controlled study
nounUK /kənˈtrəʊld ˈstʌdi/
US /kənˈtroʊld ˈstʌdi/
A controlled study is a test where scientists compare two groups to see what really works.
The doctors did a controlled study to find out if the new medicine helped people feel better.
OTHER MEANINGS
2. A research method where one factor is changed while everything else stays the same.
In the controlled study, only the amount of water given to the plants was different.
3. A fair test used to check whether a treatment causes a real effect.
The controlled study showed that the vitamin did not change how often people got sick.
4. A scientific comparison between a group that gets a treatment and a group that does not.
The controlled study compared children who read every day with children who did not.