Medical Necessity Guidelines Medically Necessary Services
Defines how Mass General Brigham Health Plan determines medical necessity for covered services across plan types and what evidence and criteria are used; applies to providers requesting coverage for plan members.
Replaced link to the Experimental and Investigational medical policy with the hierarchy of evidence sufficient to support treatment.
Added new criterion to ACO, Commercial, and Qualified Health Plans section.
Updated Determination of medical necessity: Medicare Advantage section and added Hierarchy of criteria section.
Coverage and Medical Necessity Criteria
General medical necessity criteria
Covered when ALL of the following are met:
From policy evidentiary criteria
Hierarchy of criteria
Plan-specific determination order (priority of criteria sources):
Policy describes tiered precedence of criteria sources
Medical director determination
When no specific criteria exist:
Applies across plan types
Mass General Brigham Health Plan does not provide benefits or reimbursement for services that it considers experimental or investigational. Coverage is limited to services listed in a plan's Covered Services List and those that meet the Plan's medical necessity requirements. For Medicare Advantage members, the Plan specifically does not cover services listed in section 1862 of the Social Security Act (42 U.S.C. 1395y), which describes exclusions from Medicare coverage and Medicare as a secondary payer.
When the available high-quality evidence is insufficient to demonstrate that a treatment meets the policy's evidentiary requirements, the treatment is not covered for that clinical situation. The evidentiary requirements include demonstration that benefits outweigh harms, that outcomes are superior or comparable to established alternatives, that improvements are achievable outside investigational settings, and that the treatment is clinically appropriate, among other criteria. If these criteria cannot be satisfied by the evidence, coverage is denied.
Provider Requirements, Prior Authorization, and Review
Prior Authorization Review Process
Prior authorization review process — Services on the medical benefit are determined using InterQual criteria (Change Healthcare), customized InterQual criteria, and Mass General Brigham Health Plan medical policies. For drugs on the medical benefit of commercial plans and qualified health plans, the Plan utilizes Mass General Brigham Health Plan medical policies and Mass General Brigham Health Plan medical specialty drug policies to determine medical necessity. For ACO members, medical necessity criteria are not more restrictive than MassHealth guidelines and MassHealth criteria are used for drugs on the MassHealth Drug List. For Medicare Advantage members, CMS guidance (NCDs, LCDs, LCAs, Medicare manuals) is used; when CMS guidance is not available, Mass General Brigham Health Plan medical policies, InterQual, and other vendor policies are used. If a requested service requires a medical necessity determination but no applicable criteria exist in InterQual, Mass General Brigham Health Plan medical policies, MassHealth guidance (if applicable), or CMS guidance (if applicable), the request is escalated to a medical director. The medical director may also utilize external specialists to review requests. In these circumstances the medical director and/or external specialist will determine whether available scientific evidence demonstrates the service is safe and effective for the particular clinical situation using the Plan's hierarchy of reliable evidence.
- Commercial & Qualified Health Plans: InterQual, customized InterQual, and MGB Health Plan medical policies determine medical necessity.
- Mass General Brigham ACO: InterQual + MGB policies; MassHealth criteria apply for drugs on MassHealth Drug List.
- Medicare Advantage: CMS guidance (NCDs, LCDs, LCAs, Medicare manuals) used first; fallback to MGB policies/InterQual when CMS guidance absent.
- If no criteria exist in applicable sources (InterQual, MGB policies, MassHealth, CMS), escalate to medical director review — external specialists may be consulted.
Denial Triggers
Denial triggers — Requests will be denied when the available high-quality evidence is insufficient to demonstrate that the service meets the Plan's medical necessity requirements. The medical director and/or external specialist considers only reliable evidence published in credible, peer-reviewed English-language journals and applies the Plan's hierarchy of reliable evidence (systematic reviews/meta-analyses, randomized controlled trials, large non-randomized trials, well-designed observational studies with concurrent comparison groups, observational studies with historical comparisons, case series, expert opinion). The evidence must show that all of the following are met: benefits outweigh harms; outcomes are superior or comparable to established alternatives; improvement is likely to be realized outside investigational settings; cost-effectiveness compared with likely alternatives; clinically appropriate in type, frequency, extent, site, and duration; provided at the least intensive/least restrictive level of care that is at least as safe and effective as alternatives; provided in accordance with generally accepted standards of medical practice; and not primarily for convenience. If evidence is insufficient to draw these conclusions for the specific clinical situation, the treatment is not covered.
- Denial when high-quality evidence is insufficient to meet medical necessity criteria.
- Evidence assessed using Plan hierarchy (systematic reviews, RCTs, non-randomized trials, observational studies, case series, expert opinion).
- All required criteria (benefit > harm; comparable/superior to alternatives; realizable outside investigational settings; cost-effectiveness; clinical appropriateness; least intensive/restrictive level; aligns with accepted practice; not for convenience) must be met.
When Medical Director Review Is Required
When medical director review is required — A medical director review is required when no specific medical necessity criteria exist in InterQual, Mass General Brigham Health Plan medical policies, MassHealth guidance (for ACO/MassHealth-covered services), or CMS guidance (for Medicare Advantage). The medical director may consult external specialists. During review, the medical director and/or specialist evaluates whether reliable scientific evidence demonstrates the treatment is safe and effective for the member's specific clinical situation, applying the Plan's hierarchy of evidence and the full set of medical necessity criteria. For Medicare Advantage, the medical director follows the Medicare Program Integrity Manual guidance when applying these determinations.
- Triggers for escalation: absence of criteria in InterQual, MGB medical policies, MassHealth (if applicable), or CMS (if applicable).
- Medical director may consult external specialists.
- Review applies Plan hierarchy of reliable evidence and the full medical necessity criteria list.
- For Medicare Advantage, determinations reference Medicare Program Integrity Manual guidance.
Definitions and Evidence Hierarchy
Background and Scope
Mass General Brigham Health Plan determines medical necessity across plan types using a prioritized set of sources. For Commercial and Qualified Health Plans the Plan applies InterQual criteria (including customized InterQual content) and Mass General Brigham Health Plan medical policies; for Medicare Advantage members the Plan follows CMS guidance (NCDs, LCDs, LCAs, Medicare manuals) first and then uses Plan policies and InterQual when CMS guidance is absent. If no applicable criteria exist in the top-priority sources for a given plan type, a medical director — who may consult external specialists — will review the request and evaluate published evidence using the policy's hierarchy of reliable evidence to determine whether the treatment is safe and effective for the specific clinical situation.
Revision History and Policy Changes
Material updates to this policy were made with an effective date of January 1, 2025. Key edits include: replacement of a link to the Experimental and Investigational medical policy with an explicit hierarchy of evidence sufficient to support treatment decisions; addition of a new criterion for ACO, Commercial, and Qualified Health Plans; and clarified use of CMS guidance and the criteria hierarchy when determining Medicare Advantage medical necessity. Prior ad hoc and annual reviews in 2025–2026 further refined the Determination of Medical Necessity and Hierarchy of Criteria sections.
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