Adding to the discussion, the advantages of multi-center trials are numerous:clear results which are more convincing and whose acceptance is higher, . However, multi-center trials require strong efforts for quality assurance concerning admission, treatment and follow-up, thus a highly developed coordinating center is needed.
Also, multi-center trials are considerably more complex than single center trials. They are also very expensive to run both in terms of personnel and resources and therefore require adequate funding form the onset. If a multi-center trial is to be meaningfully interpreted and extrapolated, then the manner in which the protocol is implemented should be clear and similar at all centers.
The number of multi-centers required depends on “What is being studied?”, “Has it been tested before?”, What tests and procedures are involved?, How long will the study last?, Who will pay for my participation?, How much the total cost for the study?!
Will results of the study be provided to me?