skip to Main Content

Selection Bias: Sequence Generation

Describe the methods used, if any, to generate the allocation sequence to assign experimental animals to groups in sufficient detail to allow an assessment of whether it should produce comparable groups.

Signaling Questions

Did the investigators describe a random component in the sequence generation process such as:

  • Referring to a random number table;
  • Using a computer random number generator.

Examples of a non-random approach:

  • Allocation by judgment or by investigator’s preference;
  • Allocation based on the results of a laboratory test or a series of tests;
  • Allocation by availability of the intervention;
  • Sequence generated by odd or even date of birth;
  • Sequence generated by some rule based on animal number or cage number.
Back To Top