Collaborating institutions in multi-site research must have a federalwide assurance. Investigators must provide documentation of IRB approval or an IRB Authorization Agreement [1] for collaborators. The roles and responsibilities of each institution must be specified in any such Agreement, along with a statement by which the parties agree to comply with any special DoD requirements.
Links:
[1] https://hso.research.uiowa.edu/b-multi-center-studies-0