An increasing number of drugs removed from the market because of unacceptable toxicity raises concerns regarding preapproval
testing of drug safety. In the present paper it is postulated that the non-inferiority type of trial should be abandoned in
favor of the superiority trial with active controls and less stringent (p<0.1, both for efficacy and toxicity) statistics.
This approach will increase sensitivity of detection of drug-induced adverse effects at the expense of increasing false positive
results regarding the difference in efficacy between the tested and reference drug. Such a move will increase the protection
of future patients. In addition, the proposed design is far more acceptable from the clinical (e.g. no need to specify the
statistically expected “unimportant” number of deaths) and ethical points of view, as well as being favored by the strong
incentive of involved parties. In the second part of this paper arguments are presented in favor of the hypothesis that placebo
(still used in some superiority trials) does not induce adverse effects. The assertion that placebo may induce adverse effects
is probably biased by the nature of the clinical experiment. Such a conclusion is supported by studies indicating that placebo-induced
adverse effects are disease — and treatment — specific. The modification of clinical trials according to the proposed changes
may increase the trials’ sensitivity at detecting adverse effects of drugs.
A lecture on the subject of this paper was presented at the 6th International Bioethics Conference on the subject of ‘The
Responsible Conduct of Basic and Clinical Research’, held in Warsaw, Poland, 3–4 June 2005. 相似文献
The first part of the paper is a reminder of fundamental results connected with the adequacy problem for sentential logics with respect to matrix semantics. One of the main notions associated with the problem, namely that of the degree of complexity of a sentential logic, is elucidated by a couple of examples in the second part of the paper. E.g., it is shown that the minimal logic of Johansson and some of its extensions have degree of complexity 2. This is the first example of an exact estimation of the degree of natural complex logics, i.e. logics whose deducibility relation cannot be represented by a single matrix. The remaining examples of complex logics are more artificial, having been constructed for the purpose of checking some theoretical possibilities.The paper was presented to the Polish Philosophical Society, Wrocaw Branch, at its meeting on March 27th, 1980.The authors wish to thank both the referees of Studia Logica for their helpful and very insightful remarks. Following their criticism, we have been able to improve the style and structure of our presentation. In particular, we are indebted to the referees for pointing out a gap in the original proof of Theorem 2, and we have incorporated into the revised text a corrected proof of step (2.1) which one of them was kind enough to supply in detail. 相似文献
In this paper being a sequel to our [1] the logic with semi-negation is chosen as an example to elucidate some basic notions of the semantics for sentential calculi. E.g., there are shown some links between the Post number and the degree of complexity of a sentential logic, and it is proved that the degree of complexity of the sentential logic with semi-negation is 20. This is the first known example of a logic with such a degree of complexity. The results of the final part of the paper cast a new light on the scope of the Kripke-style semantics in comparison to the matrix semantics.In memory of Roman Suszko 相似文献
The purpose of the paper is to rethink the role of actuality in the branching model of possibilities. We investigate the idea that the model should be enriched with an additional factor—the so-called Thin Red Line—which is supposed to represent the single possible course of events that gets actualized in time. We believe that this idea was often misconceived which prompted some unfortunate reactions. On the one hand, it suggested problematic semantic models of future tense and and on the other, it provoked questionable lines of criticism. We reassess the debate and point to potential pitfalls, focusing on the semantic dimension of the Thin Red Line theory. Our agenda transcends the semantics, however. We conclude that semantic considerations do not threaten the Thin Red Line theory and that the proper debate should be carried in the domain of metaphysics.
We show that Euclidean geometry in suitably high dimension can be expressed as a theory of orthogonality of subspaces with fixed dimensions and fixed dimension of their meet. 相似文献
This paper is a study of similarities and differences between strong and weak quantum consequence operations determined by a given class of ortholattices. We prove that the only strong orthologics which admits the deduction theorem (the only strong orthologics with algebraic semantics, the only equivalential strong orthologics, respectively) is the classical logic. 相似文献
In this paper we investigate some basic semantic and syntactic conditions characterizing the equivalence connective. In particular we define three basic classes of algebras: the class of weak equivalential algebras, the class of equivalential algebras and the class of regular equivalential algebras (see [12]).Weak equivalential algebras can be used to study purely equivalential fragments of relevant logics and strict equivalential fragments of some modal logics (for investigations of strict implicational fragments of modal logics see [20]). Equivalential algebras are suitable to study purely equivalential fragment of BCI and BCK logic (see [21], p. 316). A subclass of the class of regular equivalential algebras is suitable to study equivalential fragments of ukasiewicz logics. Some subvarieties of the class of regular equivalential algebras provide natural semantics for equivalential fragments of the intuitionistic prepositional logic and various intermediate logics (see [13]).The last chapter is a selection of research problems which in the author's opinion are worth to be solved. 相似文献
Animal Cognition - The efficiency of aposematic colouration of prey is based on the innate bias or facilitation of avoidance learning of predators. In many toxic bufonids, larvae are uniformly... 相似文献