Course in Laboratory Animal Science for researchers

Experimental Design and Scientific Papers

This subject will be discussed on the last day of the course. It is a great help for the discussion if you have made yourself familiar with the material below in advance:

Study material

• A paper by Crabbe et al. (1999) in the journal Science. The paper may be downloaded here as a pdf-file.
  To read this file you will need the program Adobe Reader which can be downloaded here free of charge, if it is not already installed on your computer.
• Background material. See Reference 4 at the end of the paper. This material is available here on the Internet. Look in particular at the sections entitled "General Public Information", and "Detailed Protocols of the study".

Problems raised by the paper

• What is the main hypothesis in the paper?
• Which experimental design was used for the experiment? Read more about this in the chapter on Design of animal experiments in the compendium which will be handed out on the first day of the course. This chapter may be read here on the Internet.
• How was the number of animals calculated, and why was the calculation performed in this manner?
  Compare the method with the other methods described in the compendium.
  Did the researchers use too few or too many animals?
• Could they have used another design which would have saved animal lives?
  Could they have used another method which would have given clearer statistical results?

  Table 1 in Crabbe's paper provides the basis for the statistical model they used.

Dag Marcus Eide
National Institute of Public Health