Current Procedural Terminology (CPT) codes provide a standardized language for medical billing in the United States. Maintained by the American Medical Association, these five-digit codes translate medical services into uniform numbers for insurance claims processing. CPT 90791 is the specific code assigned to a psychiatric diagnostic evaluation without medical services. This code identifies the comprehensive initial assessment necessary to understand a patient’s mental health condition, establish a diagnosis, and create a plan for care.
CPT 90791 Defined: The Initial Psychiatric Assessment
CPT 90791 identifies the integrated biopsychosocial assessment of a patient’s mental health status. This information-gathering session establishes a preliminary diagnosis and formulates a treatment plan, rather than providing ongoing therapy. The assessment sets the baseline for all subsequent mental health care, ensuring treatment interventions match the patient’s specific needs.
The code does not include medical services, such as prescribing medication or ordering laboratory tests. When medical services are included in the initial evaluation, a different code, 90792, is used by medically licensed professionals like psychiatrists or psychiatric nurse practitioners. A broad range of licensed professionals can perform and bill for CPT 90791, including Licensed Clinical Social Workers, Licensed Professional Counselors, Licensed Marriage and Family Therapists, and Clinical Psychologists.
The intake assessment requires synthesizing information from multiple dimensions of a person’s life. Although the code is not associated with a specific time component, a thorough evaluation often takes 45 to 60 minutes or more. The resulting documentation acts as the clinical record that justifies the medical necessity of all future treatment services.
Key Elements of the Diagnostic Evaluation
The clinical work required to bill CPT 90791 requires comprehensive history taking that explores the patient’s past and present circumstances. This includes a review of the patient’s psychiatric history, current symptoms, social and family history, and any relevant substance use history.
A detailed mental status examination (MSE) is a mandatory component of the evaluation, assessing the patient’s current cognitive, emotional, and behavioral functioning. During the MSE, the clinician observes and documents the patient’s appearance, speech, mood, thought process, and insight. Gathering this information allows the provider to formulate a differential diagnosis.
The evaluation must also include a risk assessment to identify any immediate threats to the patient’s safety or the safety of others. This involves evaluating suicidal ideation, self-harm risks, and potential for violence, along with identifying protective factors and support systems. The provider selects the most appropriate diagnosis using the standard diagnostic manual and develops initial treatment recommendations based on the comprehensive assessment.
Application and Usage Guidelines
CPT 90791 is typically limited to the beginning of care, representing the initial assessment for a new patient or a new episode of care. This code is generally billed only once per episode of care, or when a new, unrelated condition arises. Some insurance plans may allow it once per year, but strict limits prevent frequent use.
This code is distinct from psychotherapy codes, such as the 9083x series, which are used for ongoing treatment sessions. While CPT 90791 is an assessment, the psychotherapy codes represent the active treatment and intervention phases of care. Providers must not bill 90791 on the same day as a psychotherapy service for the same patient, as the two services have different clinical purposes.
Insurance coverage for the psychiatric diagnostic evaluation is common, but payers strictly monitor the frequency of its use. Documentation is paramount to justify the use of this code and secure reimbursement. The clinical record must clearly support the medical necessity of the evaluation by including the patient’s presenting problem, the findings of the mental status exam, and the initial treatment plan.