Scientific studies trials

Even listing all above problems and requirements leading to their solution indicates that development of the method of semiconductor chemical sensors opens a wide research domain. In order to resolve this problems and implement all capabilities of the method of semiconductor sensors there are two ways now the old trial and error approach and approach related to further studies of physical and chemical properties of surface phenomena, reactions and processes underlying this method. It is quite clear that the second approach is more promising in order to obtain semiconductor sensors designed for the use in accurate scientific studies and for practical gas analysis. 

In general, the use of placebos in psychopharmacology trials requires additional justification, particularly with very disturbed children. The public health responsibility of publicly funded scientific studies is paramount, and this responsibility implies that only issues of genuine importance be targeted for such studies (Hyman, 1999). There may be times, however, when, for scientific reasons, the use of placebo arms may be ethically justified (Roberts et ah, 2001), in part because there are so few psychopharmacology treatments that... 

In the United States, the National Center of Complementary and Alternative Medicine (NCCAM) was created in 1998 as one of the many research institutes and centers within the prestigious National Institutes of Health (NIH). This government research center collaborates with academic medical centers to evaluate specific nontraditional approaches to health and healing by conducting clinical trials and other scientific studies, as is done for drugs. 

Specific medical claims cannot be made for essential oils or aromatherapy products if such were made, the products would need a product licence. The licence is only granted after an exhaustive series of laboratory and clinical trials to prove safety and efficacy. The issues surrounding research and trials on the use of essential oils in clinical situations are still contentious, but there are increasing numbers of scientific studies and papers in reputable journals. 

The literature is replete with scientific study designs for Phase 1 cancer trials in patients (e.g., see Ref. 10), but such is not the case for first-time-in-human (FTIH)... 

Clinical trial I A scientific study in which physician-researchers study the effects of potential medicines on people usually conducted in three phases (I, II, and III) that determine safety, whether the treatment works, and if it s better than current therapies, respectively. 

It must have undergone rigorous scientific studies and substantial clinical trials to prove its safety and efficacy of action. 

The most typical analytical approach to interpreting the data from scientific studies, including clinical trials, is the statistical significance test, also known as the null hypothesis significance test (NHST). This approach, which has recently come under much scrutiny and debate, formally... 

Currently there are many scientific studies reporting that pharmacological treatment with dimethicone or simethicone reduces gas production and maybe helpful for some infants, although several randomized controlled trials noted no difference in the reduction of colic episodes compared with placebo [41,43,44]. 

Elaborate and varied processes are required to sqiarate the maiqr components of plasms. Although a rational approach to the prindples of fractionation is now possible (see Part III), plasma is such a complex system that the steps of any successful process must be worked out largely by repeated trial, with gradual and systematic variation of the conditions of fractionation. Nevertheless, the motives for persistence in the undertaking are decisive. They fall into two classes (1) The superiority of purified plasma fractions to whole plasma for scientific study. (2) The superiority of the fractions to whole plasma for clinical and other uses (see Cohn, 35, 36, 37, 38). 

The use of chemical inhibitors to decrease the rate of corrosion processes is quite varied. In the oil extraction and processing industries, inhibitors have always been considered to be the first line of defense against corrosion. A great number of scientific studies have been devoted to the subject of corrosion inhibitors. However, most of what is known has grown from trial and error experiments, both in the laboratories and in the field. Rules, equations, and theories to guide inhibitor development or use are very limited. 

A key element in planning and conducting clinical trials is to ensure that they have scientific validity and objectivity. This is particularly relevant with respect to Phase II and III studies, where it is desired to demonstrate a positive benefit to risk outcome. Responses to a drug among a patient population are rarely homogeneous and clear-cut. Thus, sound statistical principles must be applied in order to be able to distinguish significant effects from random events. 

While clearly outlined criteria are essential, a lengthy list of exclusions can also impede subject recruitment. Therefore, a balance must be struck between what is scientifically desirable and that which is still practical with regard to the number of study sites and length of time required to complete the trial. 

The use of multiple study sites can facilitate enrollment and ensure diversity in the study sample. However, as the number of study sites increases, so too does the cost and complexity of managing the trial. Therefore, the proper balance must be struck between issues of cost, logistics, scientific considerations and practicality when deciding on the appropriate number of research sites. 

Clinical trials are costly to conduct, and results are often critical to the commercial viability of a phytochemical product. Seemingly minor decisions, such as which measurement tool to use or a single entry criterion, can produce thousands of dollars in additional costs. Likewise, a great deal of time, effort and money can be saved by having experts review the study protocol to provide feedback regarding ways to improve efficiency, reduce subject burden and insure that the objectives are being met in the most scientifically sound and cost-effective manner possible. In particular, I recommend that an expert statistician is consulted regarding sample size and power and that the assumptions used in these calculations are reviewed carefully with one or more clinicians. It is not uncommon to see two studies with very similar objectives, which vary by two-fold in the number of subjects under study. Often this can be explained by differences in the assumptions employed in the sample size calculations. 

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