A randomized controlled trial is a type of clinical trial used to test new medical treatments. These trials are considered the most reliable method of gathering data. In fact, pharmaceutical companies must prove that their treatment works in this type of trial before the treatment can be considered credible.
How the Trial Is Structured
As with any scientific experiment, this type of trial is structured with a variable and a control group. The control group doesn’t receive the treatment. The variable group does. Researchers look at how the variable group responds when compared to the control group to determine how well the treatment works.
However, the trial also has a measure to account for the placebo effect.
The placebo effect is the effect by which patients can improve just by believing that they’re being given medication. It can sometimes make ineffective treatments look more effective than they are.
In a randomized controlled trial, the control group and the variable group are selected randomly. The control group is given a placebo treatment, while the variable group is given the real treatment. None of the participants know whether they are receiving a placebo or the real treatment.
To be approved by the FDA, studies need to indicate that a treatment is effective beyond a placebo. Even so, several applications have been approved without doing RCT studies.
How the Randomization Works
The randomization is another important component when collecting objective data. Randomizing the sample prevents researchers from deliberately manipulating or skewing the results by choosing patients with bias. This is called selection bias. By removing the human ability to choose, RCT removes selection bias.
Selection bias can come through in a variety of conscious or subconscious ways:
- Scientists choose patients who seem predisposed to respond well to the treatment, skewing the results more positively.
- Scientists choose patients who are predisposed to complications, skewing the results more negatively.
- Scientists make selections based on funding they have received from the pharmaceutical company or its competitors.
Researchers are required to disclose any funding they have received, as well as any additional conflicts of interest.
By randomizing the test, scientists are able to work with a truly neutral variable and control group.
Standard Treatment Comparisons
Some RCT trials don’t use a placebo in place of the treatment. Instead, they use an established treatment method for the condition. This is called a comparative trial.
In these cases, the control group receives a standardized treatment, and the variable group receives a new treatment. The goal is to determine whether the new treatment has therapeutic benefits beyond those of established treatments.
If there are no benefits beyond established treatments, there isn’t much cause for pharmaceutical companies to market the treatment. But some new treatments may work well for patients who can’t use established treatments for a variety of reasons.
Healthcare providers also use RCTs to obtain results from a diverse group of patients.