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- Lynöe, Niels, et al.
(författare)
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Informed consent : study of quality of information given to participants in a clinical trial
- 1991
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Ingår i: The BMJ. - 1756-1833. ; 303:6803, s. 610-613
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To determine whether the participants in a clinical trial had perceived adequate information about the trial according to the guidelines of the Declaration of Helsinki. DESIGN: About 18 months after the end of a gynaecological clinical trial the participants received a questionnaire by post, which focused on the quality of the information given to them before entering the trial. Neither researchers nor participants were aware in advance that the trial would become the subject of this follow up investigation. SETTING: Eight different centres in Sweden. SUBJECTS: 43 women out of the 53 who completed the trial (mean (range) age 23 (16 to 35) years) returned the questionnaire. MAIN OUTCOME MEASURES: Adequacy of the information (based on requirements of the Declaration of Helsinki) to enable the following: understanding of the aims of the study; awareness of what participation meant; and awareness of the possibility of withdrawing from participation at any time. Motives for agreeing to participate, and a subjective evaluation of the given information were also recorded. RESULTS: All but one of the participants had been aware that they were taking part in a research project. Five women stated that they had not been aware that a second laparoscopy was performed only for research reasons. Seven women reported that they had not been aware of the meaning of participating in the project and 17 that they had had no information about the possibility of withdrawing from the study whenever they wanted. In the subjective rating 22 women considered the information given as good or very good. There was a systematic variation in the quality of the given information among the eight centres. CONCLUSION: Although all but one of the participants had been aware that they were taking part in a clinical trial, the quality of the information understood and recalled by participants varied, and in many cases clearly did not meet the guidelines of the Declaration of Helsinki. Variations among centres in participants' perception of information suggest that deficiencies in perception may be caused by informers rather than the participants.
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| 2. |
- Mannheimer, C, et al.
(författare)
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Effects of spinal cord stimulation in angina pectoris induced by pacing and possible mechanisms of action.
- 1993
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Ingår i: BMJ (Clinical research ed.). - 0959-8138. ; 307:6902, s. 477-80
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Tidskriftsartikel (refereegranskat)abstract
- To investigate the effects of spinal cord stimulation on myocardial ischaemia, coronary blood flow, and myocardial oxygen consumption in angina pectoris induced by atrial pacing.The heart was paced to angina during a control phase and treatment with spinal cord stimulation. Blood samples were drawn from a peripheral artery and the coronary sinus.Multidisciplinary pain centre, department of medicine, Ostra Hospital, and Wallenberg Research Laboratory, Sahlgrenska Hospital, Gothenburg, Sweden.Twenty patients with intractable angina pectoris, all with a spinal cord stimulator implanted before the study.Spinal cord stimulation increased patients' tolerance to pacing (p < 0.001). At the pacing rate comparable to that producing angina during the control recording, myocardial lactate production during control session turned into extraction (p = 0.003) and, on the electrocardiogram, ST segment depression decreased, time to ST depression increased, and time to recovery from ST depression decreased (p = 0.01; p < 0.05, and p < 0.05, respectively). Spinal cord stimulation also reduced coronary sinus blood flow (p = 0.01) and myocardial oxygen consumption (p = 0.02). At the maximum pacing rate during treatment, all patients experienced anginal pain. Myocardial lactate extraction reverted to production (p < 0.01) and the magnitude and duration of ST segment depression increased to the same values as during control pacing, indicating that myocardial ischaemia during treatment with spinal cord stimulation gives rise to anginal pain.Spinal cord stimulation has an anti-anginal and anti-ischaemic effect in severe coronary artery disease. These effects seem to be secondary to a decrease in myocardial oxygen consumption. Furthermore, myocardial ischemia during treatment gives rise to anginal pain. Thus, spinal cord stimulation does not deprive the patient of a warning signal.
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