CPT code
Test administration by a professional, each added 30 minutes
In the order to send them
Why these codes
Testing by a psychologist or under one: mental health, then outpatient provider.
If a payer returns nothing
Payers don't all answer every service type. Send 30 (Health Benefit Plan Coverage) for the plan's general benefits.
Sources
X12 HIPAA 5010 service type code definitions; VerifyTX billing practice