Festing M F
MRC Toxicology Unit, University of Leicester, UK.
Exp Gerontol. 1997 Jan-Apr;32(1-2):39-47. doi: 10.1016/s0531-5565(96)00032-0.
Rodent gerontology experiments should be carefully designed and correctly analyzed so as to provide the maximum amount of information for the minimum amount of work. There are five criteria for a "good" experimental design. These are applicable both to in vivo and in vitro experiments: (1) The experiment should be unbiased so that it is possible to make a true comparison between treatment groups in the knowledge that no one group has a more favorable "environment." (2) The experiment should have high precision so that if there is a true treatment effect there will be a good chance of detecting it. This is obtained by selecting uniform material such as isogenic strains, which are free of pathogenic microorganisms, and by using randomized block experimental designs. It can also be increased by increasing the number of observations. However, increasing the size of the experiment beyond a certain point will only marginally increase precision. (3) The experiment should have a wide range of applicability so it should be designed to explore the sensitivity of the observed experimental treatment effect to other variables such as the strain, sex, diet, husbandry, and age of the animals. With in vitro data, variables such as media composition and incubation times may also be important. The importance of such variables can often be evaluated efficiently using "factorial" experimental designs, without any substantial increase in the overall number of animals. (4) The experiment should be simple so that there is little chance of groups becoming muddled. Generally, formal experimental designs that are planned before the work starts should be used. (5) The experiment should provide the ability to calculate uncertainty. In other words, it should be capable of being statistically analyzed so that the level of confidence in the results can be quantified.
啮齿动物老年学实验应精心设计并正确分析，以便用最少的工作量提供最大量的信息。“良好”的实验设计有五条标准。这些标准适用于体内和体外实验：（1）实验应无偏倚，以便在知道没有一组具有更有利“环境”的情况下，能够在各治疗组之间进行真实比较。（2）实验应具有高精度，以便如果存在真正的治疗效果，就有很大机会检测到它。这可通过选择均匀的材料，如无致病微生物的同基因品系，并采用随机区组实验设计来实现。也可以通过增加观察次数来提高精度。然而，将实验规模扩大到一定程度以上只会略微提高精度。（3）实验应具有广泛的适用性，因此应设计用于探索观察到的实验治疗效果对其他变量的敏感性，如动物的品系、性别、饮食、饲养条件和年龄。对于体外数据，培养基成分和孵育时间等变量也可能很重要。使用“析因”实验设计通常可以有效地评估这些变量的重要性，而不会大幅增加动物总数。（4）实验应简单，以便各组混淆的可能性很小。一般来说，应使用工作开始前计划好的正式实验设计。（5）实验应具备计算不确定性的能力。换句话说，它应该能够进行统计分析，以便对结果的置信水平进行量化。
