The considerations that are actually local, rather than the ones every vendor page repeats.
Patient data does not go in a prompt. Use an agent on the code and keep the data out of it, which is easier when the tool runs on your machine.
Every mainstream AI tool sends your prompt to a model hosted overseas, because there is no New Zealand frontier model to send it to. That is not a reason to avoid them, but it is worth deciding deliberately rather than discovering later. See who is actually building AI here.
A desktop AI agent for Windows, built in Auckland, New Zealand. It reads your files, runs your terminal and drives your browser. Billed per token with a free monthly allowance and no subscription. See pricing, the FAQ, or who builds it.