Former Federal Reserve chairman Ben Bernanke said Wednesday that the size of a financial firm is only one factor in determining whether it has reached too-big-to-fail status.

Mr. Bernanke argued at an event at the Brookings Institution that a lot of factors come into play when regulators try to determine if a firm has reached a status where its failure would threaten the functioning of the financial system. Too-big-to-fail firms played a starring role in fueling the financial crisis, and while there’s been a huge push by regulatory authorities to reduce ongoing risks, almost all agree the process is not yet complete.