Enough people must be taking part to ensure that chance differences and unusual circumstances do not have a decisive effect on the results. Without comparing what happens in similar participants facing similar conditions without getting the new drug, accurate measurement of any observed health changes would not be possible.Ī control group is a key part of large trials. Others factors about the clinical trial could explain the results. The absence of a control group would mean that the researchers could not attribute any improvement or decline in health to the drug or treatment. The purpose of a control group in a randomized controlled trial is to help reduce the likelihood that any benefits or risks that the researchers identify during the trial occur due to factors outside of the experimental treatment. Share on Pinterest An RCT will have a control group to which the researchers will randomly assign people. Randomization removes bias and truly allows for a direct comparison between two groups in a trial, providing a real representation of how the drug will react with the wider population after distribution. Treating different subjects in different ways during the trial reduces the integrity of like-for-like comparisons, giving false results. If the active treatment seems to be producing severe side effects, for example, doctors may try to protect certain types of participant from the drug. Even selection bias with good intentions, such as researchers having concerns about the safety of a drug, is scientifically unsound. Doctors could have a well-intentioned influence over the results. Knowing which participants are getting the experimental drug can result in sound motivations as well as questionable ones. The risk of selection bias may also be high in trials by researchers who have received either direct or indirect funding from a pharmaceutical company looking to prove the efficacy and safety of a new drug.įor this reason, researchers must disclose any potential conflict of interest when conducting a clinical trial, as pharmaceutical manufacturers have a clear financial interest in achieving positive results. On the other hand, if scientists are looking to demonstrate the ineffectiveness or potential danger of a certain treatment, they may assign participants who have a higher risk of complications or a lower chance of success to the group receiving the treatment. This could make a treatment appear more beneficial than it actually is. An RCT gets rid of selection bias by removing the element of choice.įor example, without randomization, scientists may consciously or subconsciously assign patients to the group receiving the active treatment if they look more likely to benefit from the experimental treatment. Scientists refer to this skewing of results as selection bias. Both participants and research scientists can influence results unless the researchers assign participants to groups at random. Randomization prevents the skewing or deliberate manipulation of results. Discussion continues as to whether a product is definitely safe without passing an RCT. However, between 19, 76 applications received approval without undergoing an RCT. The United States Food and Drug Administration (FDA) will generally only approve a new treatment as safe and effective for wider use if results indicate that the effects of the drug are in line with its claims, and if these benefits occur without causing unsafe adverse effects. In the control group, the participants do not receive the new treatment but instead receive a placebo or reference treatment. Controlled: The trial uses a control group for comparison or reference.
0 Comments
Leave a Reply. |