Glossary - R

Randomised controlled trial

When referring to clinical trials, randomised refers to a trial which is set up in a deliberately random or unpredictable way. Known as the gold standard of clinical trials, randomised controlled trials ensure that the participants in the study are allocated randomly to the study groups.


The rectum is the space between the colon and the anus, where faeces are stored before bowel movements.


Belonging to the Clostridia class, this genus of bacteria is found in the human digestive tract and ferments ingested plant material.