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11.
Donald B. Penzien PhD ; Frank Andrasik PhD ; Brian M. Freidenberg PhD ; Timothy T. Houle PhD ; Alvin E. Lake III PhD; Gay L. Lipchik PhD ; Kenneth A. Holroyd PhD ; Richard B. Lipton MD ; Douglas C. McCrory MD ; Justin M. Nash PhD ; Robert A. Nicholson PhD ; Scott W. Powers PhD ABPP ; Jeanetta C. Rains PhD ; David A. Wittrock PhD 《Headache》2005,45(S2):S110-S132
Guidelines for design of clinical trials evaluating behavioral headache treatments were developed to facilitate production of quality research evaluating behavioral therapies for management of primary headache disorders. These guidelines were produced by a Workgroup of headache researchers under auspices of the American Headache Society. The guidelines are complementary to and modeled after guidelines for pharmacological trials published by the International Headache Society, but they address methodologic considerations unique to behavioral and other nonpharmacological treatments. Explicit guidelines for evaluating behavioral headache therapies are needed as the optimal methodology for behavioral (and other nonpharmacologic) trials necessarily differs from the preferred methodology for drug trials. In addition, trials comparing and integrating drug and behavioral therapies present methodological challenges not addressed by guidelines for pharmacologic research. These guidelines address patient selection, trial design for behavioral treatments and for comparisons across multiple treatment modalities (eg, behavioral vs pharmacologic), evaluation of results, and research ethics. Although developed specifically for behavioral therapies, the guidelines may apply to the design of clinical trials evaluating many forms of nonpharmacologic therapies for headache. 相似文献
12.
This article identifies common characteristics of educationally related programs that form a common basis for understanding and working with gifted programs. Special approaches and programs for educational enrichment as well as specific activities that have been successful are discussed. 相似文献
13.
Researchers usually employ orthogonal arrays or D-optimal designs with little or no attribute overlap in stated-choice surveys. The challenge is to balance statistical efficiency and respondent burden to minimize the overall error in the survey responses. This study examined whether simplifying the choice task, by using a design with more overlap, provides advantages over standard minimum-overlap methods. We administered two designs for eliciting HIV test preferences to split samples. Surveys were undertaken at four HIV testing locations in San Francisco, California. Personal characteristics had different effects on willingness to pay for the two treatments, and gains in statistical efficiency in the minimal-overlap version more than compensated for possible imprecision from increased measurement error. 相似文献
14.
周英华 《中华医学教育杂志》2006,26(2):31-32
本文以“健康与疾病”为例,介绍了成人护理专科的护理学基础课堂教学设计。主要包括学生的情况分析、授课计划的制定、教学方法的选择、课程内容的优化、教学媒体和教学案例的运用等。同时,提出了调动学生的学习积极性、学生终身学习意识教育及医德教育等问题,从而使学生既能真正获得有用知识,又尽可能地通过考试取得学历文凭。 相似文献
15.
Sajeel Chowdhary MD Lisa M. Chalmers PA-C Marc Chamberlain MD 《Journal of neuroimaging》2007,17(1):69-73
In the course of 1 year at a tertiary cancer center, 3 patients (2 men; 1 woman; age 51-75 years) were seen in neurological consultation (1.5% of all consultations). Clinical course in all patients was of a progressive neurologic disorder not consistent with either a primary or secondary malignancy. Magnetic resonance (MR) imaging was most informative with respect to diagnosis and subsequent management. Brain biopsy was performed in all patients to assist in both diagnosis and prognostication. All patients were determined to have progressive multifocal leukoencephalopathy (PML) by brain biopsy. 相似文献
16.
