An SCA applies to a single patient and allows an out-of-network provider to be treated as in-network for that patient, while a procedure authorization is a check on a specific medical procedure for a patient, regardless of provider network status.
Purpose:
An SCA is used when a patient wants to see a specific out-of-network provider and the insurance company agrees to cover the treatment at a negotiated rate, whereas a procedure authorization is used to ensure that the insurance company will cover a particular medical service.
Negotiation:
An SCA often involves negotiating payment terms between the insurance company and the out-of-network provider specifically for that patient, whereas a procedure authorization usually only requires the provider to demonstrate medical necessity for the procedure.