90791 — Psychiatric Diagnostic Evaluation
An integrated biopsychosocial assessment including history, mental status exam, and diagnosis. This is a non-medical diagnostic evaluation performed without medical services (no E/M component). Used for initial intake assessments by therapists, counselors, psychologists, and social workers.
Time Requirements
Typically 45-90 minutes. No strict time floor, but documentation must support the complexity billed.
Modifiers
| Code | Description |
|---|---|
| 95 | Synchronous telemedicine service rendered via real-time audio/video. |
| GT | Via interactive audio and video telecommunications systems (legacy; 95 is preferred). |
When to Use
- Initial intake evaluation for a new client
- Comprehensive re-evaluation when diagnosis is being reconsidered
- Court-ordered or forensic psychiatric evaluation
- When establishing a new treatment plan based on a full diagnostic workup
When Not to Use
- Routine follow-up therapy sessions — use 90834 or 90837 instead
- When only providing medication management — use E/M codes
- Brief screenings or questionnaire administration alone
- When the evaluation is primarily medical in nature — use 90792
Common Denial Reasons
- Billed more than once per provider per client without documentation of medical necessity for re-evaluation
- Documentation does not support a full diagnostic evaluation (missing history, MSE, or diagnostic formulation)
- Billed on the same date as a therapy code without modifier 25 or adequate documentation
- Missing or invalid diagnosis code on the claim
Payer Notes
Most payers allow one 90791 per client per provider. Some Medicaid programs allow a second if there is a significant change in clinical presentation. Pre-authorization is rarely required but check payer-specific policies.
Frequently Asked Questions
WellNotes generates notes aligned with CPT 90791 billing requirements
Spend less time on documentation and more time with clients. Notes are structured to support clean claims.
Stop spending evenings on documentation
WellNotes generates complete clinical notes in 2 minutes. Try it free for 7 days.
7-day free trial · Cancel anytime · Secure & private