Though faecal transplantation for C. difficile has still to undergo a formal clinical trial, with a proper controlgroup, it looks a promising (and cheap) answer to a serious threat.
However, the realization that the more infrequent visit schedule and less intense support for the controlgroup might be limitations of the trial prompted us to amend the protocol in October 2006.
The gold standard for testing medical treatments is the randomized trial, in which patients are randomly assigned to a treatment or controlgroup to spread patient differences evenly and avoid bias in results.