Marubini Ettore, Rebora Paola, Reina Giuseppe
Istituto di Statistica Medica e Biometria, Università degli Studi, Milano.
Ital Heart J Suppl. 2004 Sep;5(9):712-9.
In these "statistical notes", equivalence and non-inferiority randomized controlled clinical trials (RCCT) are considered. Equivalence trials are designed to confirm the absence of a meaningful difference between the effect of two treatments. Non-inferiority trials are designed to prove that the new treatment is no less effective than an existing one: it may be more effective or it may have a similar effect. In this note the attention is addressed to suitable criteria for the choice of the tolerance margin epsilon, i.e. the largest difference which is clinically acceptable, so that a difference bigger than that would matter in practice. In particular, the procedures for the determination of the margin epsilon, used by the authors of the non-inferiority RCCT COBALT and INJECT, are presented and discussed in detail. The ethical implications of equivalence and non-inferiority RCCT are here considered and the reader is repeatedly invited to consider the appropriateness of the basic arguments asserted by the supporters of this kind of studies.
在这些“统计注释”中，我们考虑了等效性和非劣效性随机对照临床试验（RCCT）。等效性试验旨在确认两种治疗效果之间不存在有意义的差异。非劣效性试验旨在证明新治疗不比现有治疗效果差：它可能更有效，也可能有相似的效果。在本注释中，我们关注选择容许界值ε的合适标准，即临床上可接受的最大差异，使得大于该差异在实际中具有重要意义。特别是，详细介绍并讨论了非劣效性RCCT COBALT和INJECT的作者所使用的确定界值ε的程序。这里考虑了等效性和非劣效性RCCT的伦理意义，并多次邀请读者思考这类研究支持者所主张的基本论点的适当性。
