONCLUSIONS: Parents' understanding of trial characteristics might be improved by designing less difficult informed consent forms and by the investigator giving extra attention and information to non-west European parents. Adequate measures should be taken to avoid parents feeling obliged to participate, rather than giving true informed consent. 相似文献
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S. J. Cowen R. J. N. Allcock S. J. Comer J. D. Wetherall D. M. Groth 《Conservation Genetics Resources》2013,5(3):623-625
The Noisy Scrub-bird is an endangered species of songbird endemic to the south coast of Western Australia that has undergone a major and prolonged population bottleneck. Using shotgun 454 next-generation DNA sequencing we have identified and characterised ten polymorphic microsatellite loci in this species. Observed allelic diversity was relatively low (2–5 alleles per locus) and significant deviations from Hardy–weinberg Equilibrium observed, although the presence of null alleles was only postulated for two loci. The microsatellite loci characterised in this study will be useful in a future population genetics studies in this endangered species. 相似文献
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Rearrangement of the T cell receptor gamma-chain gene in childhood acute lymphoblastic leukemia 总被引:4,自引:0,他引:4
We analyzed rearrangements of the T cell receptor gamma-chain (T gamma) gene as well as rearrangements of the T cell receptor beta-chain (T beta) gene and immunoglobulin heavy-chain (IgH) gene in 68 children with acute lymphoblastic leukemia (ALL). All 15 patients with T cell ALL showed rearrangements of both T beta and T gamma genes. Twenty-four of 53 non-T, non-B ALL patients (45%) showed T gamma gene rearrangements and only 14 of these also showed T beta gene rearrangements. Only a single patient rearranged the T beta gene in the absence of T gamma gene rearrangement. The rearrangement patterns of the T gamma gene in non-T, non-B ALL were quite different from those observed in T cell ALL, as 20 of 23 patients retained at least one germline band of the T gamma gene. In contrast, all T cell ALL patients showed no retention of germline bands. These data indicate that rearrangement of the T gamma gene is not specific for T cell ALL. Further, the results also suggest that T gamma gene rearrangement precedes T beta gene rearrangement. The combined analysis of rearrangement patterns of IgH, T beta, and T gamma genes provides new criteria for defining the cellular origin of leukemic cells and for further delineation of leukemia cell heterogeneity. 相似文献
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OBJECTIVE: To evaluate the functional impact of an individualized outpatient pulmonary rehabilitation program in end-stage chronic obstructive pulmonary disease (COPD). METHODS: Patients with end-stage COPD were admitted into a 6-week comprehensive outpatient pulmonary rehabilitation program that was "packaged" for each patient. We compared spirometric parameters, exercise tolerance, level of breathlessness, and intensity of work before and after rehabilitation. RESULTS: Of 45 eligible patients, only 14 consented to participate in the study. All 14 patients had forced expiratory volume in 1 second <35% of predicted, and 10 patients (72%) had a 6-minute walk test <180 m. The level of breathlessness was between 7 (moderate to severely breathless) and 10 (maximally breathless) on the Visual Analogue Scale in all patients. After the program, there was significant improvement in the FEV 1 P = 0.04), forced vital capacity P = 0.0045), 6-minute walk test P = 0.00047), and shuttle-walk test (9 of 14 patients). All patients had some improvement in level of dyspnea. CONCLUSIONS: Individualized outpatient pulmonary rehabilitation in end-stage COPD can produce a measurable improvement in spirometry and exercise tolerance with a favorable impact on the level of physical activity. 相似文献
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