Which of the following is considered an unallowed referral?

Offering compensation for referred evaluations is indeed considered an unallowed referral because it creates a conflict of interest and can distort the integrity of the referral process. In medical practice, ethical standards dictate that referrals should be based solely on the needs of the patient and the qualifications of the specialist, rather than financial incentives. Such compensation could lead to inappropriate referrals, overutilization of services, or exploitation of patients, undermining their best interests.

In contrast, referring patients to a local specialist with no financial interest is typically permissible, as it aligns with helping the patient receive the care they need without any ulterior motives. Referring based on patient preference is also acceptable as it respects the patient's autonomy and choice regarding their healthcare providers. Lastly, internal referrals within the same clinic can be a standard practice, especially if it facilitates comprehensive care while maintaining a consistent standard in the quality of evaluation and treatment.