Editing Randomized controlled trial (section)

==== Adaptive ====
At least two types of "adaptive" randomization procedures have been used in RCTs, but much less frequently than simple or restricted randomization:
* Covariate-adaptive randomization, of which one type is [[Minimisation (clinical trials)|minimization]]: The probability of being assigned to a group varies in order to minimize "covariate imbalance."<ref name="Lachin-1988b" /> Minimization is reported to have "supporters and detractors"<ref name="Schulz-2002" /> because only the first subject's group assignment is truly chosen at random, the method does not necessarily eliminate bias on unknown factors.<ref name="Moher-2010" />
* Response-adaptive randomization, also known as outcome-adaptive randomization: The probability of being assigned to a group increases if the responses of the prior patients in the group were favorable.<ref name="Lachin-1988b" /> Although arguments have been made that this approach is more ethical than other types of randomization when the probability that a treatment is effective or ineffective increases during the course of an RCT, ethicists have not yet studied the approach in detail.<ref name="Rosenberger-1993">{{Cite journal |vauthors=Rosenberger WF, Lachin JM |date=December 1993 |title=The use of response-adaptive designs in clinical trials |journal=Controlled Clinical Trials |volume=14 |issue=6 |pages=471–484 |doi=10.1016/0197-2456(93)90028-C |pmid=8119063}}</ref>