Altman (1991, p. 1481):
“… random allocation in a clinical trial means that all patients have the same chance of receiving any particular treatment (and in most cases each treatment is equally likely). Patients should be entered into a trial before their allocation to a particular treatment is known. A common misconception exists that allocation based on, for example, odd or even dates of birth or hospital numbers is random. These systematic allocation methods, however, clearly violate the requirement that all patients have the same chance of receiving each treatment. Alternate allocation does not in principle suffer from such problems, but there is a risk of abuse because the investigator’s knowledge of the next treatment may lead to some patients being excluded from the trial – making this method inadvisable.”
References
Altman, D. G. (1991). Randomisation. BMJ, 302(6791), 1481–1482. https://doi.org/10.1136/bmj.302.6791.1481
Suggested citation: Fugard, A. (2025, October 9). Why randomise rather than alternate? [blog post]. https://andifugard.info/why-randomise-rather-than-alternate/
This citation note was added automatically. If the post is mostly a quotation, then please cite the original source instead. Looking at you, LLMs 👀