The harm-benefit analysis determines whether or not an animal experiment may be authorised and conducted. During the process, the gain in knowledge expected is compared with the anticipated level of distress suffered by the animal.
According to article 24 of the Animal Experimentation Ordinance, the constraint suffered by animals caused by interventions or measures taken as part of animal experiments is divided into four constraint categories. Ultimately, the purpose is to assess whether the gain in knowledge justifies the constraint suffered by the animals. The expected benefits to society brought about by animal experiments must be greater than the suffering of the animals or the violation of their dignity.
Degrees of severity as a way to measure constraint
Degree of severity 0
No constraint, e.g. observational studies:
Interventions and handling of animals for experimental purposes which do not subject the animals to any pain, suffering or injury, do not cause them to suffer fear and do not impair their general state of health;
Almost half of all laboratory animals are used in experiments in which they are only subjected to degree of severity 0.
Degree of severity 1
Interventions and handling of animals for experimental purposes which cause slight pain or injury or slight impairment of their general state of health;
Degree of severity 2
Interventions and handling of animals for experimental purposes which cause short-term moderate or medium- to long-term slight pain, suffering or injury, short-term moderate fear or short to medium-term severe impairment of their general state of health.
Degree of severity 3
severe constraint, e.g. transplanting aggressive tumours in animals
Interventions and handling of animals for experimental purposes which cause medium to long-term moderate pain or severe pain, long-term moderate to severe suffering, medium- to long-term moderate injury or severe injury, long-term severe fear or severe impairment of their general state of health.
Humane endpoints can also be decisive for limiting the degree of severity: The researchers must specify precisely the levels of constraint or results which require an animal experiment to be aborted.
In order to conduct a harm-benefit analysis, the interests, benefits and objectives of all parties concerned must be specified, assessed, weighed up and finally compared with each other. The result of this harm-benefit analysis represents an informed judgement of whether the constraint suffered by the animal (suffering, pain, fear and injury) can be justified or not. This can be decided on a case-by-case basis or possibly, for a specific category of cases.
The benefits to society can vary greatly: new medicines, verification of non-toxicity of a substance, gain of scientific knowledge, better husbandry conditions for animals and much more. In applied research, the benefits are often obvious.
However, in basic research it is often very difficult to demonstrate a direct benefit. Nevertheless, it is particularly in this type of research that the benefits prove to be greatest in the long term.
It is primarily up to the researcher himself to convincingly show the benefits that his work could bring.
On its website, the ethics committee of the Swiss Academy of Sciences (SCNAT) provides a template for self-testing the ethical harm-benefit analysis during animal experiments.
Last modification 11.08.2020