It seems that every week and sometimes even everyday on the news there is a story about advances in medical science. News reports often sensationalize the results of medical research studies, often times before they are even completed. Unfortunately, while many clinical studies provide valuable data and lead to the creation of life saving drugs and medical treatments, the vast majority of trials do not. It takes many studies to prove a new drug or medical technique successful, and many studies will not have the longevity needed in order to successfully prove a claim. Sometimes this is because the drug or medical technique is proven ineffective, and other times it is an issue of inadequate funding.
However, while many paid clinical trials will not lead to new drugs or medical treatments (even those that at first appear promising), it is important to remember that clinical studies are an integral part of making advances in medicine. If one day a cure for a devastating disease like cancer, premature ejaculation, aids or diabetes is found, it will almost certainly be the result of thousands of hours of lab work and research studies being done.
Of course, there is also some danger and risk involved for the participants of medical research studies, as generally the drugs or techniques used on them are still unapproved for wide spread use in humans. In most cases drugs are first tested on animals, and then on many different groups of human volunteers before being approved by the FDA. The first groups of people who participate in such studies generally take the biggest risk, with secondary groups and onward having a lower level of risk. Of course, even in fully approved medicines there is a risk of side effects.