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The principles of 3R

​​​​​​​Comparative Medicine strives to continuously and in a broad perspective work with 3R perspectives based on an evidence based foundation. The goal of the 3R office is that an under­standing for the 3R policy shall permeate the work of the whole research community at Karolinska Institutet.


Everyone working with research animals at Karolinska Institutet will have the necessary education to fulfil the vision and share a common set of values.

What is 3R?

The principles of the 3Rs (Replacement, Refinement and Reduction) were developed over 50 years ago by W.M.S. Russell and R.L. Burch, as a framework for humane animal research. Today the 3Rs are increasingly seen as a framework for conducting high quality science in the academic world with more focus on developing alternative approaches which avoid the use of animals. More about alternative methods

  • Replace animal experiments with alternative methods when possible
  • Refine methods and procedures so that pain and discomfort are avoided
  • Reduce the number of animal used

The overall policy at the Karolinska Institutet concerning the 3Rs is that no unnecessary experiment shall be performed and that no animal should be subjected to research if not deemed needed.


The National Committee for the Protection of Animals used for Scientific Purposes/The Swedish 3R-center has now published its Annual report for 2017. Annual Report of the Swedish 3R Center and National committee.

Implementation of the 3R policy aims to

  • Improve and consolidate the culture of care.
  • Evidence-based guidelines and recom­mendations.
  • Evidence-based humane endpoints.
  • An optimized experimental design and development of the statistical evaluation.
  • A full transparency regarding animal experiments.
  • Communicate the value and goal for each animal experiment that has to be performed in relation to the research outcome.
  • Follow up the relevance of each animal ex­periment, that is to compare the research outcome to the animal welfare.
  • Create pre-conditions to improve and standardize husbandry of research animals at KM’s facilities with the aim to promote reduction and refinement.
  • That only animals in good health and with a documented background shall be used in experiments. This will promote reproduc­ibility and reduce the number of animals needed to reach statistical power (refinement).

Ongoing projects

  • LAS (Laboratory Animal Science) Education and Training is a key compo­nent of KM’s 3R program. Quality of work will improve through advancing competence and this will decrease the risk of experi­ments being poorly conducted, ill-designed, variations between experiments over time and unwarranted use of lab animals.
  • Welfare at the holding unit is an important concept of KM. Techinical solutions for monitoring is developed in cooperation with the industry. Refined monitoring gives the opportunity to assess the animals' health status around the clock (refinement).
  • There is also an ongoing project to find solutions to perform animal experiments without taking the animal from its group or its homecage.