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101.
Jones TC 《Science and engineering ethics》2005,11(4):575-587
The history of drug/vaccine development has included major advances guided primarily by risk/benefit analyses concerning the
innovative agent, not by evidence-based clinical trials (Phase I–IV). Because the approval for new drugs is hindered under
the present process, the system requires restructuring.
The Phase I/II study period should be more flexible, using the “environment of knowledge” about the new agent, plus risk/benefit
assessments. Phase III, as presently constructed, does not add new adverse events data, it provides a narrower profile of
drug efficacy than properly done Phase II studies, and placebo-controlled trials continue to raise unresolved ethical and
social issues. Phase III studies should be abandoned for most drugs, and substituted with properly powered Phase II doseranging
studies plus careful post-marketing surveillance. Phase III should be a penalty for poor drug development, not a regulatory
requirement.
To accomplish efficient drug development, greater cooperation between pharmaceutical companies and governments in developing
clinical trials is needed rather than over-regulation. These changes will synchronize the drug development and regulatory
process with the current rapid drug discovery process, reduce drug development time and cost, and improve patient care.
The author is Adjunct Professor of Medicine, Weill Medical College of Cornell University, New York, New York, USA. 相似文献
102.
Avila C Cuenca I Félix V Parcet MA Miranda A 《Journal of abnormal child psychology》2004,32(3):295-304
Seven different laboratory measures of impulsivity were administered to a group of 165 school-aged boys. Parents' and teachers' ratings of Attention Deficit and Hyperactivity Disorder and Oppositional/Defiant Disorder were also obtained. Factor analyses of impulsivity measures revealed the existence of a strong Inhibitory Control Factor including measures derived from Stop Task, the Continuous Performance Test, the Matching Familiar Figures Test, and the Circle Tracing Task. Other forms of impulsivity like resistance to interference, the Wisconsin Card Sorting Test and efficiency in the DRL Task loaded on a second independent factor. The Inhibitory Control factor was correlated with ADHD ratings, whereas the second factor was slightly related to the presence of ODD symptoms. Discussion is focused on the relevance of inhibitory control in impulsivity and ADHD research. 相似文献
103.
The concept of informed consent was one of the most fruitful ideas that deeply changed the relationships between physicians
and their patients from paternalism to respect for the personal autonomy of subjects needing professional medical care. The
great progress in medicine, also involving the pharmaceutical industry, has created an increasing need to perform different
clinical and experimental trials. The evolution of clinical research in the last decades has influenced strongly the design
of these studies. One of the most important changes in this field has been the use of placebo groups in double-blind controlled
studies. The controversies have involved not only the use of placebo when standard or proven treatment was available, but
also some specific problems concerning the procedure of obtaining informed consent in such trials. This paper briefly presents
the evolution of informed consent in Poland as well as different ethical and legal problems concerning informed consent and
the use of placebo controls in clinical trials.
An earlier version of this paper was presented at an international conference, “Placebo: Its Action and Place in Health Research
Today,” held in Warsaw, Poland on 12–13 April, 2003. 相似文献
104.
Singer EA 《Science and engineering ethics》2004,10(1):51-56
The use of placebo in clinical trials has been repeatedly challenged as being unacceptable from an ethical point of view.
The present paper responds to this criticism by taking up the issue in the light of the pertinent provisions of the Helsinki
Declaration. Examples from different therapeutic areas are given that highlight the importance of placebo in situations in
which its use is acceptable according to the Declaration. Particular emphasis is given to the question of active control trials,
which, under conditions of low assay sensitivity, may become an ethically less acceptable approach than the use of a placebo
control.
An earlier version of this paper was presented at an international conference, “Placebo: Its Action and Place in Health Research
Today,” held in Warsaw, Poland on 12–13 April, 2003. 相似文献
105.
The present study investigated the relative extent to which patients' adjustment to chronic low back pain (CLBP) was influenced by their fear-avoidance beliefs, their tendency to catastrophize, and their appraisals of control. Eighty-three CLBP patients completed a series of self-report measures before participating in a physical therapist-led intervention. Hierarchical multiple regression analyses revealed that patients' perceptions of their ability to decrease pain explained a small, but statistically significant, proportion of the variance in pain intensity. In addition, patients' levels of catastrophizing, as well as their fear-avoidance beliefs about both work and physical activity, were independently associated with levels of disability. Interestingly, however, when exploring the relative predictive utility of these three psychological factors, it became evident that fear-avoidance beliefs about physical activity (FABs-PA) were the only significant predictor of patients' disability. Specifically, those patients who exhibited higher levels of FABs-PA tended to report greater levels of disability, even after adjusting for age, sex and pain intensity. 相似文献
106.
