OA-186: Level of Care Change Adjustment

What Does OA-186 Mean?

OA-186 is uncommon and typically appears when the level of care adjustment does not fit neatly into the provider's contractual obligation or the patient's responsibility. This may occur in coordination of benefits situations or when the payer is still reviewing the level of care determination.

CARC 186 shows up on your remittance when the payer makes a level of care adjustment — most commonly downgrading the billed service to a lower-acuity level. This is not an outright denial of the service; the payer agrees the patient received care, but disagrees with the intensity or setting that was billed. The result is a reduced payment based on the lower level of care the payer deems appropriate.

This code hits hardest in inpatient and facility settings. A common scenario is billing for inpatient admission when the payer determines that observation status would have been sufficient. It also frequently occurs with E/M levels — billing a level 5 office visit when the payer's review concludes a level 3 or 4 was warranted based on the documentation. Payers typically use clinical criteria tools like InterQual or Milliman to make these determinations, and if the medical record does not meet their thresholds, they will downgrade.

The financial impact can be significant because the gap between the billed level and the approved level often represents a substantial dollar amount. Under CO, the provider must write off this difference. Under PR, the patient's cost-sharing may change based on the adjusted service level. Appeals are common and often successful when the provider can demonstrate that the original level of care was medically necessary with strong clinical documentation.

How to Resolve

Review the clinical documentation against the payer's level of care criteria, and appeal with medical necessity evidence if the original level was justified.

1. Contact the payer Request clarification on why the OA designation was used and when a final determination will be made.
2. Monitor for reclassification The OA adjustment may be reclassified to CO or PR once the payer completes their review. Track the claim status for updates.

How to Prevent OA-186

• Maintain proactive communication with payers during level of care review processes
• Document all interactions with payers regarding level of care determinations

Also Filed As

The same CARC 186 may appear with different Group Codes:

Related Denial Codes