C621 – Complex Medical Specific Re-Assessment
OHIP Surgical Procedures Code — Clinical Immunology (62) · Schedule of Benefits
A complex medical specific re-assessment is a service rendered to a non-emergency hospital in-patient by a Clinical Immunology specialist. The service is for the re-assessment of a patient because of the complexity, obscurity, or seriousness of the patient's condition. It includes all the requirements of a medical specific re-assessment, which involves a full, relevant history and physical examination of one or more systems. A key requirement for payment is that the physician must report their findings, opinions, or recommendations in writing to the patient's primary care physician. If this report is not provided, the amount payable for the service will be adjusted to a lesser assessment fee. This service is also subject to the specific elements of all assessments as defined in of the Schedule.
When to Use
- Use C621 for a complex, obscure, or serious immunological re-assessment of an existing hospital inpatient that requires a full history and physical examination of one or more systems.
- Use this code when the clinical complexity necessitates a formal written report to the primary care physician to justify the higher complexity fee over a standard C622 medical specific re-assessment.
Common Pitfalls
- Failure to generate and send a formal written report to the primary care physician will trigger an automatic adjustment to a lower assessment fee upon audit.
- Exceeding the limit of 4 combined medical specific assessments and complex re-assessments per patient per physician per 12-month period will result in automatic payment downgrades.
- Billing C621 for a patient already seen by you for a different assessment on the same day will result in a rejection, as only one assessment is payable per visit.
Billing Tips
- Ensure your documentation explicitly justifies the 'complexity, obscurity, or seriousness' of the condition to support the C621 claim during a post-payment review.
- If the patient is in an ICU or CCU, remember to append the C101 premium to the C621 claim to capture the additional flat fee for intensive care settings.
Effective: June 1, 2025
Consultations and Visits
Clinical Immunology (62)
Assessment
Hospital and Institutional Consultations and Assessments
The physician must report his/her findings, opinions, or recommendations in writing to the patient's primary care physician or the amount payable for the service will be adjusted to a lesser assessment fee.
For Services not listed, refer to Internal Medicine Section.
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