Reduction & Refinement
The R of Reduction includes initiatives that focus on reducing the number of animals used per experiment. This can be achieved, for example, by sharing laboratory animals from 'control groups' or by using 'historical controls'. Furthermore, new statistical analysis methods can calculate exactly how you can get reliable results with as few animals as possible, provided you determine in advance which effect you want to measure. The use of modern measuring instruments, such as an MRI scanner, with which the tumour growth of one laboratory animal can be followed in several stages, instead of using new animals for each stage, can also help to reduce the use of laboratory animals.
The R of Refinement refers to initiatives that focus on everything that can reduce or prevent the 'discomfort' (such as pain) of the laboratory animals, or that can increase the well-being of the animals, before, during and after the experiment. Optimizing housing, reducing boredom or stereotypic behaviour, and applying pain management and humane endpoints are examples of refinement. Although refinement is not an end goal, it is important because it can mean direct, improvements to the lives of laboratory animals in the short term.