Sicker patients may have been given the drug more often the potential reason for bias due to the lack of randomization of the study according to the cnn doctor and described about during the video.
When a medicine is taken frequently, a person may grow tolerant to it. For instance, when morphine or alcohol are used repeatedly, increasing amounts are required to provide the same effect.
Additionally, a medicine only works in certain people and not others due to minute genetic variations. These variations also contribute to the fact that some individuals metabolize medications more quickly than others, which may require them to take larger or lower doses of the same medication to achieve the same effect, depending on their genes.
Read more about bias randomization at
https://brainly.com/question/6701391
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