control group
"In a nutshell, this means that there is a control group of identical patients that does not receive the treatment of interest. The control group is like the study group in every other measurable way that might be relevant, such as average age, coexisting diagnoses, average weight, fraction that smoke, etc."
"The bottom line: the control group is like the treatment group. By contrast, with poorly-controlled studies, ineligible patients may be used as controls. Moreover, even if controls are selected among those eli-
gible for surgery, the surgeon may choose to operate only on the healthier patients while sicker patients are put in the control group "
METAMIA is a free database of analogy and metaphor. Anyone can contribute or search. The subject matter can be anything. Science is popular, but poetry is encouraged. The goal is to integrate our fluid muses with the stark literalism of a relational database. Metamia is like a girdle for your muses, a cognitive girdle.