Cognitive defusion techniques are designed to reduce the functions of thoughts by altering the context in which they occur, rather than the attempting to alter the form, frequency, or situational sensitivity of the thoughts themselves. Applied technologies designed to produce cognitive defusion seem to lead to reductions in the believability of negative thoughts, but defusion techniques are generally only parts of complex packages and the role of defusion techniques per se is note yet known. The present study examined the impact of a cognitive defusion technique first described by Titchener nearly 90 years ago: rapidly repeating a single word. In series of eight single-case alternating treatment designs, this defusion technique was compared to a distraction task, and to a thought control task on reductions in the discomfort and believability of self-relevant negative thoughts. The cognitive defusion technique reduced both discomfort and believability more so than the comparison approaches. Control studies showed that the effect was probably not due to demand characteristics. 相似文献
107.
This study examined the effect of age and practice on the structure of children's force variability to test the information processing hypothesis that a reduction of sensorimotor system noise accounts in large part for age-related reductions in perceptual-motor performance variability. In the study, 6-year-olds, 10-year-olds, and young adults practiced on 5 consecutive days (15 trials/day), maintaining for 15-s trials a constant level of force (5 or 25% of maximum voluntary contraction) against an object using a pinch grip (thumb and index finger). With increasing age, the amount of force error and variability decreased, but the sequential structure of variability increased in irregularity. With practice, children reduced the amount of variability by changing the structure of the force output so as to be more similar to that of their older counterparts. The findings provide further evidence that practice-driven changes in the structure of force output, rather than a decline in the amount of white noise, largely account for age-related reductions in the amount of force variability. 相似文献
108.
The present experiment examined the one-target advantage (OTA) with regard to saccadic eye movements. The OTA, previously found with manual pointing responses, refers to the finding that movements are executed faster when the limb is allowed to stop on the target compared to the situation where it has to proceed and hit a second target. Using an adapted limb movement OTA task, saccades of 5 degrees and 15 degrees were made to (a) a single target (one-target), (b) one target and immediately to another target without a change in direction (two-target-extension), and (c) one target and immediately back to the start location (two-target-reversal). Unlike manual movements, the movement times for the initial saccade in the two-target-extension condition were not prolonged compared to either of the other two conditions. Moreover, this pattern of results was found for both the shorter and longer amplitude saccades. The results indicate that the OTA does not occur in the oculomotor system and therefore is not a general motor control phenomenon. 相似文献
109.
Behavioral treatment of insomnia in older adults: an open clinical trial comparing two interventions
Pallesen S Nordhus IH Kvale G Nielsen GH Havik OE Johnsen BH Skjøtskift S 《Behaviour research and therapy》2003,41(1):31-48
Fifty-five insomniacs, 60 years or above, participated in a behavioral treatment program, comparing two interventions (sleep hygiene+stimulus control vs sleep hygiene+relaxation tape). Half of the subjects were randomized to a waiting-list condition prior to treatment. No significant changes were observed during the waiting-list period. During the treatment period however, the subjects improved on several sleep parameters, and treatment gains were maintained at a 6-month follow-up. The effects of treatment were greater for nocturnal measures (e.g. sleep onset latency and total sleep time) as compared to daytime measures (e.g. life satisfaction, daytime alertness) and not-targeted behavior (medication use). There were no differences in treatment effects for the two interventions. 相似文献
110.
A 67 item self-report questionnaire called the Meta-Cognitive Beliefs Questionnaire (MCBQ) was developed to assess endorsement of beliefs about the importance of control and negative consequences associated with unwanted, ego-dystonic intrusive thoughts, images and impulses. The MCBQ and a battery of questionnaires that assessed symptoms and cognitions of worry, obsessive-compulsive disorder, anxiety, and depression were administered to large samples of undergraduate students. Beliefs about control of intrusive thoughts and perceived negative consequences due to uncontrolled mental intrusions had a unique significant relationship with obsessions, and to a lesser extent, worry. These findings are consistent with current cognitive behavioral theories that suggest an important role for meta-cognitive beliefs in the pathogenesis of obsessions. 相似文献