Study Design: Randomized Controlled Trials
- Randomized Controlled Trials
Randomized controlled trials, or RCTs, are considered the gold standard of clinical research.
In this type of study design, patients are randomly assigned to one of two groups, an experimental and a control group.
The experimental group receives the treatment under investigation while the control group receives the standard “default” treatment
(i.e. sugar pill placebo). Assigning patients at random reduces the risk of selection bias and increases the probability that the
differences in outcomes between the groups can be attributed to the intervention being tested.
Randomization prevents other biases and allows for a more definitive interpretation of results.
However, RCTs are difficult to design, as they typically require the support of specialized methodologists. They are also time-consuming to implement
and complete. This poses a certain problem for academic physicians who are often under pressure to publish. As a result, these
physicians may not wish to undergo the time consuming process to conduct RCTs.
In addition, RCTs require a large sample size, and thus are expensive to conduct. They are also susceptible to the "moving target" problem.
With technologies that are fast moving such as many diagnostic imaging technologies, the time required to complete a randomized trial may render the results obsolete
or at the very least less valuable.
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