“Single IRB” vs “Central IRB” – What’s the Difference?

In 2016, the NIH policy on IRB review for multisite research brought a new-ish term into the clinical research lexicon: “single IRB review,” or “sIRB review.” This term seems to be on its way to replacing “central IRB” or “cIRB” in discussions about one IRB review conducted on behalf of all (or most) participating sites in a multicenter study.

What’s going on here—is sIRB a new term? Is there a difference between sIRB and cIRB review?

As far as we can tell, “single IRB review” and “central IRB review” mean the same thing: a single IRB of record overseeing all clinical trial sites participating in a multisite study.

The reasoning behind these different IRB terms may depend on who is using them, and their physical proximity to the IRB in question. Entities that do not have internal IRBs, like a pharma company or a CRO, may refer to an IRB as a “central IRB” or “single IRB” or “local IRB.” An institution would most likely refer to anything other than their local IRB as an “external” IRB (potentially encompassing both independent IRBs as well as IRBs at other institutions).

While we don’t know for sure, it’s possible that NIH chose “single IRB” because “central IRB” has developed connotations of “independence” from a specific institution—for example, Advarra is an independent commercial IRB, and NCI’s CIRB is an independent federal IRB. In the NIH policy, a designated “single IRB” may be either completely independent OR associated with an institution.

Ultimately, none of these terms are entirely precise. To be clear, when you’re talking about the IRB overseeing participant protections for a given study, you’re talking about the “IRB of record.” This is the term we see most consistently in federal agency guidances, correspondence and other documentation. In using the term “IRB of record,” we focus on the IRB’s responsibilities, which are much more important than the IRB’s arbitrary location or organizational relationship.

It is likely we’ll be seeing a lot more “single IRB” and “sIRB” usages elbowing “central IRB” and “cIRB” out of our shared vocabulary. No matter what you call it, it’s clear that centralized IRB review of multisite clinical research is here to stay. However, whether you’re working with a sIRB, cIRB or local IRB, just be sure you’re clear on the responsibilities assigned to the IRB of record and the responsibilities retained by individual sites.

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