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Medical Necessity

Definitions of Medical Necessity and Investigational Services

Health Net's National Medical Advisory Council (MAC) has provided clarification of terms used in its medical policies for medical necessity, investigational or experimental, and not medically necessary and not investigational. This clarification should enable participating physician groups (PPGs) to more quickly determine whether a service is considered investigational and, therefore, submit the request for a proposed service timely to Health Net for utilization management (UM) review and determination based on the terms of the provider's contract.

Medical necessity for covered services is determined by the applicable statutory Medicare or Medi-Cal standard for the service involved. In the event such service is covered by both Medicare and Medi-Cal, the more generous of those two standards are applied.

  • Medicare standard - those services that are reasonable and necessary for the diagnosis or treatment of illness or injury to improve the functioning of a malformed body member, or otherwise medically necessary under 42 CFR §1395y
  • Medi-Cal standard - those services that are reasonable and necessary to protect life, prevent significant illness or significant disability, or to alleviate severe pain through the diagnosis or treatment of disease, illness or injury as stated under Welfare and Institutions Code (WIC), Section 14059.5

Medically necessary services, or medical necessity, is defined as health care services that a physician, exercising prudent clinical judgment, would provide to a member for the purpose of preventing, evaluating, diagnosing, or treating an illness, injury, disease, or its symptoms, and that are:

  • In accordance with generally accepted standards of medical practice
  • Clinically appropriate, in terms of type, frequency, extent, site, duration, and are considered effective for the member's illness, injury or disease
  • Not primarily for the convenience of the member, physician or other health care provider and not more costly than an alternative service or sequence of services at least as likely to produce equivalent therapeutic or diagnostic results as to the diagnosis or treatment of that member's illness, injury or disease

For these purposes, "generally accepted standards of medical practice" means standards that are based on credible scientific evidence published in peer-reviewed medical literature generally recognized by the relevant medical community, physician specialty society recommendations, the views of physicians practicing in relevant clinical areas and any other relevant factors.

Title 22: Medical Necessity - Definition

Medically necessary services, or medical necessity, includes all covered services that are reasonable and necessary to protect life, to prevent illness or disability, alleviate severe pain through the diagnosis or treatment of disease, illness or injury, achieve age-appropriate growth and development, and attain, maintain or regain functional capacity.

When determining the medical necessity of covered services for Medi-Cal beneficiaries under the age of 21, medical necessity is expanded to include the standards under 42USC Section 1396d(4) and W & I Code Section 14132 (V).

The Centers for Medicare and Medicaid Services (CMS) defines medical necessity and medically necessary services as services or supplies that: are proper and needed for the diagnosis or treatment of medical conditions, are provided for the diagnosis, direct care, and treatment of the member's medical condition, meet the standards of good medical practice in the local area; and are not mainly for the convenience of the patient or health care provider.

Last Updated: 04/29/2019