The California Labor Code designates the use of ACOEM Guidelines, which are presumptively correct. ACOEM guidelines address chronic pain in Chapter 6, and advocate the use of interdisciplinary care in some cases.

Requesting an Initial Assessment

"Physicians should consider referral for further evaluation and perhaps cooperative treatment if:

Specific clinical findings suggest undetected clinical pathology.
Pain distribution is non anatomic or described in a bizarre or atypical manner. Common examples include glove or stocking like pain or paresthesias, shock like pain, pain that radiates up and down the neck and back, burning pain, and pain that is present constantly regardless of position, medication use or physical treatments.
Medication use does not decrease as expected, or increases.
Appropriate active physical therapy does not appear to be improving function as expected.
Complaints of pain or dysfunction start to involve other areas of the body, including instances in which the patient:

Ceases to discuss returning to work in a specific time frame but rather in relation to a cure.
Fails to benefit from any, or all, rational therapeutic interventions.
Experiences increased pain, or at the very least, pain does not decrease, over time.
Is unwilling to discuss his or her family situation or expresses comfort with role reversal at home.
States the illness or injury as caused all of his or her problems.
Directs excessive anger at the employer or co-workers, the physician, or an insurer and/or demonstrates an attitude of revenge or wanting to prove that he or she is sick.
Is less interested in-home therapy program or even in recovery of function.

Judicious referral also is warranted to collaborate the absence of physical pathology, which can be the basis of assurances to the patient that increased participation in usual activities will not be detrimental to his or her overall physical status".

(Chapter 6, Pain, Suffering, and the Restoration of Function, pg. 112 ACOEM 2nd ED).