If you are seeking a psychological exam on a chronic pain patient, explain to the patient and his/her primary provider that you need to determine if there are any psychological factors that complicate the patient_s coping with pain.
If you are seeking a psychological exam to determine problems with patient motivation and compliance, you explain to the patient that you need to determine if there are issues that are complicating the rehabilitation process.
If the concern is for occult depression (problems with mood that are being displayed as irritability and/or withdrawal), then you let the patient and authorized treating physician(s) know that you feel that there may be complications to the injury that no one has diagnosed and addressed.
If you feel that there is some form of conscious symptom amplification occurring, you tell the patient that you need a fuller understanding of their needs and goals.
Finally, if you question whether surgery will help (or has helped) the patient, you let all involved know that you are concerned for the preparedness of the patient for surgery and its aftermath.