Who actually decides whether a hospital buys a clinical AI tool?

Usually nobody, singly. A clinical AI purchase at a health system typically requires alignment across four or five separate reviews: a clinical sponsor who wants it, an informatics review of whether it can be integrated and supported, an information security and privacy review, a financial review of total cost, and increasingly a dedicated AI or algorithm governance review.

Signature authority sits somewhere else again, usually with a system executive or a committee, depending on the dollar amount and whether the money is capital or operating.

The practical consequence is that the person researching a product and the person able to approve it are almost never the same person, and they are looking for different things. See who approves clinical AI in a hospital for the full chain.