Prior Authorization, ABNs and Financial Policies

Prior Authorization, Precertification, and Predetermination

In an outpatient clinic, administrative processes ensure that services ordered by the provider align with payer guidelines before patient care is delivered. Precertification is a payer review before a planned service; payers may use the terms precertification and prior authorization interchangeably, so staff should follow the specific plan's requirements. Precertification is distinct from eligibility and benefit verification: eligibility confirms enrollment, while benefit verification may also identify covered benefits, exclusions, and cost-sharing but does not approve a specific service. Prior authorization represents a formal approval granted by an insurance payer before a service, diagnostic test, procedure, or prescription is provided. Predetermination is a separate written inquiry submitted to obtain an insurer's advance assessment of coverage and anticipated payment for a planned service, though it does not guarantee final payment.

Prior authorization is frequently mandated for costly interventions, including elective surgeries, specialized brand-name pharmaceuticals, and expensive diagnostic imaging such as magnetic resonance imaging (MRI) and computed tomography (CT) scans. When initiating this process under provider supervision, the medical assistant gathers the provider's written orders and supporting clinical documentation. The medical assistant must use diagnosis and procedure codes that have been confirmed by the provider or clinic coding staff. Requests are submitted directly to payers using payer web portals, secure electronic health record tools, or structured telephone calls. The medical assistant should promptly alert the provider to an urgent clinical concern; if the provider determines that care can safely await payer review, staff may request expedited authorization when available, but emergency care must not be delayed for authorization.

A medically necessary service generally must meet applicable coverage criteria and be reasonable and necessary to diagnose or treat illness or injury or improve functioning; some preventive services are covered under separate rules. On insurance claims, linking the provider-documented ICD-10-CM diagnosis code to the corresponding CPT or HCPCS service code supports medical necessity, but linking alone does not establish it. When applicable, National Coverage Determinations (NCDs) and Local Coverage Determinations (LCDs) specify Medicare coverage and medical-necessity criteria; statutes, regulations, and other Medicare guidance may also govern coverage. Medical assistants must remember that obtaining prior authorization confirms that the payer reviewed the proposed service against its specific clinical criteria based on the submitted materials, but it does not guarantee final claim payment. If a required prior authorization is missed before non-emergency care is delivered, the payer will typically deny the claim entirely. Therefore, the medical assistant must carefully record the authorization number in the patient's record, include it on the claim when required by the payer, and track authorization expiration dates to ensure care occurs within the approved timeframe.