InterQual & MCG Criteria: A Clear Guide for Outpatient Practices

Recent research suggests that nearly all people in Medicare Advantage plans are subject to at least one prior authorization policy, and many of those decisions lean on InterQual or MCG criteria in the background. If you run an outpatient clinic, you feel this every day as delayed starts, stalled schedules, and staff time lost to back and forth with payers.

At the highest level, InterQual and MCG criteria are structured, evidence based rule sets that payers use to judge medical necessity. They sit inside broader utilization management programs, which are designed to confirm that care is appropriate, in the right setting, and aligned with current clinical standards.

For an outpatient therapy or specialty clinic, that abstract description shows up in very concrete ways.

• Access: If requests do not clearly align with the criteria, authorizations take longer, patients wait, and some never start care. When documentation tracks closely with the way criteria are written, decisions arrive faster and fewer patients drop off the schedule.
• Throughput: Every delayed authorization leaves a hole in the day. Multiply that across multiple providers and locations and you start to see a real ceiling on how many visits you can complete. Cleaner submissions that match InterQual or MCG expectations tend to reduce resubmits and peer-to-peer calls, which gives you more usable appointment slots.
• Staff workload: Administrators and clinical staff are already stretched. Each avoidable denial adds calls, portal messages, and faxes to their task list. When the intake process is more systematic, especially if you use tools such as an AI powered unified inbox that collects all payer and patient messages in one place, the same team can handle more volume without burning out.

Platforms like Solum Health emphasize this operational angle, positioning themselves as a unified inbox and AI intake automation layer for outpatient facilities and specialty practices, integrated with EHR and practice management systems and designed to deliver measurable time savings. You do not need to change payers to feel a difference, but you do need to understand the logic that guides their reviewers.

How InterQual and MCG criteria work in utilization management

Both InterQual and MCG live inside the broader framework that many payers call utilization management, which includes prior authorization before care, concurrent review during care, and retrospective review after the fact. These programs depend on clinical criteria to anchor decisions in a consistent standard.

InterQual criteria tend to be highly granular. They often specify required findings, acceptable diagnostic workups, and particular thresholds for severity or risk. When a reviewer looks at a prior authorization request, they compare your documentation with those items.

MCG criteria lean more on care pathways and expected recovery timelines. They set out a typical course of treatment, the time frames that match most patients, and the situations that justify more intensive or extended care.

In practice, both systems are trying to answer the same question. Does this patient, at this moment, meet an accepted definition of medical necessity, meaning that the requested service is likely to help and is consistent with current standards of care?

That definition tracks closely with how national bodies describe medically necessary services, as care that can reasonably be expected to produce the intended result and that meets accepted professional standards.

The five key steps behind most medical necessity reviews

From the clinic side, you may only see an electronic form and a fax number. Behind the scenes, most prior authorization reviews that use InterQual or MCG follow a similar internal sequence.

1. Clinical assessment: Your clinicians document symptoms, functional limits, prior treatments, and goals. Thin or generic notes force reviewers to infer severity, which rarely works in your favor.
2. Matching to the correct guideline: Utilization staff on the payer side select the most relevant InterQual or MCG guideline. If your request is vague, they may choose a more conservative or less intensive guideline than you expected.
3. Comparing your notes with the criteria: Reviewers check whether what you documented lines up with required or strongly supported elements in the criteria. That might include specific test results, standardized scale scores, or clearly described risks.
4. Issuing a decision or requesting more information: If the match is clear, the request is approved. If important elements are missing, the case is pended and someone on your team gets an additional information request, which adds delay and work.
5. Appeal, reconsideration, or continuation: When you disagree with a denial, the same criteria are often used again in appeal. If your team learns how to structure information around those criteria, both initial and appeal submissions improve.

None of this replaces clinical judgment. It does mean that your documentation either makes it easy or very difficult for the reviewer to say yes.

Practical steps to adopt criteria aware workflows

You do not need direct access to InterQual or MCG to make progress. You can start with process changes inside your own walls.

• Build a standard intake packet for any service that routinely requires prior authorization. Collect the same core elements every time, for example severity measures, duration of symptoms, clear functional impact, and previous conservative treatment. Route that packet into a single system, such as a unified inbox, so staff are not hunting across email, portal messages, and scanned forms.
• Train one or two staff members to act as internal translators. They will not see the criteria books, but they will start to notice which details payers always ask for. Capture those patterns in simple checklists or templates. Keep those templates in the same place where you store your AI intake automation workflows or EHR macros so they are easy to reuse.
• Tie communication and intake together. Many clinics still treat benefits checks, intake forms, and referral faxes as separate chores. If you rely on an AI powered unified inbox and intake automation platform, or any similar architecture, you can bring these steps into one queue, reduce status chasing, and feed better information into each request.
• Use external guidance to educate your team. Resources on utilization management explain how criteria based programs are supposed to work, including the difference between benefit denials and medical necessity denials. Sharing that context helps staff treat each request as part of a larger system, not just a form to fill out.

Finally, track your own numbers. Clinics that measure their denial rates and rework time around prior authorization can see whether changes to documentation and workflow are paying off.

Common pitfalls to avoid

• Assuming that volume equals strength: Five pages of notes that never state functional impact will underperform a concise note that clearly describes how the condition limits daily activity.
• Letting intake live in silos: If your front desk, clinical team, and billing staff all collect different fragments of the story, no one has the full picture when it is time to submit. Linking those steps through a tool such as a centralized intake and messaging workflow keeps the data in one place.
• Ignoring feedback from denials: Denial letters often hint at which criteria elements were not met. If you treat those letters as pure frustration, you lose that signal. If you mine them for patterns, you can tighten your documentation playbook.
• Treating every payer as completely different: Yes, policies vary. Still, most criteria sets cluster around the same themes, symptom severity, risk, prior treatment, expected benefit. That means improvements in how you capture those basics will tend to pay off across plans.

Brief FAQ

What is the main difference between InterQual and MCG criteria?
InterQual tends to organize guidance in very detailed, condition specific items, while MCG relies more on care pathways and expected timelines. Both are used to assess whether a requested service meets accepted standards of medical necessity.

Do all health plans use these criteria?
Many large plans use one of these tools or a similar criteria set, often combined with internal medical policies. From your perspective, the process feels similar, a structured review that checks your request against written standards.

Are the criteria public?
No, they are proprietary products that payers and some provider organizations license. What you can usually see are the effects, in the form of policy summaries and the reasoning sections in authorization letters.

How can outpatient clinics improve their authorization documentation?
Focus on four things, clear description of symptoms, specific functional impact, prior or concurrent treatment, and the reason you are asking for this service, intensity, and duration now. Aligning those elements with typical criteria themes improves approval odds.

Do InterQual and MCG determine how many visits a patient can have?
The criteria do not set hard visit limits. They inform whether a given service is medically necessary at a point in time. Actual caps come from plan design, although criteria based reviews often determine whether extended care will be approved when you reach those thresholds.

A short action plan for this quarter

If you want to move from reacting to denials to shaping them, you can treat this as a three part project.

First, map your highest friction services, the ones that generate the most prior authorization work. Second, redesign intake and documentation for those services so that core elements of severity, function, prior treatment, and rationale are always present, ideally captured through a shared system such as an integrated unified inbox and AI intake automation workflow that connects cleanly with your EHR and practice management systems. Third, track denial rates and rework time over several months, and refine your templates based on real responses from payers.

You cannot rewrite InterQual or MCG, and you cannot erase prior authorization overnight. You can, however, make that world more predictable for your staff and your patients, and that is the kind of progress that compounds over time.