What is a randomized controlled experiment

Randomized controlled study

English: randomized controlled trial, RCT

1 definition

A randomized controlled trial, short RCT, is a study design for experimental studies that, due to its properties, is considered the "gold standard" of a study design.

2 properties

2.1 "controlled"

The randomized controlled trial is called "controlled" because there is both an experimental group and an experimental group Control group gives. The intervention is carried out on the members of the experimental group (verum group), whereas the members of the control group receive e.g. a sham intervention (placebo), a current standard therapy, or can also remain untreated.[1] In comparison to sham therapy or non-treatment, differences between the two groups in terms of the effect can be directly attributed to the tested intervention. When comparing with a standard therapy already recognized as effective, the effectiveness is shown by equivalence or superiority compared to the control group.

2.2 "randomized"

The randomized controlled study is called "randomized" because the subjects are assigned to the experimental or control group coincidentally he follows. This ensures that both groups are largely equivalent to one another in terms of their composition.

3 Other properties

Randomized controlled trials are usually double-blinded, i. H. Neither the test person himself nor the investigator know whether the test person belongs to the experimental or control group. This prevents distortion effects that arise either from the test person (placebo effect, Hawthorne effect) or from the investigator (Rosenthal effect).

4 sources

  1. ↑ http: //www.evimed.ch/glossar/random_kontrollierte.html