As such, it is important that statistics are used in medicine in order to justify the development and subsequent use of a particular drug or treatment; as well as identifying in the first place whether it is having the desired effect at all.
At the heart of the use of statistics in medicine is the seemingly insurmountable problem that everybody is different. Not only in a psychological sense, but a physiological sense too. While human beings may share similar organs, tissues and chemical compounds; how they are bonded, how we are composed and the effects different drugs have on the individual can be radically different from one person to the next.
Therefore, to measure the effectiveness of any form of medication, it is important to run trials where a wide variety of subjects are administered the drug. Firstly, this helps gage the effectiveness of the medicine when compared to, for example, a placebo. Subsequent statistical analysis can also give medical professionals and pharmaceutical companies the information they need to judge whether the medicine is an effective treatment for the majority of patients; and whether it is a cost-effective solution to a particular ailment.
Furthermore, once initial studies have been concluded and analyzed statistically, follow up studies can be initiated to investigate the initial statistical findings; providing further evidence as to the effectiveness of any form of treatment.
To briefly summarize; we use statistics in medicine to ensure that the care provided works and is to the benefit of as many people as possible, with as few detrimental affects possible.