CO-56Contractual ObligationMedical Necessity
CO-56 Denial Code: Procedure not proven effective by the payer
The payer classifies the procedure as unproven — a step below 'experimental' denials, driven by the payer's own evidence review.
Why CO-56 happens
- ●Emerging procedure or technology not yet in the payer's coverage policy
- ●Off-guideline use of an otherwise covered service
How to fix a CO-56 denial
- 1
Pull the payer's medical policy cited in the 835 and compare against documentation
- 2
Appeal with peer-reviewed evidence and specialty-society guidelines if coverage criteria are arguably met
- 3
Discuss ABN/waiver status — patient billing depends on notice given before service
How to prevent it
Verify coverage policy for new procedures/technologies before offering them to insured patients.
Drowning in CO-56 denials?
OakClaim works every denial within 48 hours and builds prevention rules so they stop recurring.