Coverage of Conditions and Treatments (Coverage Decisions)

Use this lookup tool to determine coverage decisions, or if prior authorization is needed for the treatment or condition. Note: For Self-insured employer claims, you must contact the employer or their claims administrator.

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Archived Coverage Decisions.

See Treatment Guidelines and Resources for additional information.

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The department or self-insurer does cover use of electrodiagnostic testing including nerve conduction studies and needle electromyography only when:

  • Proper and necessary and
  • Testing meets the requirements described in this policy.


Electrodiagnostic testing, including nerve conduction studies (NCS) and needle electromyography (EMG), is used to identify or diagnose injury or diseases of or affecting the peripheral nervous system and skeletal muscles. NCS testing typically involves use of surface electrodes which stimulate nerves through small electric shocks and record the information back from the nerves (eg, conduction velocity, wave forms, and amplitude). This information may provide valuable diagnostic information necessary to develop or inform a treatment plan.

Needle electromyography (EMG) is an invasive procedure and is performed in a similar manner to NCS, except that stimulation and/or recording occur through fine needle electrodes inserted into or near muscle and nerve tissue.

NCS and EMG are traditionally performed by specialist physicians trained in neurophysiology programs such as physical medicine and rehabilitation (PMR) or neurology. NCS Testing may also be performed by trained technicians working under the direct supervision of physicians trained in neurophysiology. In the majority of situations, the needle EMG and the NCS examinations should be conducted and interpreted at the same time.

This policy adopts, in large part, the recommendations for the proper performance of NCS and EMG from the American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM), and refers to Center for Medicare and Medicaid (CMS) payment policy. The AANEM has developed coverage policy and reimbursement recommendations for insurers. The AANEM recommendations are endorsed by the American Academy of Neurology and the American Academy of Physical Medicine & Rehabilitation.

Test requirements

Requirements for appropriate electrodiagnostic testing

  • EMG and NCS should be performed by or under the direct, in office, supervision of a neurologist or physical medicine and rehabilitation specialist (physiatrist). Direct supervision is defined by Centers for Medicare and Medicaid Services (CMS) to mean the physician is present in the office suite when the test is performed.The physician interpreting EMG and NCS results should be formally trained in neurology, or physical medicine and rehabilitation.
    • Exception: Per Washington State law, physical therapists who meet the requirements of Department of Health (DOH) rule (WAC 246-915-370) may perform EMG and NCS upon referral by an authorized healthcare practitioner (RCW 18.74.010(7)). The authorized practitioner must be the Attending Provider on the injured worker's claim, a consultant, or a provider authorized by the insurer to provide concurrent care on the claim.
  • Interpretation and diagnosis of EMG and NCS results requires face-to-face contact with the patient.
  • Diagnosis, based on results of EMG or NCS for the purposes of Washington State Workers’ Compensation claims, must be made by the neurologist or physiatrist, or by the Attending Provider, a consultant, or a provider authorized by the insurer to provide concurrent care on the claim.
  • Technicians may perform NCS under the direct, in office, supervision of a neurologist or physiatrist.
  • EMG and NCS testing for suspected carpal tunnel syndrome is addressed in the department's Medical Treatment Guidelines for Carpal Tunnel Syndrome.

Non-covered electrodiagnostic testing services

  1. Testing which is not Proper and Necessary per WAC 296-20-01002.
    In general, repetitive testing is not considered Proper and Necessary except:
    i.     To document ongoing nerve injury, for example, following surgery.
    ii.    If required for provision of an impairment rating.
    iii.   To document significant changes in clinical condition.
  2. Testing by mobile diagnostic labs, in which the specialist physician is not present to examine and test the patient.
  3. Testing with non-covered devices including portable, automated and ‘virtual’ devices not demonstrated equivalent to traditional lab-based equipment (eg, NC-stat®, Brevio).
  4. Testing determined to be outside of AANEM recommended guidelines without proper documentation supporting that it is proper and necessary. Get complete AANEM recommendations.

Billing information

For billing information, please refer to the Payment Policies.