The ethics of research involving animals - Nuffield Council on ...

T h e e t h i c s o f r e s e a r c h i n v o l v i n g a n i m a l s
Reduction and Refinement
Introduction
12.1 In the previous chapter we discussed the opportunities and current limitations <strong>of</strong> the first <strong>of</strong>
Russell and Burch’s Three Rs, the Replacement approach. We now turn to the remaining two
concepts Refinement and Reduction, which need to be considered whenever the use <strong>of</strong>
<strong>animals</strong> to achieve a scientific objective is deemed unavoidable. As we have said, the Three
Rs are closely interrelated. 1 <strong>The</strong> relationship between Reduction and Refinement is
particularly evident when these principles are applied at the early stage <strong>of</strong> <strong>research</strong> projects
to improve <strong>research</strong> strategy as a whole. We first give brief consideration to this relationship
and then examine Reduction and Refinement more closely as individual concepts. <strong>The</strong> role
<strong>of</strong> harmonising international test guidelines for the purpose <strong>of</strong> reducing animal <strong>research</strong> is
then explored before we focus on the potential <strong>of</strong> Refinements. We give examples <strong>of</strong> how
to implement Refinements in specific areas <strong>of</strong> <strong>research</strong> and also consider possible barriers.
Applying Reduction and Refinement to <strong>research</strong> strategies
12.2 Animals will suffer needlessly if they are used in <strong>research</strong> where scientific methodology is
poor. In such cases, <strong>research</strong> does not achieve its scientific objectives, and fails to generate
significant knowledge. It is for this reason that the application <strong>of</strong> the Three Rs should begin
with a careful assessment <strong>of</strong> the initial experimental design and be continued throughout
the duration <strong>of</strong> each and every <strong>research</strong> project. This process requires a number <strong>of</strong> basic
questions to be addressed at a very early stage. For example, is the chosen animal model
sufficiently relevant to the scientific question being asked or health problem under study?
Is there a genuine scientific basis for using a particular animal model? Could the scientific
question itself be refined? Could the scientific objective <strong>of</strong> the work be modified to avoid
the use <strong>of</strong> an animal model? <strong>The</strong> following three general approaches are relevant to the
successful implementation <strong>of</strong> Reduction and Refinement at this stage <strong>of</strong> <strong>research</strong>.
CHAPTER 12 REDUCTION AND REFINEMENT
■ Background <strong>research</strong>: it is essential that a thorough search <strong>of</strong> the published literature is
undertaken to ensure that the proposed experiments have not already been undertaken
and the objectives <strong>of</strong> the <strong>research</strong> have not already been met by previous well-conducted
experiments. Part <strong>of</strong> this survey <strong>of</strong> the literature should be an assessment <strong>of</strong> the validity
<strong>of</strong> the conclusions <strong>of</strong> previous studies. New experiments should not be based on unsound
conclusions drawn from poorly designed experiments.
■ A staged approach: before embarking on large or complex experiments the project
should be broken down into a series <strong>of</strong> pilot experiments, with defined decision points
that inform the transition from one stage to another. A small pilot experiment on
<strong>animals</strong> or in vitro <strong>research</strong> can be very useful in guiding the design <strong>of</strong> subsequent, larger
experiments. For example, an initial pilot study might help define experimental
parameters early on, so that fewer <strong>animals</strong> could be used later. It might also be possible
to refine experiments so that suffering and the number <strong>of</strong> <strong>animals</strong> used is reduced by
carrying out pilot experiments on anaesthetised <strong>animals</strong> that are not allowed to recover.
■ Teamwork and resources: the successful completion <strong>of</strong> an experiment depends on many
factors, including the skills and performance <strong>of</strong> the staff involved, and the availability <strong>of</strong>
suitable equipment and facilities. Optimal experimental design and successful application
<strong>of</strong> the Three Rs requires a multidisciplinary approach with contributions from biomedical
1 Russell and Burch themselves acknowledged that there was overlap between the Three Rs; see Russell WMS and Burch RL (1959)
<strong>The</strong> Principles <strong>of</strong> Humane Experimental Technique (London: Methuen).
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