Notes on designing an experiment

Justification for the design

For a simple design, you need to justify the amount of replication.

  • If there is too much replication then the experiment may waste time and money. If animals are to be sacrificed, it is unethical to use too many.
  • If there is too little replication then any genuine differences between treatments may be masked by the differences among the experimental units. An experiment which is too small to give any conclusions is also a waste of resources. It is also an unethical use of animals or people.

    More details should be given to justify more complex designs.

    protocol purpose treatments experimental units method observational units
    measurements design justification randomization plan analysis

    Page maintained by R. A. Bailey

    Page updated 17/11/01