Research study in which the same research procedures are performed at multiple sites. There is often a lead institution that is the prime recipient of the funding for the overall study and that may be responsible for administrative oversight of the overall study. Typically, the prime recipient establishes sub-contracts with the performance sites. Each site must have local Institutional Review Board (IRB) approval, or must rely on another IRB. A single IRB can be used to provide review for many or all of the sites.