Albert Kingman 《Journal of periodontal research》1992,27(4):378-389
Simulation studies were conducted to address specific statistical issues which arise in the design and analysis of gingivitis studies whose principal aim is the demonstration of superiority or equivalence of one product to another. The effects of measurement scale, using differences or ratios of group means, particular statistical test produces and specific rules demonstrating superiority or equivalence were investigated. An alternative concept to equivalence—denoted “least as good”—was also defined and evaluated. For a wide class of possible distributions of gingivitis scores, characterized by specific gamma distributions, the student-t test applied to means of subject GI gingivitis scores proved to be the most powerful of the test produces considered, having statistical properties quite similar to the randomization or permutation test procedure. Transformations of subject GI mean gingivitis scores did not produce an advantage in demonstrating either superiority or equivalence, and in some cases made it more difficult. Little difference was observed in test results when using the difference in group means as compared with using the ratio of group means for demonstrating either equivalence or superiority. The clinically significant rule produced the lowest false-positive rates for products slightly better than the active control, and similar false-positive and -negative rates as the statistically significant rule for products clearly superior to the active control. Demonstration of product equivalence will require more subjects per group than demonstrating product superiority, the size of this difference being a function of the definition of superiority that is accepted. Showing that the 90% confidence interval for 100*R is completely contained within the [90%, 110%] interval is the preferred method of demonstrating equivalence today, although much more research needs to be done to improve methods for demonstrating product equivalence. The “least as good” alternative to “equivalence” makes it easier to demonstrate “equivalence” for products slightly better than the active control product, but both experience great difficulty in demonstrating equivalence for lest products not quite as good as the active control. 相似文献
17.
STEVEN N. VASLEF LYLE F. MOCKROS KEITH E. COOK RONALD J. LEONARD JEFFREY C. SUNG ROBERT W. ANDERSON 《Artificial organs》1994,18(11):813-817
Abstract: A semiempirical mathematical model of convective oxygen transport is used to design a new, low pressure loss, implantable artificial lung that could be used as a bridge to lung transplantation in patients with advanced respiratory failure. The mass transfer and flow friction relations pertinent to the design of a cross–flow hollow fiber membrane lung are described. The artificial lung is designed to transfer over 200 ml/min of oxygen at blood flow rates up to 5 L/min. A compact design and a blood-side pressure loss of <15 mm Hg allows the device to be implanted in the left chest without the need for a prosthetic blood pump. Surgical implantation of the artificial lung would require the creation of inflow and outflow anastomoses. Oxygen would be supplied via an external source. Blood properties, operating conditions, and empirically determined mass transfer and flow properties are all specified and input into a computer program that numerically solves the design equations. Computer–generated values for the device frontal area, blood path length, and fiber surface area are thereby obtained. The use of this computer–assisted design minimizes the need for extensive trial–and–error testing of prototype devices. Results from in vitro tests of a prototype implantable lung indicate that the mathematical model we describe is an accurate and useful tool in the design of hollow fiber artificial lungs. 相似文献
18.
Herman M. van Praag 《European neuropsychopharmacology》1992,2(4):393-404
5-HT disturbances in depression (as exemplified by lowered CSF 5-HIAA) are not syndrome specific but related to components of the depressive syndrome, specifically to increased anxiety and aggression. These 5-HT disturbances are probably core pathogenetic processes not derivative features. I hypothesized that in this subtype of depression, i.e. in “5-HT related depression”, the key psychopathological disturbances are dysregulation of anxiety and aggression, while mood lowering is a “by-product”. Based on this hypothesis it was predicted that agents which ameliorate anxiety and/or aggression via harmonization of 5-HTergic transmission will, in addition, exert overall antidepressant effect in “5-HT related depression”. The study of the relative “weight” of the various psychopathological components of depression is a basic exercise in understanding the nature of that condition and could, as such, greatly facilitate the goal-directed search for new and innovative antidepressants. 相似文献
19.
We describe how adverse drug reactions (ADRs) can play an important role in pharmaceutical research and drug development. Not only do ADRs represent the risks and drawbacks associated with drugs but they can also be related to other knowledge available in pharmaceutical and medical research. We offer a model that can be used to systematically map the pathways through which ADRs can lead to innovative research. These pathways include chemical, therapeutic or pathophysiological steps that can be taken to arrive at new knowledge based on ADRs. We used the development of angiotensin-converting enzyme inhibitors, especially captopril, as a case study. The similarity between the ADR profiles of captopril and penicillamine was a starting point for further innovation. Historical analysis shows that in several instances research in the field of angiotensin-converting enzyme inhibitors has been triggered by ADRs. The model presented here might be applicable to other areas of innovative drug research. 相似文献
20.