Ambulance Service, A0428: BLS, Nonemergency Transport, All Modifiers - Final Results of Service Specific Prepayment Review Northern California

In order to fulfill our contractual obligation with the CMS, Noridian Healthcare Solutions, LLC, performs prepayment claim review in accordance with CMS Internet Only Manual (IOM), Publication 100-08, Medicare Program Integrity Manual, Chapter 3.

This article is to update providers of the quarterly edit effectiveness results of a Service Specific Targeted Review on claims for the following procedure code(s):

  • HCPCS ® A0428 – Ambulance service, basic life support, nonemergency transport, (BLS) with all modifier combinations.

Summary of Findings

Findings of claims reviewed from March 3, 2017 through June 1, 2017 are as follows:

  • 1,213 Claims Reviewed
  • 66 Claims Paid
  • 1,147 Claims Corrected or Denied
  • 92.21% Error Rate

The error rate is calculated by dividing the dollar amount of charges billed in error (minus any confirmed under-billed charges) by the total amount of charges for services medically reviewed.

If providers disagree with a claim determination, the normal Appeal process may be followed as directed in your claim Remittance Advice (RA).

Going Forward

Based on the results of this review, Noridian will discontinue with the Prepayment Service Specific Review.

Top Denial Reasons

Noridian is only required to give a high-level determination of the claims reviewed. Individual claim determinations can be found on your Remittance Advice (RA). If you have any questions, contact the Provider Contact Center.

Could safely travel by other means

  • The documentation returned did not support the reasonable necessity of the service as the beneficiary could have safely traveled by other means.

Failure to submit documentation

  • Documentation was not submitted to support the claims submitted to Medicare by the time frame indicated in the Automated Development Letter (ADS). If documentation is not received by Noridian by day 45, the claim will automatically deny. The time frame for submission of documentation is detailed in the ADS letter. Noridian MR cannot give extensions for submitting documentation. Submit documentation to support services billed to Medicare. Failure to submit documentation results in a denial of the claim.

Insufficient Documentation

  • The service was denied because the documentation submitted failed to contain identifiable information. Ensure the submitted documentation contains the correct date of service, Beneficiary, rendering provider and service.

Educational Resources and References

The CMS regulations related to this service are available at:

Noridian references are available at:

Additional information, educational opportunities and training tools related to this service are available on our Education and Outreach page.

Last Updated Jun 06 , 2025