Which level of service code typically indicates a more complex patient evaluation?

The choice indicating established patient, high complexity, is the correct response because it aligns with the coding guidelines that categorize patient evaluations based on their complexity and the level of medical decision-making involved.

In the context of evaluation and management (E/M) services, established patient codes indicate a follow-up evaluation for patients who are already known to the provider. A high complexity level suggests that the patient evaluation involves multiple, significant problems, particularly those requiring extensive examination and significant medical decision-making, such as the management of chronic conditions or the assessment of new symptoms that could suggest serious diagnoses.

This contrasts with the other options. For instance, established patient codes that denote low complexity would generally reflect simpler evaluations, while new patient codes suggest a comprehensive assessment of someone who has not previously been seen by the provider. However, they do not necessarily carry the same weight as established high complexity evaluations, where the provider already has a substantial background on the patient's health status. Therefore, a code for established patients at a higher complexity level clearly denotes a more involved assessment role and the need for substantial decision-making, validating its designation as indicative of a complex evaluation.